78SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
Performance/Functional Speci? cations TECHNICAL NOTES (continued)
Typical at TA = +25?C & VIN = 12V, unless otherwise noted
3. Input-Output Isolation: 78SR regulators? internal input and output
circuits share a common connection (GND, pin 2), there is no
Input/Output electrical isolation between their INPUT (pin 1) and OUTPUT (pin 3)
terminals.
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
Output Voltage 3.3Vdc 5.0Vdc 5.25Vdc
4. Overvoltage Protection: 78SR switching regulators do not provide
Rated Output Current 2.0A 2.0A 2.0A
input or output overvoltage protection. In the extremely rare situation
Output Voltage Accuracy ?2% ?2% ?2%
where a catastrophic failure occurs, the output voltage may rise to
Input Voltage Range 8.0-32Vdc 8.0-32Vdc 8.0-32Vdc
excessively high levels. If the load circuit must be protected against
Line Regulation (100% load) ?0.35% ?0.35% ?0.35%
all possible overvoltage situations, voltage-limiting circuitry must be
Load Regulation (0-100% load) ?0.2% ?0.2% ?0.2%
provided externally.
Quiescent Current (mAdc) 25 typ., 30 max 20 typ., 35max 20 typ., 35max
5. Soldering & Handling Precautions: All units are designed to be
Input Current vs. Input Voltage See Ef? ciency Curves
hand soldered to pc-boards, using lead-free no-clean solders
Ef? ciency See Ef? ciency Curves
(+260?C, 5 seconds max.). See the Mechanical Speci? cations sec-
Transient Response See Performance Curves
tion for pin 1 orientation and recommended pc-board hole dimen-
Input & Output Noise See Performance Curves
sions.
Continuous
Output Short Circuit Protection ?
78SR series regulators have limited built-in ESD protection; there-
Input/Output Isolation None
fore they should always be treated as ESD susceptible devices.
Overvoltage Protection None
6. Horizontal-Pin Models (78SRH): 78SRH switching regulators are
Undervoltage Protection None
pin-compatible replacements for TO-220 style LM78xx linear regula-
Environmental
tors which are installed with their metal tabs or heat sinks laying ? at
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
on the surface of the pc-board. In replacement applications, 78SRH
Operating Temperature ?40 to +70?C
units must be soldered to the pc-board such that the insulating body
Storage Temperature ?40 to +85?C
of diode D1 lies ? at and in contact with the pc-board?s surface.
Free Air Convection
Cooling ?
Humidity (Non-condensing) 0 to 85%
Physical
Mechanical See Mechanical Speci? cations
Package Open-frame SIP
Pins 0.025" (0.64mm) square, tin-plated bronze
Weight 0.15 ounces (4.2g)
Pin Soldering +260?C for 5 seconds
Absolute Maximum Ratings ?
Input Voltage: +36Vdc
Operating Temperature +85?C
Output Current 3.0 Amps
? 78SR Series regulators can withstand a continuous short-circuit across their output
terminals. However, extended short-circuit operation will decrease the unit?s long-term
reliability.
? These are stress ratings only; Exposure of devices to any of these conditions may ad-
versely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Speci? cations Table is not implied.
? See derating chart for more information.
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 2 of 678SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
Performance/Functional Speci? cations TECHNICAL NOTES (continued)
Typical at TA = +25?C & VIN = 12V, unless otherwise noted
3. Input-Output Isolation: 78SR regulators? internal input and output
circuits share a common connection (GND, pin 2), there is no
Input/Output electrical isolation between their INPUT (pin 1) and OUTPUT (pin 3)
terminals.
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
Output Voltage 3.3Vdc 5.0Vdc 5.25Vdc
4. Overvoltage Protection: 78SR switching regulators do not provide
Rated Output Current 2.0A 2.0A 2.0A
input or output overvoltage protection. In the extremely rare situation
Output Voltage Accuracy ?2% ?2% ?2%
where a catastrophic failure occurs, the output voltage may rise to
Input Voltage Range 8.0-32Vdc 8.0-32Vdc 8.0-32Vdc
excessively high levels. If the load circuit must be protected against
Line Regulation (100% load) ?0.35% ?0.35% ?0.35%
all possible overvoltage situations, voltage-limiting circuitry must be
Load Regulation (0-100% load) ?0.2% ?0.2% ?0.2%
provided externally.
Quiescent Current (mAdc) 25 typ., 30 max 20 typ., 35max 20 typ., 35max
5. Soldering & Handling Precautions: All units are designed to be
Input Current vs. Input Voltage See Ef? ciency Curves
hand soldered to pc-boards, using lead-free no-clean solders
Ef? ciency See Ef? ciency Curves
(+260?C, 5 seconds max.). See the Mechanical Speci? cations sec-
Transient Response See Performance Curves
tion for pin 1 orientation and recommended pc-board hole dimen-
Input & Output Noise See Performance Curves
sions.
Continuous
Output Short Circuit Protection ?
78SR series regulators have limited built-in ESD protection; there-
Input/Output Isolation None
fore they should always be treated as ESD susceptible devices.
Overvoltage Protection None
6. Horizontal-Pin Models (78SRH): 78SRH switching regulators are
Undervoltage Protection None
pin-compatible replacements for TO-220 style LM78xx linear regula-
Environmental
tors which are installed with their metal tabs or heat sinks laying ? at
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
on the surface of the pc-board. In replacement applications, 78SRH
Operating Temperature ?40 to +70?C
units must be soldered to the pc-board such that the insulating body
Storage Temperature ?40 to +85?C
of diode D1 lies ? at and in contact with the pc-board?s surface.
Free Air Convection
Cooling ?
Humidity (Non-condensing) 0 to 85%
Physical
Mechanical See Mechanical Speci? cations
Package Open-frame SIP
Pins 0.025" (0.64mm) square, tin-plated bronze
Weight 0.15 ounces (4.2g)
Pin Soldering +260?C for 5 seconds
Absolute Maximum Ratings ?
Input Voltage: +36Vdc
Operating Temperature +85?C
Output Current 3.0 Amps
? 78SR Series regulators can withstand a continuous short-circuit across their output
terminals. However, extended short-circuit operation will decrease the unit?s long-term
reliability.
? These are stress ratings only; Exposure of devices to any of these conditions may ad-
versely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Speci? cations Table is not implied.
? See derating chart for more information.
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 2 of 678SR 2 Amp Series
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Typical Performance Curves TA = +25?C, VIN as indicated
Ef? ciency, Synchronous Switching Regulators
Noise and Ripple - 10% and 100% Load, 20 MHz Bandwidth
78SR-3.3/2 Vin = 12V, ILOAD = 0.2A 78SR-3.3/2 Vin = 12V, ILOAD = 2.0A 78SR-3.3/2 Vin = 24V, ILOAD = 2.0A
78SR-5/2 Vin = 12V, ILOAD = 0.2A 78SR-5/2 Vin = 12V, ILOAD = 2.0A 78SR-5/2 Vin = 24V, ILOAD = 2.0A
Transient Response - 50% Load Step
78SR-3.3/2 25% to 75% Load Step
78SR-3.3/2 25% to 75% Load Step
78SR-3.3/2 75% to 25% Load Step
Vin = 12V Vin = 24V Vin = 12V
CH1: Vout, 50mV/div.
CH1: Vout, 50mV/div. CH1: Vout, 50mV/div.
CH2: Load Current 1A/div. CH2: Load Current 1A/div. CH2: Load Current 1A/div.
25% 75% 25% 75% 75% 25%
40?sec/div. 40?sec/div. 40?sec/div.
78SR-5/2 25% to 75% Load Step 78SR-5/2 75% to 25% Load Step
78SR-5/2 25% to 75% Load Step
Vin = 12V Vin = 24V Vin = 12V
CH1: Vout, 50mV/div.
CH1: Vout, 50mV/div. CH1: Vout, 50mV/div.
CH2: Load Current 1A/div. CH2: Load Current 1A/div. CH2: Load Current 1A/div.
25% 75% 25% 75% 75% 25%
40?sec/div. 40?sec/div. 40?sec/div.
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 3 of 678SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
Performance/Functional Speci? cations TECHNICAL NOTES (continued)
Typical at TA = +25?C & VIN = 12V, unless otherwise noted
3. Input-Output Isolation: 78SR regulators? internal input and output
circuits share a common connection (GND, pin 2), there is no
Input/Output electrical isolation between their INPUT (pin 1) and OUTPUT (pin 3)
terminals.
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
Output Voltage 3.3Vdc 5.0Vdc 5.25Vdc
4. Overvoltage Protection: 78SR switching regulators do not provide
Rated Output Current 2.0A 2.0A 2.0A
input or output overvoltage protection. In the extremely rare situation
Output Voltage Accuracy ?2% ?2% ?2%
where a catastrophic failure occurs, the output voltage may rise to
Input Voltage Range 8.0-32Vdc 8.0-32Vdc 8.0-32Vdc
excessively high levels. If the load circuit must be protected against
Line Regulation (100% load) ?0.35% ?0.35% ?0.35%
all possible overvoltage situations, voltage-limiting circuitry must be
Load Regulation (0-100% load) ?0.2% ?0.2% ?0.2%
provided externally.
Quiescent Current (mAdc) 25 typ., 30 max 20 typ., 35max 20 typ., 35max
5. Soldering & Handling Precautions: All units are designed to be
Input Current vs. Input Voltage See Ef? ciency Curves
hand soldered to pc-boards, using lead-free no-clean solders
Ef? ciency See Ef? ciency Curves
(+260?C, 5 seconds max.). See the Mechanical Speci? cations sec-
Transient Response See Performance Curves
tion for pin 1 orientation and recommended pc-board hole dimen-
Input & Output Noise See Performance Curves
sions.
Continuous
Output Short Circuit Protection ?
78SR series regulators have limited built-in ESD protection; there-
Input/Output Isolation None
fore they should always be treated as ESD susceptible devices.
Overvoltage Protection None
6. Horizontal-Pin Models (78SRH): 78SRH switching regulators are
Undervoltage Protection None
pin-compatible replacements for TO-220 style LM78xx linear regula-
Environmental
tors which are installed with their metal tabs or heat sinks laying ? at
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
on the surface of the pc-board. In replacement applications, 78SRH
Operating Temperature ?40 to +70?C
units must be soldered to the pc-board such that the insulating body
Storage Temperature ?40 to +85?C
of diode D1 lies ? at and in contact with the pc-board?s surface.
Free Air Convection
Cooling ?
Humidity (Non-condensing) 0 to 85%
Physical
Mechanical See Mechanical Speci? cations
Package Open-frame SIP
Pins 0.025" (0.64mm) square, tin-plated bronze
Weight 0.15 ounces (4.2g)
Pin Soldering +260?C for 5 seconds
Absolute Maximum Ratings ?
Input Voltage: +36Vdc
Operating Temperature +85?C
Output Current 3.0 Amps
? 78SR Series regulators can withstand a continuous short-circuit across their output
terminals. However, extended short-circuit operation will decrease the unit?s long-term
reliability.
? These are stress ratings only; Exposure of devices to any of these conditions may ad-
versely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Speci? cations Table is not implied.
? See derating chart for more information.
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 2 of 678SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
www.murata-ps.com
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
FEATURES Murata?s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down,
switching regulators are ultra high-ef? ciency, modern replacements for LM78xx series
??
Up to 95% ef? ciency? no costly heat sinks or fans
1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for
required
TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the
??
3.3V/2A & 5V/2A models; pin compatible with 1.5A 78xx
lowest installed cost, no messy thermal grease, no mounting hardware and no external
regulators
components are required for full operation.
??
Wide 8? 32Vdc input voltage range A 200KHz switching frequency, combined with a synchronous recti? er buck regulator
topology, provides for ef? ciencies exceeding 95%. 78SR switchers can easily drive 2A loads
??
Two package options:
from 12V or 24Vsupplies?at ambient temperatures up to +70?C?without heat sinks,
3-pin vertical mount SIP
fans, or thermal derating. A thermally ef? cient 3-pin vertical mount SIP occupies less than
Low pro? le, horizontal mount SIP
2 2
0.09in. (58mm ) of pc-board real estate, while a horizontal mount option has an installed
??
No external Input/Output ? lter capacitors required
height of less than 0.290in. (7.4mm).
??
?40 to +70?C full load operation at 24Vin with no 78SR Series 2A switching regulators are lower cost, improved-ef? ciency upgrades for
derating many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher ef? ciency ensures
signi? cantly lower heat generation and provides increased run time in battery-powered
??
Excellent load (?0.25%) and line (?0.35%) regulation
applications, making these regulators ideal for today?s low power ?green? applications.
??
Low-cost upgrade for 78HT2, 78SR1, 78ST1, and
PT5100 switchers
TECHNICAL NOTES
??
Open frame design minimizes self-heating & pc-board
1. Input/Output (I/O) Filtering: As shown in the accompanying noise and ripple graphs,
footprint
78SR Series regulators exhibit excellent low noise performance with no additional I/O
??
Includes output short-circuit protection and thermal
? lter components. However, if additional noise reduction is required, be sure to use low
shutdown
ESR capacitors that are rated for continuous operation (with an additional 20% safety
??
Low noise output for powering sensitive instrumentation
margin) at the highest input voltage and ambient temperatures. Adding external output
capacitors will improve the unit?s load-transient response.
Applications in which 78SR regulators are located more than 24 inches (61cm) from
Ordering Information
the input power supply should include an external 47uF/50V (or greater) aluminum
Output Output Input Package
Part No.
electrolytic capacitor, connected as close as possible to the regulator?s +Vin and GND
Voltage Current Voltage Type
terminals (pins 1 and 2). An external input capacitor is particularly important if the input
78SR-3.3/2-C 3.3Vdc
voltage is applied to the regulator via a mechanical switch or relay. Contact bounce at
78SR-5/2-C 5.0Vdc Vertical
turn-on can produce large inductive current spikes, and these current spikes can gener-
78SR-5.2/2-C 5.25Vdc ate potentially damaging voltage transients at the regulator?s input terminals.
2.0A 8.0-32Vdc
78SRH-3.3/2-C 3.3Vdc
2. Input Fusing: 78SR switching regulators are not internally fused. If fusing their input
and/or output terminals is required, use the data shown in the Ef? ciency Curves as a
78SRH-5/2-C 5.0Vdc Horizontal
guide to select an appropriate slow-blow fuse.
78SRH-5.2/2-C 5.25Vdc
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 1 of 6
New 5.2V
model78SR 2 Amp Series
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Ef? ciency, Synchronous Switching Regulators
Performance/Functional Speci? cations TECHNICAL NOTES (continued)
Typical at TA = +25?C & VIN = 12V, unless otherwise noted
3. Input-Output Isolation: 78SR regulators? internal input and output
circuits share a common connection (GND, pin 2), there is no
Input/Output electrical isolation between their INPUT (pin 1) and OUTPUT (pin 3)
terminals.
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
Output Voltage 3.3Vdc 5.0Vdc 5.25Vdc
4. Overvoltage Protection: 78SR switching regulators do not provide
Rated Output Current 2.0A 2.0A 2.0A
input or output overvoltage protection. In the extremely rare situation
Output Voltage Accuracy ?2% ?2% ?2%
where a catastrophic failure occurs, the output voltage may rise to
Input Voltage Range 8.0-32Vdc 8.0-32Vdc 8.0-32Vdc
excessively high levels. If the load circuit must be protected against
Line Regulation (100% load) ?0.35% ?0.35% ?0.35%
all possible overvoltage situations, voltage-limiting circuitry must be
Load Regulation (0-100% load) ?0.2% ?0.2% ?0.2%
provided externally.
Quiescent Current (mAdc) 25 typ., 30 max 20 typ., 35max 20 typ., 35max
5. Soldering & Handling Precautions: All units are designed to be
Input Current vs. Input Voltage See Ef? ciency Curves
hand soldered to pc-boards, using lead-free no-clean solders
Ef? ciency See Ef? ciency Curves
(+260?C, 5 seconds max.). See the Mechanical Speci? cations sec-
Transient Response See Performance Curves
tion for pin 1 orientation and recommended pc-board hole dimen-
Input & Output Noise See Performance Curves
sions.
Continuous
Output Short Circuit Protection ?
78SR series regulators have limited built-in ESD protection; there-
Input/Output Isolation None
fore they should always be treated as ESD susceptible devices.
Overvoltage Protection None
6. Horizontal-Pin Models (78SRH): 78SRH switching regulators are
Undervoltage Protection None
pin-compatible replacements for TO-220 style LM78xx linear regula-
Environmental
tors which are installed with their metal tabs or heat sinks laying ? at
Models 78SR-3.3/2-C 78SR-5/2-C 78SR-5.2/2-C
on the surface of the pc-board. In replacement applications, 78SRH
Operating Temperature ?40 to +70?C
units must be soldered to the pc-board such that the insulating body
Storage Temperature ?40 to +85?C
of diode D1 lies ? at and in contact with the pc-board?s surface.
Free Air Convection
Cooling ?
Humidity (Non-condensing) 0 to 85%
Physical
Mechanical See Mechanical Speci? cations
Package Open-frame SIP
Pins 0.025" (0.64mm) square, tin-plated bronze
Weight 0.15 ounces (4.2g)
Pin Soldering +260?C for 5 seconds
Absolute Maximum Ratings ?
Input Voltage: +36Vdc
Operating Temperature +85?C
Output Current 3.0 Amps
? 78SR Series regulators can withstand a continuous short-circuit across their output
terminals. However, extended short-circuit operation will decrease the unit?s long-term
reliability.
? These are stress ratings only; Exposure of devices to any of these conditions may ad-
versely affect long-term reliability. Proper operation under conditions other than those
listed in the Performance/Functional Speci? cations Table is not implied.
? See derating chart for more information.
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 2 of 678SR 2 Amp Series
2 Amp, 3.3V, 5.0V, & 5.2V Output, High
Typical Performance Curves TA = +25?C, VIN as indicated
Ef? ciency, Synchronous Switching Regulators
Noise and Ripple - 10% and 100% Load, 20 MHz Bandwidth
78SR-3.3/2 Vin = 12V, ILOAD = 0.2A 78SR-3.3/2 Vin = 12V, ILOAD = 2.0A 78SR-3.3/2 Vin = 24V, ILOAD = 2.0A
78SR-5/2 Vin = 12V, ILOAD = 0.2A 78SR-5/2 Vin = 12V, ILOAD = 2.0A 78SR-5/2 Vin = 24V, ILOAD = 2.0A
Transient Response - 50% Load Step
78SR-3.3/2 25% to 75% Load Step
78SR-3.3/2 25% to 75% Load Step
78SR-3.3/2 75% to 25% Load Step
Vin = 12V Vin = 24V Vin = 12V
CH1: Vout, 50mV/div.
CH1: Vout, 50mV/div. CH1: Vout, 50mV/div.
CH2: Load Current 1A/div. CH2: Load Current 1A/div. CH2: Load Current 1A/div.
25% 75% 25% 75% 75% 25%
40?sec/div. 40?sec/div. 40?sec/div.
78SR-5/2 25% to 75% Load Step 78SR-5/2 75% to 25% Load Step
78SR-5/2 25% to 75% Load Step
Vin = 12V Vin = 24V Vin = 12V
CH1: Vout, 50mV/div.
CH1: Vout, 50mV/div. CH1: Vout, 50mV/div.
CH2: Load Current 1A/div. CH2: Load Current 1A/div. CH2: Load Current 1A/div.
25% 75% 25% 75% 75% 25%
40?sec/div. 40?sec/div. 40?sec/div.
www.murata-ps.com/support
MPM_78SR-2A.C01 Page 3 of 6