78253J Series
MAX253 Compatible Converter SM Transformers
SELECTION GUIDE
Output Max. Output Isolation
Input Voltage Turns
Voltage Current Voltage
Order Code
Ratio
V V mA VDC
78253/35JC 3.3 5.0 100 1500 1:2.27
78253/55JC 5.0 5.0 200 1500 1:1.31
78253/35JVC 3.3 5.0 100 4000 1:2.14
78253/55JVC 5.0 5.0 200 4000 1:1.33
ORDER CODE DETAILS
FEATURES
Order Code Package Type Packaging Type Quantity
J-STD-020D reow
78253/XXJ(V)C 6 Pin SM Tube 50
78253/XXJ(V)C-R 6 Pin SM Tape & Reel 500
RoHS compliant
78253/35JC CHARACTERISTICS
Maxim MAX253 compatible
Parameter Conditions Min. Typ. Max. Units
3.3V and 5V versions
Primary Inductance, L 100kHz, 250mV 0.27 0.36 0.50 mH
P
Secondary Inductance, L 100kHz, 250mV 1.60 2.00 2.40 mH
Isolation to 4kVDC
S
Leakage Inductance, L 100kHz, 250mV 0.32 1.00 H
L
Frequency range to 500kHz
Interwinding Capacitance, C 100kHz, 250mV 24 50 pF
WW
Primary D.C. Resistance, R >0.1VDC 0.5 1.00
Toroidal construction
DC
Volt-time Product, Et Pins 1/2 or 2/3 30 49 Vs
Industry-standard pinout
78253/55JC CHARACTERISTICS
UL 94 V-0 package materials
Parameter Conditions Min. Typ. Max. Units
Low prole
Primary Inductance, L 100kHz, 250mV 0.57 0.83 1.10 mH
P
Secondary Inductance, L 100kHz, 250mV 1.10 1.40 1.70 mH
Industrial temperature range S
Leakage Inductance, L 100kHz, 250mV 0.51 1.00 H
L
Interwinding Capacitance, C 100kHz, 250mV 30 50 pF
WW
DESCRIPTION
Primary D.C. Resistance, R >0.1VDC 0.70 1.50
DC
Volt-time Product, Et Pins 1/2 or 2/3 40 70 Vs
The 78253 series of converter transformers are
specically designed for use with the MAX253
78253/35JVC CHARACTERISTICS
chip set to provide isolated power supplies. The
Parameter Conditions Min. Typ. Max. Units
5V input version can supply 1W and the 3.3V
Primary Inductance, L 100kHz, 20mV 110 142 203 H
P
input version can supply 500mW. A centre tapped
Secondary Inductance, L 100kHz, 20mV 550 710 850 H
S
secondary winding allows for full bridge, half
Leakage Inductance, L 100kHz, 250mV 3.46 5.00 H
L
bridge or voltage doubling.
Interwinding Capacitance, C 100kHz, 250mV 2 8.00 pF
WW
For through hole versions see 78253 series Primary D.C. Resistance, R >0.1VDC 0.30 0.50
DC
datasheet. Volt-time Product, Et Pins 1/2 or 2/3 18 30 Vs
78253/55JVC CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Primary Inductance, L 100kHz, 20mV 170 240 335 H
P
Secondary Inductance, L 100kHz, 20mV 350 444 540 H
S
Leakage Inductance, L 100kHz, 250mV 6.28 8.00 H
L
Interwinding Capacitance, C 100kHz, 250mV 3.4 8.00 pF
WW
Primary D.C. Resistance, R >0.1VDC 0.40 0.60
DC
Volt-time Product, Et Pins 1/2 or 2/3 25 37 Vs
All specications typical at T =25C
A
For full details go to
www.murata-ps.com/rohs
www.murata-ps.com/support Technical enquiries email: mk@murata-ps.com, tel: +44 (0)1908 615232
2018-05-11 KMP_78253JC_A04 Page 1 of 578253J Series
MAX253 Compatible Converter SM Transformers
ABSOLUTE MAXIMUM RATINGS
Operating free air temperature range -40C to 85C
Storage temperature range -50C to 125C
400mA
Peak current I
PK
Isolation voltage 78253/XXJC (ash tested for 1 second) 1500VDC
Isolation voltage 78253/XXJVC (ash tested for 1 second) 4000VDC
PACKAGE SPECIFICATIONS
MECHANICAL DIMENSIONS
0.5
(12.70)
0.375
(9.52) MAX Top View
Primary Secondary
1 6
0.354
2 5
(9.0) MAX
78253/55JC
3 4
XYYWW
0.25
(6.35)
0.012 (0.30)
0.025 (0.63)
0.035
0.008 (0.20)
(0.90) 0.021 (0.53)
0.1
(2.54)
Unless otherwise stated all dimensions in inches (mm) 0.01 (0.25).
All pins on a 0.1 (2.54) pitch and within 0.01 (0.25) of true position.
Package weight 1.0g Typ.
RECOMMENDED FOOTPRINT DETAILS
0.06 (1.60)
0.10 (2.54)
0.04
(1.00)
0.45
(11.50)
Unless otherwise stated all dimensions in inches (mm) 0.01 (0.25).
All pins on a 0.1 (2.54) pitch and within 0.01 (0.25) of true position.
www.murata-ps.com/support Technical enquiries email: mk@murata-ps.com, tel: +44 (0)1908 615232
2018-05-11 KMP_78253JC_A04 Page 2 of 5