MIC24045
2
I C Programmable, 4.5V-19V Input,
5A Step-Down Converter
Features General Description
2
4.5V to 19V Input Voltage Range The MIC24045 is an I C-programmable, high-effi-
ciency, wide input range, 5A synchronous step-down
5A (maximum) Output Current
2 regulator. The MIC24045 is perfectly suited for multiple
I C Programmable Output Voltage:
voltage rail application environments, typically found in
- 0.64V to 5.25V in 5 mV, 10 mV, 30 mV and
computing and telecommunication systems. In the
50 mV steps
MIC24045 various parameters can be programmed via
2
High Efficiency (>95%)
I C, such as output voltage, switching frequency,
2
I C Programmability of:
soft-start slope, margining, current limit values and
start-up delays. The wide switching frequency
- Soft-Start: 0.16, 0.38, 0.76 and 1.5V/ms ramp
adjustment range, valley current-mode control tech-
rates
nique, high-performance error amplifier and external
- Switching Frequency: 310 kHz, 400 kHz,
compensation allow for the best trade-offs between
500 kHz, 570 kHz, 660 kHz, 780 kHz, 1 MHz,
high efficiency and the smallest possible solution size.
1.2 MHz
The MIC24045 supports extensive diagnostics and
- Current Limits for 2A, 3A, 4A and 5A loads
2
status information through I C.
- Output Voltage Margining: -5%, +5%
The MIC24045 pinout is compatible with the MIC24046
- Start-up delays: 0 ms to 10 ms
pin-strapping programmable regulator pinout, such that
1% Output Voltage Accuracy Over Temperature
2
I C-based implementations can be easily converted
(0.64V to 1.95V)
into pin-programmable ones.
Supports Safe Start-Up with Pre-Biased Output
2
The MIC24045 is available in a thermally-efficient,
Extensive Diagnostics through I C Interface
space-saving 20-pin 3mmx3mm FQFN package,
with an operating junction temperature range from
Applications
-40C to +125C.
Servers, Data Storage, Routers and Base
Stations
FPGAs, DSP and Low-Voltage ASIC Power
Typical Application
V
DDA
V
IN
4.5V to 19V
V V A BST
INLDO DDA GND
V
IN
V
OUT
0.64V to 5.25V
LX
P
GND
OUTSNS
V
DDP
COMP
MIC24045
V
DDA
SDA ADR1
2
I C
SCL
Address
V
DDA
Selection
ADR0
PGOOD PG
ENABLE EN
2016 Microchip Technology Inc. DS20005568A-page 1MIC24045
Package Types
MIC24045
3x3FQFN*
(Top View)
20 19 18 16
17
V 15 COMP
1 21 V EP
IN
IN_
14
V A
2
IN GND
22 P EP 13 P
P 3
GND GND_ GND
12
P SDA
4
GND
23 LX_EP
11
SCL
LX 5
67 8 9 10
* Includes Exposed Thermal Pad (EP); see Table 3-1.
Functional Block Diagram
EN V V V BST V
INLDO DDA DDP IN
V _EP
IN
Linear
2 A
High-Side
Regulator
10O Current
Limit
UVLO
UVLO
1.21V
Enable
Reference and
Comparator
HS
DAC
Control Logic/ Gate
LX
REF
DAC
Valley Current Mode Drive
LX_EP
UVLO Thermal
Modulator
VDDA
ThSD,
Shutdown and LS
ThWrn
Warning
ADR0 VOUT<7:0> POR
2
ADR1
Ilim<1:0>
I C
P
GND
Interface
Freq<2:0>
SCL P _EP
GND
and
SS<1:0>
SDA I
SENSE Low-Side
Registers
V RANGE
OUT
ISense
Soft-
Current
Start
Low-Side
OUTSNS
Limit
Current
R2
Limit
PG
REF CLK SLOPE
DAC
DLY
Oscillator
Gm
and
Error
Power-Good
V
IN
Slope
Amplifier
Comparator
OUTSNS
Compensation
R1
A COMP
GND
DS20005568A-page 2 2016 Microchip Technology Inc.
LX V
INLDO
BST
V
DDP
PG V
DDA
EN
ADR0
ADR1
OUTSNS