APW7145
3A, 12V, Synchronous-Rectified Buck Converter
Features
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Wide Input Voltage from 4.3V to 14V
Output Current up to 3A
Adjustable Output Voltage from 0.8V to V
IN
- ±2% System Accuracy
55mΩ Integrated Power MOSFETs
High Efficiency up to 95%
- Automatic Skip/PWM Mode Operation
Current-Mode Operation
- Easy Feedback Compensation
- Stable with Low ESR Output Capacitors
- Fast Load/Line Transient Response
General Description
The APW7145 is a 3A synchronous-rectified Buck con-
verter with integrated 55mΩ power MOSFETs. The
APW7145, designed with a current-mode control scheme,
can convert wide input voltage of 4.3V to 14V to the out-
put voltage adjustable from 0.8V to VIN to provide excel-
lent output voltage regulation.
For high efficiency over all load current range, the
APW7145 is equipped with an automatic Skip/PWM mode
operation. At light load, the IC operates in the Skip mode,
which keeps a constant minimum inductor peak current,
to reduce switching losses. At heavy load, the IC works in
PWM mode, which inductor peak current is programmed
by the COMP voltage, to provide high efficiency and ex-
cellent output voltage regulation.
The APW7145 is also equipped with power-on-reset, soft-
start, soft-stop, and whole protections (under-voltage,
over-voltage, over-temperature, and current-limit) into a
single package. In shutdown mode, the supply current
drops below 3µA.
This device, available SOP-8P and DFN4x4-8 packages,
provides a very compact system solution with minimal
external components and PCB area.
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Power-On-Reset Monitoring
Fixed 500kHz Switching Frequency in PWM Mode
Built-in Digital Soft-Start and Soft-Stop
Current-Limit Protection with Frequency Foldback
118% Over-Voltage Protection
Hiccup-Mode 50% Under-Voltage Protection
Over-Temperature Protection
<3µA Quiescent Current in Shutdown Mode
SOP-8P and Compact 4mmx4mm DFN-8
(DFN4x4-8) Packages
Lead Free and Green Devices Available
(RoHS Compliant)
100
90
80
70
60
50
40
30
20
10
0
0.001
V
IN
=12V, V
OUT
=2V, L1=3.3µF
Applications
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OLPC, UMPC
Notebook Computer
Handheld Portable Device
Step-Down Converters Requiring High Efficiency
and 3A Output Current
V
IN
=5V, V
OUT
=3.3V, L1=2.2µF
V
IN
=12V, V
OUT
=5V, L1=6.8µF
V
IN
=12V, V
OUT
=3.3V, L1=4.7µF
V
IN
=5V, V
OUT
=1.2V, L1=2.2µF
0.01
0.1
1
10
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
Copyright
©
ANPEC Electronics Corp.
Rev. A.3- Sep., 2008
1
www.anpec.com.tw
ANPEC [ ANPEC ELECTRONICS COROPRATION ]
