APW7120
5V to 12V Supply Voltage, 8-PIN, Synchronous Buck PWM Controller
Features
•
•
•
Operating with Single 5~12V Supply Voltage
or two Supply Voltages
Drive Dual Low Cost N-Channel MOSFETs
- Adaptive Shoot-Through Protection
Built-in Feedback Compensation
- Voltage-Mode PWM Control
- 0~100% Duty Ratio
- Fast Transient Response
General Description
The APW7120 is a fixed 300kHz frequency, voltage
mode, synchronous PWM controller. The device drives
two low cost N-channel MOSFETs and is designed to
work with single 5~12V or two supply voltage(s),
providing excellent regulation for load transients.
The APW7120 integrates controls, monitoring and
protection functions into a single 8-pin package to
provide a low cost and perfect power solution.
A power-on-reset (POR) circuit monitors the VCC
supply voltage to prevent wrong logic controls. An
internal 0.8V reference provides low output voltage
down to 0.8V for further applications. An built-in digital
soft-start with fixed soft-start interval prevents the
output voltage from overshoot as well as limiting the
input current. The controller’ over-current protection
s
monitors the output current by using the voltage drop
across the low-side MOSFET’ R
DS(ON)
, eliminating the
s
need of a current sensing resistor. Additional under
voltage and over voltage protections monitor the
voltage on FB pin for short-circuit and over-voltage
protections. The over-current protection cycles the
soft-start function until 4 over-current events are
counted.
Pulling and holding the voltage on OCSET pin below
0.15V with an open drain device shuts down the
controller.
•
±2% 0.8V Reference
- Over Line, Load Regulation and
Operating Temp.
•
•
•
•
•
Programmable Over-Current Protection
- Using R
DS(ON)
of Low-Side MOSFET
Hiccup-Mode Under-Voltage Protection
118% Over-Voltage Protection
Adjustable Output Voltage
Small Converter Size
- 300kHz Constant Switching Frequency
- Small SOP-8 Package
•
•
•
Built-In Digital Soft-Start
Shutdown Control using an External MOSFET
Lead Free Available (RoHS Compliant)
Applications
•
•
•
Motherboard
Graphics Card
High Current, up to 20A, DC-DC Converters
Pinouts
BOOT 1
UGATE 2
GND 3
LGATE 4
8 PHASE
7 OCSET
6 FB
5 VCC
SOP-8
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.4 - Jan., 2006
1
www.anpec.com.tw