APW7120A Datasheet, PDF (1/22 Pages) Anpec Electronics Coropration – 5V to 12V Supply Voltage, 8-PIN, Synchronous Buck PWM Controller

APW7120A
5V to 12V Supply Voltage, 8-PIN, Synchronous Buck PWM Controller
Features
General Description
• Operating with Single 5~12V Supply Volt-
age 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
• ±2% 0.8V Reference
- Over Line, Load Regulation, and
Operating Temperature
• 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 and Green Devices Available
(RoHS Compliant)
Applications
The APW7120A is a fixed 300kHz frequency, voltage
mode, and synchronous PWM controller. The device
drives two low cost N-channel MOSFETs and is de-
signed to work with single 5~12V or two supply
voltage(s), providing excellent regulation for load
transients.
The APW7120A 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’s over-current protection
monitors the output current by using the voltage drop
across the low-side MOSFET’s R , eliminating the
DS(ON)
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.
Pin Cinfiguration
• Motherboard
• Graphics Card
• High Current, up to 20A, DC-DC Converters
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.
1
Rev. A.2 - Jun., 2008
www.anpec.com.tw