APW7065_09 Datasheet, PDF (1/21 Pages) Anpec Electronics Coropration – Synchronous Buck PWM Controller

APW7065
Synchronous Buck PWM Controller
Features
General Description
• Single 12V Power Supply Required
• Fast Transient Response
- 0~90% Duty Ratio
• 0.8V Reference with 1% Accuracy
• Shutdown Function by Controlling COMP Pin Volt-
age
• Internal Soft-Start (3.4ms) Function
• Voltage Mode PWM Control Design
• Under-Voltage Protection
• Over-Current Protection
- Sense Low Side MOSFET’s R_DS(ON)
• 300kHz Fixed Switching Frequency
• SOP-8 Package
• Lead Free and Green Devices Available
(RoHS Compliant)
Applications
• Graphics Card
• Mother Board
Pin Configuration
APW7065
BOOT 1
UGATE 2
GND 3
LGATE ⁴
8 PHASE
7 COMP
6 FB
5 VCC
The APW7065 uses fixed 300kHz switching frequency,
voltage mode, and synchronous PWM controller which
drives dual N-channel MOSFETs. The device integrates
the control, monitoring and protection functions into a
single package, provides one controlled power output
with under-voltage and over-current protections.
The APW7065 provides excellent regulation for output load
variation. The internal 0.8V temperature-compensated
reference voltage is designed to meet the requirement of
low output voltage applications. An built-in digital soft-
start with fixed soft-start interval prevents the output volt-
age from overshoot as well as limiting the input current.
The APW7065 with excellent protection functions: POR,
OCP and UVP. The Power-On-Reset (POR) circuit can
monitor VCC supply voltage exceeds its threshold volt-
age while the controller is running, and a built-in digital
soft-start provides output with controlled voltage rise. The
Over-Current Protection (OCP) monitors the output cur-
rent by using the voltage drop across the lower MOSFET’s
R_DS(ON), comparing with internal V_OCP (0.29V), when the
output current reaches the trip point, the controller will
run the soft-start function until the fault events are
removed. The Under-Voltage Protection (UVP) monitors
the voltage of FB pin for short-circuit protection, when the
V_FB is less than 50% of V_REF (0.4V), the controller will shut-
down the IC directly.
Simplified Application Circuit
12V
V_IN
SOP-8
(Top View)
APW7065
L
V_OUT
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.6 - Aug., 2009
www.anpec.com.tw