APW8700 Datasheet, PDF (1/26 Pages) Anpec Electronics Coropration – Dual-Phase Synchronous-Rectifier Buck Controller

APW8700
Dual-Phase Synchronous-Rectifier Buck Controller
Features
General Description
• Voltage-Mode Operation with Current Sharing
• Operate with 4.5V~13.2V Supply Voltage
• Support Single and Two-Phase Operations
• +2% Reference Voltage Accuracy Over
Temperature
• Loss-Less Inductor DCR Current Sensing
• Adjustable Over Current Protection use DCR
Current Sensing
• Programmable PWM Switching Frequency from
100kHz to 800kHz
• Dynamic Output Voltage Adjustment
• Adjustable Soft-start
• QFN4x4-24 Package
• Halogen and Lead Free Available (RoHS Compliant)
Simplified Application Circuit
The APW8700, two-phase PWM control IC, provides a
precision voltage regulation system for advanced graphic
card and motherboard applications. The integration of
power MOSFET drivers into the controller IC and reduces
the number of external parts for a cost and space saving
power management solution.
The APW8700 uses a voltage-mode PWM architecture,
operating with adjust frequency from 100kHz to 800kHz.
The device uses the voltage across the DCRs of the in-
ductors for current sensing achieves high efficiency. The
device integrates adjustable load line voltage position-
ing (droop) and adopts low side R_{DS_ON} for channel-cur-
rent balance.
The automatic phase reduction and over-current protec-
tion are accomplished through continuous inductor DCRs
current sensing.
The APW8700 also implement a one-bit VID control op-
eration in which the feedback voltage is regulated and
tracks external input reference voltage.
This controller protection features include over-
temperature(OTP), over-voltage(OVP), under-voltage
(UVP) and over-current protections (OCP).
The device also provides a power-on-reset function and
a programmable soft-start to prevent wrong operation and
limit the input surge current during power-on or start-up.
The APW8700 is available in QFN4x4-24 packages.
Applications
• VGA
• Mother Board
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.1 - Jun., 2011
www.anpec.com.tw