Copyright

© ANPEC Electronics Corp.

Rev. A.7 - Oct., 2011

APW7098

www.anpec.com.tw

1

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.

Two- Phase Buck PWM Controller with Integrated MOSFET Drivers

Features

•

Voltage-Mode Operation with Current Sharing

- Adjustable Feedback Compensation

- Fast Load Transient Response

•

Operate with 8V~13.2V

•

Selectable External or Internal 0.6V Reference

- ±1.5% Accuracy Over Temperature

•

Support Single- and Two-Phase Operations

•

5VCC and Buffered Reference Outputs

•

8~12V Gate Drivers with Internal Bootstrap

Diode

•

Lossless Inductor DCR Current Sensing

•

Selectable Operation Frequency

- 150k/300k/400kHz per Phase

•

Power-OK Indicator Output

- Regulated 1.5V on REFOUT/POK

•

Adjustable Over-Current Protection (OCP)

•

Accurate Load Line (DROOP) Programming

•

Adjustable Soft-Start

•

Over-Voltage Protection (OVP)

•

Under-Voltage Protection (UVP)

•

Over-Temperature Protection (OTP)

•

QFN4x4 24-Lead Package (QFN4x4-24A)

•

Lead Free and Green Devices Available

(RoHS Compliant)

Applications

General Description

The APW7098, two-phase PWM control IC, provides a

precision voltage regulation system for advanced graphic

microprocessors in graphics card 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 APW7098 uses a voltage-mode PWM architecture,

operating with fixed-frequency, to provides excellent load

transient response. The device uses the voltage across

the DCRs of the inductors for current sensing. Load line

voltage positioning (DROOP), channel-current balance,

and over-current protection are accomplished through

continuous inductor DCR current sensing.

The MODE pin programs single- or two- phase operation.

When IC operates in two-phase mode normally, it can

transfer two-phase mode to single-phase mode at liberty.

Nevertheless, once operates in single-phase mode, the

operation mode is latched. It is required to toggle SS,

REFIN/EN or 5VCC pin to reset the IC. Such feature of the

MODE pin makes the APW7098 ideally suitable for dual

power input applications, such as PCIE interfaced graphic

cards.

This control IC‘s protection features include a set of

sophisticated over-temperature, over-voltage, under-

voltage, and over-current protections. Over-voltage re-

sults in the converter turning the lower MOSFETs on to

clamp the rising output voltage and protects the

microprocessor. The over-current protection level is set

through external resistors. 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 APW7098 is available in a QFN4x4-24A package.

•

Graphics Card GPU Core Power Supply

•

Motherboard Chipset or DDR SDRAM Core Power

Supply

•

On-board High Power PWM Converter with Out-

put Current up to 60A

Simplified Application Circuit

V

IN1

V

IN2

V

OUT

FB

COMP

APW7098

REFIN/EN

REFOUT/POK