APW7098
Two- Phase Buck PWM Controller with Integrated MOSFET Drivers
Features
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Voltage-Mode Operation with Current Sharing
- Adjustable Feedback Compensation
- Fast Load Transient Response
Operate with 8V~13.2V
CC
Supply Voltage
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)
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‘ protection features include a set of
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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.
Simplified Application Circuit
V
IN1
V
OUT
REFIN/EN
REFOUT/POK
APW7098
COMP
FB
V
IN2
Applications
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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
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.6 - Oct., 2009
1
www.anpec.com.tw