APW7088 Datasheet, PDF (1/25 Pages) Anpec Electronics Coropration – Two-Phase Buck PWM Controller with Integrated MOSFET Drivers

APW7088
Two-Phase Buck PWM Controller with Integrated MOSFET Drivers
Features
General Description
• Voltage-Mode Operation with Current Sharing
- Adjustable Feedback Compensation
- Fast Load Transient Response
• Operate with 8V~13.2V_CC Supply Voltage
• Programmable 3-Bit DAC Reference
-±1.5% System Accuracy Over Temperature
• Support Single- and Two-Phase Operations
• 5V Linear Regulator Output on 5VCC
• 8~12V Gate Drivers with Internal Bootstrap Diode
• Lossless Inductor DCR Current Sensing
• Fixed 300kHz Operating Frequency Per Phase
• Power-OK Indicator Output
- Regulated 1.5V on 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 (QFN4x4-24)
• Lead Free and Green Devices Available
(RoHS Compliant)
Simplified Application Circuit
VID0
VID1
VID2
V_IN1
APW7088
POK
COMP
FB
V_IN2
V_OUT
The APW7088, two-phase PWM control IC, provides a
precision voltage regulation system for advanced graphic
microprocessors in graphics card applications. The inte-
gration of power MOSFET drivers into the controller IC
reduces the number of external parts for a cost and space
saving power management solution.
The APW7088 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 or
5VCC pin to reset the IC. Such feature of the MODE pin
makes the APW7088 ideally suitable for dual power input
applications, such as PCIE interfaced graphic cards.
This control IC‘s protection features include a set of so-
phisticated over temperature, over-voltage, under-voltage,
and over-current protections. Over-voltage results 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 func-
tion and a programmable soft-start to prevent wrong op-
eration and limit the input surge current during power-on
or start-up.
The APW7088 is available in a QFN4x4-24 package.
Applications
• 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.
1
Rev. A.4 - Feb., 2009
www.anpec.com.tw