Dual-Phase COT Buck PWM Controller
Support Wide Input Voltage Range from 5.4V to
VCC Support Range from 4.5V to 5.5V
Integrated High-side MOSFET Driver with Integrat-
ed Bootstrap P-CHMOSFET
Drive N-CH MOSFET with built in Adaptive Dead
Time Control Scheme
Support Single-PFM, Two Phase PWM, and Ultra
-sonic PFM mode
PWM Switching Frequency 500KHz ~700KHz by
Built in Constant On Time PWM Control with Cur-
rent Balance Operation
Support Single and Two Phase PWM Control by
LGATE2 & PSI Voltage Setting
Built in Adjustable Over Current Protection by
Built in Under Voltage Protection with Latch off
Built in Over Voltage Protection with Latch off
Built in Over Temperature Protection
Individual EN & POK indicator
Built in VID for VOUT adjustment
Built in decay down mode.
TQFN 4x4-24 Package
The APW8731C is a dual-phase PWM control IC which
provides a precision voltage regulation system and sup-
ports wide input range from 5.4V to 24V. By integrating
dual-phase power MOSFET drivers and controller into the
one IC, APW8731C can reduce the number of external
components for a cost and space saving power manage-
The APW8731C's PWM controller adopts constant on
time architecture which has the trait of excellent transient
resposnse. The PWM controller features automatic phase
reduction that can either operates in dual-phase mode or
single-phase mode, depending on resistor settings on PSI
and LGATE2 pin. The resistor on LGATE2 pin can also
set PWM/PFM/USM operations. The device integrates
adjustable load line voltage positioning (droop) and detect
voltage on low side RDS(ON) for channel-current balance.
The protection functions include over current protection
(OCP), under voltage protection (UVP), over voltage
protection (OVP) and over temperature protection (OTP).
OCP, UVP or OVP occurrence will lead to latch-off. A
thermal shutdown function is implemented to prevent
damages due to heat by excessive power dissipation.
Typically the thermal shutdown threshold temperature
is 150oC.When the thermal shutdown is triggered the
device stops switching and output voltage re-start after
the junction temperature cools by 30oC. APW8731C is
packaged in TQFN 4x4-24.
●● Graphic card
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise cus-
tomers to obtain the latest version of relevant information to verify before placing orders.
CopyrightANPEC Electronic Corp.
Rev. A.2 - Jul., 2019