APW8728 Datasheet, PDF (1/25 Pages) Anpec Electronics Coropration – VGA PWM Controller with Differential Voltage Feedback

APW8728
VGA PWM Controller with Differential Voltage Feedback
Features
General Description
• Adjustable Output Voltage from +0.6V to +3.3V
The APW8728 is a single-phase, constant on-time,
- 0.6V Reference Voltage
synchronous PWM controller, which drives N-channel
- ±0.6% Accuracy Over-Temperature
MOSFETs. The APW8728 steps down high voltage to
• Operates from An Input Battery Voltage Range of ^{generate low-voltage chipset or RAM supplies in notebook}
+1.8V to +28V
computers.
• Remote Feedback Sense for Excellent Output ^{The APW8728 provides excellent transient response and}
Voltage
accurate DC voltage output in either PFM or PWM Mode.
In Pulse Frequency Mode (PFM), the APW8728 provides
• REFIN Function for Over-clocking Purpose from _{very high efficiency over light to heavy loads with loading-}
0.5V~2.5V range
modulated switching frequencies. In PWM Mode, the
• Power-On-Reset Monitoring on VCC pin
converter works nearly at constant frequency for low-noise
• Excellent line and load transient responses
requirements. APW8728 is built in remote sense function
• PFM mode for increased light load efficiency
for applications that require remote sense.
• Programmable PWM Frequency from 100kHz to ^{The APW8728 is equipped with accurate positive current}
500kHz
limit, output under-voltage, and output over-voltage
• Selectable Forced PWM or automatic PFM/PWM ^{protections, perfect for NB applications. The Power-On-}
Reset function monitors the voltage on VCC to prevent
mode
wrong operation during power-on. The APW8728 has a
• Built in 30A Output current driving capability
1ms digital soft start and built-in an integrated output
• Integrate MOSFET Drivers
discharge device for soft stop. An internal integrated soft-
• Integrated Bootstrap Forward P-CH MOSFET
start ramps up the output voltage with programmable
• Adjustable Integrated Soft-Start and Soft-Stop
slew rate to reduce the start-up current. A soft-stop function
• Power Good Monitoring
actively discharges the output capacitors.
• 70% Under-Voltage Protection
• 125% Over-Voltage Protection
The APW8728 is available in 16pin TQFN3x3-16 package
respectively.
• TQFN3x3-16 Package
• Lead Free and Green Devices Available
Simplified Application Circuit
(RoHS Compliant)
V_CC=5V ^{EN REFIN RTON}
V_IN
Applications
• Notebook
• Table PC
• Hand-Held Portable
• AIO PC
TON
RPOK
UGATE
Q1
POK
APW8728
VOUT
L
PHASE
RTN
OCSET
LGATE
Q2
V_OUT
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.2 - Dec., 2012
www.anpec.com.tw