Copyright

© ANPEC Electronics Corp.

Rev. A.1 - Feb., 2012

APW8821

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.

Notebook PWM Controller with Differential Voltage Feedback

Features

•

Adjustable Output Voltage from +0.5V to +3.3V

- 0.5V Reference Voltage

- +0.6% Accuracy

•

Operates from An Input Battery Voltage Range of

+1.8V to +28V

•

Remote Feedback Sense for Excellent Output

Voltage

•

REFIN Function for Over-clocking Purpose from

0.5V~2.5V range

•

Power-On-Reset Monitoring on VCC Pin

•

Excellent line and load transient responses

•

PFM mode for increased light load efficiency

•

350kHz Constant PWM Switching Frequency

•

Integrated MOSFET Drivers

•

Integrated Bootstrap Forward P-CH MOSFET

•

Adjustable Integrated Soft-Start and Soft-Stop

•

Power Good Monitoring

•

Adjustable Current-limit protection

-Using Sense Low-Side MOSFET?¦s RDS(ON)

•

Over-Temperature Protection

•

TDFN-10 3x3 package

•

Lead Free and Green Device Available

(RoHS Compliant)

General Description

Applications

•

Notebook

•

Table PC

•

Hand-Held Portable

•

AIO PC

The APW8821 is a single-phase, constant on-time, syn-

chronous PWM controller, which drives N-channel

MOSFETs. The APW8821 steps down high voltage to

generate low-voltage chipset or RAM supplies in note-

book computers.

The APW8821 provides excellent transient response and

accurate DC voltage output in either PFM or PWM Mode.

In Pulse Frequency Mode (PFM), the APW8821 provides

very high efficiency over light to heavy loads with loading-

modulated switching frequencies. In PWM Mode, the con-

verter works nearly at constant frequency for low-noise

requirements. APW8821 is built in remote sense func-

tion for applications that require remote sense.

The APW8821 is equipped with accurate positive cur-

rent limit, output under-voltage, and output over-volt-

age protections, perfect for NB applications. The Power-

On-Reset function monitors the voltage on VCC to

prevent wrong operation during power-on. The

APW8821 has a 1ms digital soft start and built-in an

integrated output discharge device for soft stop. An

internal integrated soft-start ramps up the output volt-

age with programmable slew rate to reduce the start-

up current. A soft-stop function actively discharges the

output capacitors.

The APW8821 is available in 10pin TDFN 3x3 package

respectively.