AP1625

PWM/PFM Dual Mode Step-down DC/DC Controller

This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of

this product. No rights under any patent accompany the sale of the product.

Rev.1.1 May.27, 2004

1/5

Features

- Adjustable version（±2.5%）

- Oscillator frequency: 270KHz（±15%）

- High Efficiency: 92%（typ .）

- Soft-start time set-up externally type possible

- Output voltage type possible（FB）

- Package: SOT23-5

Applications

● Electronic Information Organizers

● Palmtops

● Cellular and portable phones

● Portable Audio Systems

● Various Multi-function Power Supplies

General Descriptions

The AP1625 series are multi-functional step-down

DC/DC converters with built-in speed, low ON

resistance drivers. A more than 1A output current is

possible using an externally connected transistor,

coil, diode and capacitor.

Output voltage is set-up by external resistor.（±2.5%

accuracy）.

With a 270KHz switching frequency, the size of the

external components can be reduced.

Control switches from PWM to PFM during light

loads with the AP1625（PWM/PFM switchable）and

the series is highly efficient from light loads to large

output currents.

In relation to soft-start time external capacitor

regulated types.

During stand-by time （CE pin “LOW”）,current

consumption is reduced to less than 0.5µA.

With U.V.L.O internal, the external MOSFET. Will

be forcibly switched off if used below the stipulated

voltage.

Pin Assignment

1

3

2

5

4

CE

V

OUT

V

DD

GND

SOT23-5

FB

(Top View)

Pin Descriptions

Pin No.

Pin

Name

Function

1

2

Power Supply

3

GND Ground

4

CE

Chip Enable

Soft-start capacitor connection

5

FB

Feedback pin