AP1511

PWM Control 5A Step-Down Converter

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 Mar 4, 2005

1/5

Features

- Input voltage: 3.6V to 23V.

- Duty ratio: 0% to 100% PWM control

- Oscillation frequency: 300KHz typ.

- Soft-start, Current limit, Enable function

- Thermal Shutdown function

- Built-in internal SW P-channel MOS

- SOP-16L Pb-Free Package.

Applications

-Microprocessor core supply

-Networking power supply

-LCD MNT, TV power supply

-Telecom power supply

General Description

AP1511 consists of step-down switching regulator

with PWM control. These devices include a reference

voltage source, oscillation circuit, error amplifier,

internal PMOS and etc.

AP1511 provides low-ripple power, high efficiency,

and excellent transient characteristics. The PWM

control circuit is able to very the duty ratio linearly

from 0 up to 100%. This converter also contains an

error amplifier circuit as well as a soft-start circuit that

prevents overshoot at startup. An enable function,

an over current protect function and a short circuit

protect function are built inside, and when OCP or

SCP happens, the operation frequency will be

reduced from 300KHz to 30KHz. Also, an internal

compensation block is built in to minimum external

component count.

With the addition of an internal P-channel Power MOS,

a coil, capacitors, and a diode connected externally,

these ICs can function as step-down switching

regulators. They serve as ideal power supply units for

portable devices when coupled with the SOP-16L

mini-package, providing such outstanding features as

low current consumption. Since this converter can

accommodate an input voltage up to 23V, it is also

suitable for the operation via an AC adapter.

Pin Assignments

AP1511

1

2

3

15

14

13

12

11

10

9

8

7

6

5

4

16

(Top View)

SOP-16L

GND

GND

Vref

(Comp)

V

C

PVcc

Output

Output

GND

GND

FB

EN

OCSET

Vcc

Output

Output

Pin Descriptions

Pin

Name

Pin

No.

Description

GND

1

GND pin

GND

2

GND pin

FB

3

Feedback pin

EN

4

H: Normal operation

L: Step-down operation stopped

OCSET

5

Add an external resistor to set max

output current.

Vcc

6

Signal Vcc

Output

7

Switch output pin

Output

8

Switch output pin

Output

9

Switch output pin

Output

10 Switch output pin

PVcc

11

Power Vcc

12 Voltage clamp pin

Vref

13 Reference voltage

(Comp)

14 Option for comp

GND

15 GND pin

GND

16 GND pin