RT2528

2

DS2528-03 November 2013

www.richtek.com

©

Copyright 2013 Richtek Technology Corporation. All rights reserved.

is a registered trademark of Richtek Technology Corporation.

Function Block Diagram

Functional Pin Description

Pin No.

Pin Name

Pin Function

1, 2

VOUT

Output.

3

ILIM

Current Limit Setting. Connect an external resistor to set current limit threshold.

The recommended resistance range is 10k

4

FAULT

Active-Low Open-Drain Output. Asserted during over-current, over-temperature, or

reverse-voltage conditions.

5

EN

Enable Control Input. Logic high turns on the power switch.

6,

9 (Exposed Pad)

GND

Ground. The exposed pad must be soldered to a large PCB and connected to GND

for maximum power dissipation.

7, 8

VIN

Power Input. Connect a 10

F or greater ceramic capacitor from the VIN to GND as

close to the IC as possible.

Operation

The RT2528 is a current-limited power switch using

P-MOSFETs for applications where short-circuit or heavy

capacitive loads will be encountered. These devices allow

users to adjust the current limit threshold between 500mA

and 2.5A (typ.) via an external resistor. Additional device

shutdown features include over-temperature protection and

reverse-voltage protection.

The RT2528 provides built-in soft-start function. The driver

controls the gate voltage of the power switch. The driver

incorporates circuitry that controls the rising time and

falling time of the output voltage to limit large inrush current

and voltage surges. The RT2528 enters constant-current

mode when the load exceeds the current limit threshold.

UVLO

Current

Limit

7.5ms

Deglitch

4ms

Deglitch

Thermal

Sense

Drive

Reverse Voltage

Comparator

Switch

well

Current

Sense

+

-

VOUT

ILIM

GND

VIN

FAULT

EN