RT7249

2

DS7249-02 March 2017

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©

Copyright 2017 Richtek Technology Corporation. All rights reserved.

is a registered trademark of Richtek Technology Corporation.

Function Pin Description

Pin No.

Pin Name

Pin Function

1

SS

Soft-start time setting. SS controls the soft-start period. Connect a capacitor from SS

to GND to set the soft-start period. An internal current source (6

A) charges 0.1F

capacitor and sets the soft-start period to 13.5ms. If SS is floating, the SS charge

current will decrease to 1/128

A and charge 30pF capacitor to set the soft-start

period to 4ms.

2

COMP

Compensation node. COMP is used to compensate the regulation control loop.

Connect a series RC network from COMP to GND. In some cases, an additional

capacitor from COMP to GND is required.

3

ROSC

Switching frequency setting.

4

RLIM

Current limit setting. Switch current limit threshold can be set by an external resistor.

Current limit value is from 75mA to 2580mA. The value of 10k

recommended.

5

EN_SW

Enable control input for power switch.

Applications



Wireless AP/Router



Set-Top-Boxes



Industrial and Commercial Low Power Systems



LCD Monitors and TVs



Green Electronics/Appliances



Point of Load Regulation of High-Performance DSPs



USB Bus/Self Powered Hubs



USB Peripheral Ports



ACPI Power Distribution



Battery Power Equipment



3G/3.5GData Card

Ordering Information

Note :

Richtek products are :



RoHS compliant and compatible with the current require-

ments of IPC/JEDEC J-STD-020.



Suitable for use in SnPb or Pb-free soldering processes.

RT7249

Package Type

QW : WQFN-16L 4x4 (W-Type)

Lead Plating System

G : Green (Halogen Free and Pb Free)

Pin Configuration

WQFN-16L 4x4

(TOP VIEW)

SS

COMP

ROSC

RLIM

SW_IN

BOOT

LX

FB

1

2

3

4

56

7

8

12

11

10

9

13

16

14

15

17

PGND