RT7305

Copyright © 2014 Richtek Technology Corporation. All rights reserved.

is a registered trademark of Richtek Technology Corporation

www.richtek.com

DS7305-00

July

2014

2

Ordering Information

RT7305

Package Type

S : SOP-7

Lead Plating System

G : Green (Halogen Free and Pb Free)

Note :

Richtek products are :



RoHS compliant and compatible with the current

requirements of IPC/JEDEC J-STD-020.



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

Marking Information

RT7305

GSYMDNN

RT7305GS : Product Number

YMDNN : Date Code

Pin Configurations

(TOP VIEW)

VDD

GND

ZCD

COMP

DRAIN

CS

SOURCE

2

3

4

5

6

7

SOP-7

Functional Pin Description

Pin No.

Pin Name

Pin Function

1

VDD

2

GND

Ground of the Controller.

3

ZCD

Zero Current Detection Input. This pin is used to sense the voltage at

auxiliary winding of the transformer.

4

COMP

Compensation Node. Output of the internal trans-conductance amplifier.

5

CS

Current Sense Input. Connect this pin to the current sense resistor.

6

SOURCE

Source terminal of the integrated power MOSFET.

7

DRAIN

Drain terminal of the integrated power MOSFET.

Function Block Diagram

COMP

DRAIN

GND

13V

Gate

Driver

Ramp

Generator

CS

ZCD

Output OVP

OTP

PWM

Clamping

Circuit

Under-Voltage

Lockout

(16V/9V)

VDD

Over-Voltage

Protection

UVLO

VDD OVP

VDD

PWM

Control

Logic

Current-Limit

Comparator

1V

Valley

Detector

Valley Signal

Constant

Current

Control

Constant-Current

Comparator

Output

Over-Voltage

Protection

Over-

Temperature

Protection

Leading

Edge

Blanking

Output Diode

Short-Circuit

Protection

Starter

Circuit

SOURCE

Integrated

MOSFET

+

-

+

-