LD7538

2

Leadtrend Technology Corporation

LD7538-DS-00

November 2012

Pin Configuration

DIP-8 (TOP VIEW)

SOT-26 (TOP VIEW)

YY, Y

: Year code (D: 2004, E: 2005

…..)

WW, W : Week code

PP

: Production code

P38

: LD7538

1

2

3

4

5

6

GND COMP OTP

OUT

VCC

CS/OVP

YWP

1

8

2

3

4

7

6

5

TOP MARK

YYWWPP

YYWWPP

38

pp

Ordering Information

Part number

Package

Top Mark

Shipping

LD7538 GL

SOT-26

Green Package

YWP/38

3000 /tape & reel

LD7538 GN

DIP-8

Green Package

LD7538 GN

3600 /tube /Carton

Protection Mode

Switching Freq.

OLP

VCC OVP

CS OVP

OTP Pin

65kHz

Auto recovery

Latch

Latch

Latch

Pin Descriptions

PIN

SOT-26

PIN

DIP-8

NAME

FUNCTION

1

8

GND

Ground

2

7

COMP

Voltage feedback pin (same as the COMP pin in UC384X). Connect a

photo-coupler to close the control loop and achieve the regulation.

3

5

OTP

Pull this pin below 0.95V to shut down the controller into latch mode until the

AC resumes power-on. Connecting this pin to ground with NTC will achieve

OTP protection. Let this pin float or connect a 100k

 resistor to disable the

latch protection.

4

4

CS/OVP

Current sense pin, connect it to sense the MOSFET current. This pin is also

connected to an auxiliary winding of the PWM transformer through a resistor

and a diode for output over-voltage protection.

5

2

VCC

Supply voltage pin

6

1

OUT

Gate drive output to drive the external MOSFET