UTC3521

CMOS IC

1

www.unisonic.com.tw

QW-R502-034,A

PWM CONTROLLER WITH SUPERVISORY

CIRCUIT FOR SWITCHING POWER

SUPPLY

DESCRIPTION

UTC 3521 PWM controller is designed for switching mode

power supply for PCs etc. It provides all the functions similar

to combinations of industrial 494 plus 3510 circuits.

FEATURES

* Over-voltage protection for 3.3V, 5V and 12V with delay

* Under-voltage detection for 3.3V, 5V and 12V with delay

* Remote ON/OFF function

* Power good circuitry for PCs.

DIP-16

*Pb-free plating product number: 3521L

PIN CONFIGURATION

V33

V5

V12

PT

GND

CT

C1

C2

VADJ

OPNEGIN

OPOUT

DET

PG

TPG

REM

UTC 3521

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

PIN DESCRIPTION

PIN NO.

PIN NAME

TYPE

FUNCTIONS

1

V33

I

OVP/UVP INPUT FOR 3.3V

2

V5

I

OVP/UVP INPUT FOR 5V

3

V12

I

OVP/UVP INPUT FOR 12V

4

PT

I

ADDITIONAL OVP PROTECTION

5

GND

P

GROUND

6

CT

CAP FOR OSCIILATION FREQUENCY

7

C1

O

OUTPUT 1

8

C2

O

OUTPUT 2

9

REM

I

REMOTE ON/OFF PIN.

10

TPG

POWER GOOD DELAY TIME SETTING

11

PG

O

POWER GOOD SIGNAL OUT.

12

DET

I

POWER GOOD SIGNAL DETECTION INPUT

13

VCC

P

SUPPLY VOLTAGE FOR IC

14

OPOUT

O

OP AMP OUTPUT

15

OPNEGIN

I

OP AMP NEGATIVE INPUT

16

VADJ

I

VOLTAGE ADJUST PIN