Pin Assignment

Pin Description

Pin No.

Pin Name

I/O

Description

1

VSEN

I

This pin is connected to the converters output voltage. The

PGOOD and OVP comparator circuits use this signal to report

output voltage status and for overvoltage protection.

2

OCSET

I

converter over-current (OC) trip point.

I= IR

r

PEAK

OCS

OCSET

DS(ON)

´

An over-current trip cycles the soft-start function.

3SS

O

Connect a capacitor from this pin to ground. This capacitor,

along with an internal 10mA current source, sets the soft-start

interval of the converter.

4~8

VID0~4

I

VID0-4 are the input pins to the 5-bit DAC. The states of these

five pins program the internal voltage reference (DACOUT).

The level of DACOUT sets the converter output voltage. It also

sets the PGOOD and OVP thresholds. Table 1 specifies

DACOUT for the 32 combinations of DAC inputs.

9, 10

COMP, FB

I

COMP and FB are the available external pins of the error ampli-

fier. The FB pin is the inverting input of the error amplifier and

the COMP pin is the error amplifier output. These pins are used

to compensate the voltage-control feedback loop of the con-

verter.

11

GND

P

Signal ground for the IC. All voltage levels are measured with

respect to this pin.

HT82P604B

2

March 23, 2000

Preliminary

VS EN

OC S E T

SS

VI D 0

VI D 1

VI D 2

VI D 3

VI D 4

CO M P

FB

RT

OV P

VC C

LG A T E

PG N D

BO O T

UG A T E

PH AS E

P G OOD

GN D

20

19

18

17

16

15

14

13

12

11

1

2

3

4

5

6

7

8

9

10

H T 82P 6 04B

20 S O P