RT8800A

2

DS8800A-04 August 2007

www.richtek.com

All brand name or trademark belong to their owner respectively

Functional Pin Description

IMAX (Pin 1)

Over current protection setting.

VID125 (Pin 2)

FB (Pin 3)

The pin is defined as the inverting input of internal error

amplifier.

DVD (Pin 4)

The pin is defined as a programmable power UVLO

COMP (Pin 5)

The pin is defined as the output of the error amplifier and

the input of all PWM comparators.

PI (Pin 6)

The pin is defined as the positive input of the error amplifier.

RT (Pin 7)

Switching frequency setting. Connect this pin to GND with

a resistor to set the frequency.

ICOMMON (Pin 8)

Common negative input of current sense amplifiers for all

three channels.

PGOOD (Pin 9)

Output power-good indication. The signal is implemented

as an output signal with open-drain type.

ISP1 , ISP2 , ISP3 (Pin 12, Pin 11, Pin 10)

Current sense positive inputs for individual converter

channel current sense.

PWM1 , PWM2 , PWM3 (Pin 13, Pin 14, Pin 15)

PWM outputs for each phase switching drive.

VDD (Pin 16)

Chip power supply. Connect this pin to a 5V supply.

GND [Exposed Pad (17)]

The exposed pad must be soldered to a large PCB and

connected to GND for maximum power dissipation.

Pin Configurations

(TOP VIEW)

VQFN-16L 3x3

IMAX

ISP1

PGOOD

ISP3

ISP2

DVD

FB

VID125

12

11

10

9

13

14

15

16

1

2

3

4

8

7

6

5

GND

17