RT9202CS datasheet(6/16 Pages) RICHTEK

6 / 16 page

RT9202

www.richtek.com

DS9202-02 August 2002

Parameter

Symbol

Test Conditions

Min

Typ

Max

Units

Protection

FB Over-Voltage Trip

FB Rising

1.0

1.1

FB Under-Voltage Trip

FB Falling

0.5

0.6

OCSET Current Source

IOCSET

VOCSET= 4.5V

µA

Soft-Start Interval

Functional Pin Description

BOOT (Pin 1)

This pin provides ground referenced bias voltage to the

upper MOSFET driver. A bootstrap circuit is used to

create a voltage suitable to drive a logic-level N-

channel MOSFET when operating at a single 5V power

supply. This pin also could be powered from ATX 12V,

in this situation, a internal 6.0V regulator will supply to

VCC pin for internal voltage bias.

UGATE (Pin 2)

Connect UGATE pin to the PWM converter’s upper

MOSFET gate. This pin provides the gate drive for the

upper MOSFET.

GND (Pin 3)

Signal and power ground for the IC. All voltage levels

are measured with respect to this pin.

LGATE (Pin 4)

Connect LGATE to the PWM converter’s lower

MOSFET gate. This pin provides the gate drive for the

lower MOSFET.

VCC (Pin 5)

This is the main bias supply for the RT9202. This pin

also provides the gate bias charge for the lower

MOSFETs gate. The voltage at this pin monitored for

power-on reset (POR) purpose. This pin is also the

internal 6.0V regulator output powered from BOOT pin

when BOOT pin is directly powered from ATX 12V.

FB (Pin 6)

This pin is connected to the PWM converter’s output

divider. This pin also connects to internal PWM error

amplifier inverting input and protection monitor.

OCSET (Pin 7)

Connect a resistor from this pin to the drain of the

respective upper MOSFET. This resistor, an internal

µA current source, and the upper MOSFET on-

resistance set the converter over-current trip point. An

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

voltage at this pin is monitored for power-on reset

(POR) purpose and pulling this pin low with an open

drain device will shut down the IC.

PHASE (Pin 8)

This pin is used to monitor the voltage drop across the

upper MOSFET for over-current protection.

)

(

OCSET

PEAK

RT9202CS Datasheet(PDF) 6 Page - Richtek Technology Corporation

RT9202CS Datasheet(HTML) 6 Page - Richtek Technology Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Datasheet Download

Link URL