POWER MANAGEMENT

1

www.semtech.com

SC1205

High Speed Synchronous

Power MOSFET Driver

Features

Applications

Revision: September 22, 2004

Description

The SC1205 is a cost effective Dual MOSFET Driver de-

signed for switching High and Low side Power MOSFETs.

Each driver is capable of driving a 3000pF load in 20ns

max rise/fall time and has a 20ns max propagation de-

lay from input transition to the gate of the power FET’s.

An internal Overlap Protection circuit prevents shoot-

through from Vin to GND in the main and synchronous

MOSFET’s. The Adaptive Overlap Protection circuit en-

sures the Bottom FET does not turn on until the Top FET

source has reached a voltage low enough to prevent

cross-conduction.

The high current drive capability (3A peak) allows fast

switching, thus reducing switching losses at high (up to

1MHz) frequencies without overheating the driver. The

high voltage CMOS process allows operation from 5-25

Volts at top MOSFET drain, thus making SC1205 suit-

able for battery powered applications. Connecting En-

able pin (EN) to logic low shuts down both drives and

reduces operating current to less than 10uA.

An Under-Voltage-Lock-Out circuit is included to guaran-

tee that both driver outputs are low when the 5V logic

level is less than or equal to 4.4V (typ) at supply ramp up

(4.35V at supply ramp down). An Internal temperature

sensor shuts down all drives in the event of

overtemperature. SC1205 is fabricated utilizing Bi-CMOS

technology for low quiescent current. The SC1205 is of-

fered in a standard SO-8 package.

Fast rise and fall times (15ns typical with 3000pf

load)

3 Amp peak drive current

14ns max Propagation delay (BG going low)

Adaptive Non-overlapping Gate Drives provide

shoot-through protection

Floating top drive switches up to 25V

Under-Voltage lock-out

Overtemperature protection

Low cost

High Density sunchronous power supplies

Motor Drives/Class-D amps/Half bridge drivers

High frequency (to 1.2 MHz) operation allows use

of small inductors and low cost caps in place of

electrolytics

High efficiency portable computers

Battery powered applications

Typical Application Circuit

Vcore, 1.7v,40A

+5V

Vin 5-12V

Rf

Rref

Ri

10nf

2.5m

10

SC2422A

12

9

2

3

1

13

7

5

6

11

14

4

10

15

16

8

OUT2

GND

VID3

VID2

VID4

OUT1

FB

VID0

ERROUT

OC-

OC+

VID1

UVLO

BGOUT

VCC

RREF

70N03

SC1205

CO

TG

DRN

VS

EN

BG

SC1205

CO

TG

DRN

VS

EN

BG

10u,CER

2200uf

70N03

70N03

70N03