Microsemi

Analog Mixed Signal Group

11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570

1

SG1842/SG1843 Series

Copyright

© 2000

Rev. 1.6b 2010-03-15

DESCRIPTION

The SG1842/43 family of control IC's provides all

the necessary features to implement off-line fixed

frequency, current-mode switching power supplies

with a minimum number of external components.

Current-mode architecture demonstrates improved

line regulation, improved load regulation, pulse-

by-pulse current limiting and inherent protection

of the power supply output switch. The bandgap

reference is trimmed to ±1% over temperature.

Oscillator discharge current is trimmed to less

than ±10%. The SG1842/43 has under-voltage

lockout, current limiting circuitry and start-up

current of less than 1mA. The totem-pole output

is optimized to drive the gate of a power

MOSFET. The output is low in the off state to

provide direct interface to an N channel device.

The SG1842/43 is specified for operation over

the full military ambient temperature range of -

55°C to 125°C. The SG2842/43 is specified for

the industrial range of -25°C to 85°C, and the

SG3842/43 is designed for the commercial range

of 0°C to 70°C.

IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com

PRODUCT HIGHLIG HT

AC

INPUT

SG3842

R

ST

I

ST

V

CC

KEY FEA T URES

OPTIMIZED FOR OFF-LINE

CONTROL

LOW START-UP CURRENT (<1mA)

AUTOMATIC FEED FORWARD

COMPENSATION

TRIMMED OSCILLATOR

DISCHARGE CURRENT

PULSE-BY-PULSE CURRENT

LIMITING

ENHANCED LOAD RESPONSE

CHARACTERISTICS

UNDER-VOLTAGE LOCKOUT

WITH 6V HYSTERESIS (SG1842

only)

DOUBLE-PULSE SUPPRESSION

HIGH-CURRENT TOTEM-POLE

OUTPUT (1AMP PEAK)

INTERNALLY TRIMMED BANDGAP

REFERENCE

500KHZ OPERATION

UNDERVOLTAGE LOCKOUT

SG1842 - 16 volts

SG1843 - 8.4 volts

LOW SHOOT-THROUGH

CURRENT <75mA OVER

TEMPERATURE

HI GH RELI ABI L I T Y

FEATURES

AVAILABLE TO MIL-STD-883B AND

DSCC

SCHEDULED FOR MIL-M38510

QPL LISTING

RADIATION DATA AVAILABLE

Microsemi LEVEL "S" PROCESSING

AVAILABLE

PACKAGE ORDER INFO

M

Plastic DIP

8-Pin

N

Plastic DIP

14-Pin

DM

Plastic SOIC

8-Pin

D

Plastic SOIC

14-Pin

Y

Ceramic Dip

8-Pin

J

Ceramic DIP

14-Pin

F

Cer Flatpack

10-Pin

L

Ceramic LCC

20-Pin

RoHS / Pb-free Transition DC: 0503

RoHS / Pb-free Transition DC:0440

SG3842M

SG3842N

SG3842DM

SG3842D

SG3842Y

SG3842J

0 to 70

SG3843M

SG3843N

SG3843DM

SG3843D

SG3843Y

SG3842J

SG2842M

SG2842N

SG2842DM

SG2842D

SG2842Y

SG2842J

-25 to 85

SG2843M

SG2843N

SG2843DM

SG2843D

SG2843Y

SG2843J

SG1842Y

SG1842J

SG1842F

SG1842L

-55 to

125

SG1843Y

SG1843J

SG1843F

SG1842L

SG1842Y/883B

SG1842J/883B

SG1842F/883B

SG1842L/883B

MIL-

STD/883

SG1843Y/883B

SG1843J/883B

SG1843F/883B

SG1843L/883B

SG1842Y/DESC

SG1842J/DESC

SG1842F/DESC

SG1842L/DESC

DESC

SG1843Y/DESC

SG1843J/DESC

SG1843F/DESC

SG1843L/DESC

Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. SG2843DM-TR)

Plastic packages are RoHS compliant

TM

®