SG1844_1 Datasheet, PDF (1/12 Pages) Microsemi Corporation – CURRENT MODE PWM CONTROLLER

SG1844/SG1845 Series
THE INFINITE POWER OF INNOVATION
CURRENT MODE PWM CONTROLLER
PRODUCTION DATA SHEET
DESCRIPTION
The SG1844/45 family of control ICs and start-up current of less than 1mA. The
provides all the necessary features to totem-pole output is optimized to drive the
implement off-line fixed frequency, current- gate of a power MOSFET. The output is low
mode switching power supplies with a in the off state to provide direct interface to
minimum number of external components. an N-channel device. Both operate up to a
Current-mode architecture demonstrates maximum duty cycle range of zero to <50%
improved line regulation, improved load due to an internal toggle flip-flop which
regulation, pulse-by pulse current limiting blanks the output off every other clock
and inherent protection of the power supply cycle. The SG1844/45 is specified for
output switch. The bandgap reference is operation over the full military ambient
trimmed to ±1% over temperature. Oscillator temperature range of -55°C to 125°C. The
discharge current is trimmed to less than SG2844/45 is specified for the industrial
±10%. The SG1844/45 has undervoltage range of -25°C to 85°C, and the SG3844/45
lockout, current-limiting circuitry
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 HIGHLIGHT
R_ST
KEY FEATURES
„ 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
(SG1844 only)
„ DOUBLE PULSE
SUPPRESSION
„ HIGH-CURRENT TOTEM-POLE
OUTPUT
„ INTERNALLY TRIMMED
BANDGAP REFERENCE
„ 500kHz OPERATION
„ UNDERVOLTAGE LOCKOUT
SG1844 - 16 volts SG1845 - 8.4
volts
„ LOW SHOOT-THROUGH
CURRENT <75mA OVER
TEMPERATURE
AC
INPUT
I_ST
V_CC
SG3844
HIGH RELIABILITY
FEATURES
„ AVAILABLE TO MIL-STD-883B
„ LINFINITY LEVEL "S"
PROCESSING AVAILABLE
T_A (°C)
Plastic DIP
Plastic DIP
M _8-Pin
N _14-Pin
RoHS Compliant / Pb-free
Transition DC: 0503
0 to 70
SG3844M
SG3845M
SG3844N
SG3845N
-25 to 85
SG2844M
SG2845M
SG28424N
SG2845N
-55 to
125
MIL-
STD/883
DESC
PACKAGE ORDER INFO
Plastic SOIC
Plastic SOIC
Ceramic Dip
DM _8-Pin
D _14-Pin
Y _8-Pin
RoHS Compliant / Pb-free
Transition DC:0440
SG3844DM
SG3845DM
SG3844D
SG3845D
SG3844Y
SG3845Y
SG2844DM
SG2845DM
SG2842D
SG2845D
SG2844Y
SG2845Y
SG1844Y
SG1845Y
SG1842Y/883B
SG1845Y/883B
SG1844Y/DESC
Ceramic DIP
J _14-Pin
SG3844J
SG3845J
SG2844J
SG2845J
SG1844J
SG1845J
SG1844J/883B
SG1845J/883
SG1844J/DESC
Cer Flatpack
Ceramic LCC
F _10-Pin
L _20-Pin
SG1844L
SG1845L
SG1844L/883B
SG1845L/883B
SG1844F/DESC SG1844L/DESC
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LXSG3844N-TR)
Copyright © 2000
Rev. 1.6c,2006-02-02
LINFINITY MICROELECTRONICS INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: [phone]
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