SG1548 Datasheet, PDF (1/4 Pages) Microsemi Corporation – QUAD POWER FAULT MONITOR

SG1548/SG2548/SG3548
QUAD POWER FAULT MONITOR
DESCRIPTION
The SG1548 is an integrated circuit capable of monitoring up to four
positive DC supply voltages simultaneously for overvoltage and
undervoltage fault conditions. An on-chip inverting op amp also
allows monitoring one negative DC voltage. The fault tolerance
window is accurately programmable from ±5% to ±40% using a simple
divider network on the 2.5V reference. A single external capacitor sets
the fault indication delay, eliminating false outputs due to switching
noise, logic transition current spikes, and short-term AC line interrup-
tions. An additional comparator referenced to 2.5V allows the AC line
to be monitored for undervoltage conditions or for generation of a line
clock. The comparator can also be used for programmable
undervoltage lockout in a switching power supply. Uncommitted
collector and emitter outputs permit both inverting and non-inverting
operation. External availability of the precision 2.5V reference and
open-collector logic outputs permit expansion to monitor additional
voltage using available open-collector quad comparators.
FEATURES
• Monitors four DC voltages and the AC line
• Precision 2.5V ±1% low-drift reference
• Fault tolerance adjustable from ±5% to ±40%
• ±3% trip threshold tolerance over temperature
• Separate 10mA, 40V overvoltage, undervoltage
and AC line fault outputs
• Fault delay programmable with a single capacitor
• 30mV comparator hysteresis to prevent oscilla-
tions
• On-chip inverting op amp for negative voltage
• Open-collector output logic or expandability
• Operation from 4.5V to 40V supply
HIGH RELIABILITY FEATURES - SG1548
♦ Available to MIL-STD-883
♦ Radiation data available
♦ LMI level "S" processing available
BLOCK DIAGRAM
11/91 Rev 1.2 5/97
Copyright © 1997
LINFINITY Microelectronics Inc.
11861 Western Avenue ∞ Garden Grove, CA 92841
1
[phone] ∞ FAX: [phone]