austriamicrosystems
AS1976, AS1977
Ultra-Low Current, 1.8V Comparators
Product Brief
© 1997-2006, austriamicrosystems AG, 8141 Unterpremstaetten, Austria-Europe. All Rights Reserved.
www.austriamicrosystems.com Revision 0.21 1 - 2
1 General Description
The AS1976/AS1977 are very low-current comparators
that can operate beyond the rail voltages and are guar-
anteed to operate down to 1.8V
Low input bias current, current-limiting output circuitry,
and ultra-small packaging make these comparators
ideal for low-power 2-cell applications including power-
management and power-monitoring systems.
The comparators are available as the standard products
listed in Table 1.
The AS1976 push/pull output can sink or source current.
The AS1977 open-drain output can be pulled beyond
VCC to a maximum of 3.6V > VEE. This open-drain
model is ideal for use as a logic-level translator or bipo-
lar-to-unipolar converter.
Large internal output drivers provide rail-to-rail output
swings with loads up to 8mA. Both devices feature built-
in battery power-management and power-monitoring cir-
cuitry.
The AS1976/AS1977 are available in a 5-pin SOT23
package.
Figure 1. Block Diagram
2 Key Features
! CMOS Push/Pull Output Sinks and Sources 8mA
(AS1976)
! CMOS Open-Drain Output Voltage Extends Beyond
VCC (AS1977)
! Ultra-Low Supply Current: 200nA
! Internal Hysteresis: 3mV
! Guaranteed to Operate Down to +1.8V
! Input Voltage Range Operates 200mV Beyond the
Rails
! Crowbar Current-Free Switching
! No Phase Reversal for Overdriven Inputs
! 5-pin SOT23 Package
3 Applications
The devices are ideal for battery monitoring/manage-
ment, mobile communication devices, laptops and
PDAs, ultra-low-power systems, threshold detectors/dis-
criminators, telemetry and remote systems, medical
instruments, or any other space-limited application with
low power-consumption requirements.
Table 1. Standard Products
Model Output Type Current
AS1976 Push/Pull 200nA
AS1977 Open-Drain 200nA
AS1976/
AS1977
–
+
5
VCC
3
IN+ 1
OUT
2
VEE
4
IN-