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

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

!

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

3

IN+

1

OUT

2

4

IN-