© 2002 Microchip Technology Inc.

DS21342B-page 5

TC1031

3.0

DETAILED DESCRIPTION

The TC1031 is one of a series of very low-power, linear

building block products targeted at low-voltage, single-

supply applications. Minimum operating voltage for the

device is 1.8V, and typical supply current is only 6

µA

(fully enabled). It combines one comparator and a

voltage reference in a single package. The comparator

and reference outputs are in a high-impedance state

during shutdown.

3.1

Comparator

The TC1031 contains one comparator with program-

mable hysteresis. The range of the inputs extends

beyond both supply voltages by 200mV. The compara-

tor outputs will swing to within several millivolts of the

supplies depending on the load current being driven.

The comparator exhibits a propagation delay and

supply current which is largely independent of supply

voltage. The low input bias current and offset voltage

make

it

suitable

for

high

impedance

precision

applications.

The comparator is disabled during shutdown and has

high-impedance output.

3.2

Voltage Reference

A 2.0% tolerance, internally biased, 1.20V bandgap

voltage reference is included in the TC1031. It has a

push-pull output capable of sourcing and sinking at

least 50

µA. The voltage reference is disabled during

shutdown, with a high-impedance output.

3.3

Shutdown Input

reference and reduces the supply current to less than

0.1

µA. The SHDN input cannot be allowed to float;

high impedance state when the TC1031 is disabled.

The comparator’s inputs and output can be driven from

rail-to-rail by an external voltage when the TC1031 is

disabled. No latchup will occur when the device is

3.4

Programmable Hysteresis

Hysteresis is added to the comparators by connecting

where:

and is symmetrical around the normal (without

hysterersis)

threshold

of

the

comparator.

The

pins is 80mV, giving a maximum hysteresis of 160mV.

FIGURE 3-1:

TC1031 PROGRAMMABLE HYSTERESIS

4.0

TYPICAL APPLICATIONS

The TC1031 lends itself to a wide variety of

applications, particularly in battery-powered systems. It

typically finds application in power management,

processor supervisory and interface circuitry.

HYST

TC1031

6

5

1

R1

R2

R1 =

R2 =

)

2