1

LTC1042

1042fa

■

Micropower 1.5µW (1 Sample/Second)

■

Wide Supply Range — 2.8V to 16V

■

High Accuracy

Center Error ±1mV Max

Width Error ±0.15% Max

■

Wide Input Voltage Range

■

TTL Outputs with 5V Supply

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Two Independent Ground-Referred Control Inputs

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Small Size 8-Pin MiniDIP

The LTC

manufactured using Linear Technology’s enhanced

LTCMOS

voltage inputs, CENTER and WIDTH/2, define the middle

and width of the comparison window. Whenever the input

output is high. The ABOVE WINDOW output is high

and CENTER, the ABOVE WINDOW output becomes

Sampling techniques provide high impedance voltage

inputs that can common mode to both supply rails

non-interaction. Also the device is effectively “chopper

stabilized,” giving it extremely high accuracy over

all conditions of temperature, power supply and input

voltage range.

Another benefit of the sampling techniques used to design

the LTC1042 is the extremely low power consumption.

When the device is strobed, it internally turns on the power

to the comparators, samples the inputs, stores the outputs

in CMOS latches and then turns off power to the compara-

tors. This all happens in about 80µs. Average power can be

made small, almost arbitrarily, by lowering the strobe rate.

The device can be self-strobed using an external RC

network or strobed externally by driving the OSC pin with

a CMOS gate.

Window Comparator

■

Fault Detectors

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Go/No-Go Testing

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Microprocessor Power Supply Monitor

LTCMOS is a trademark of Linear Technology Corp.

T = YELLOW SPRINGS INSTRUMENT CO., INC. P/N 44007

ALL RESISTORS ±1% UNLESS OTHERWISE SPECIFIED

*OTHER TEMPERATURE BANDS MAY BE SELECTED BY CHOOSING APPROPRIATE VALUES FOR R1 AND R2

0.05µF

8

7

6

5

1

2

3

4

10M ±5%

TEMPERATURE

ABOVE 31°F

±1°F

“HI” =

TEMPERATURE

BETWEEN

26°F AND 31°F

±1°F

“HI” =

3V TO 16V

LTC1042 • A01

V

+

LTC1042

R2*

576Ω

R1*

7.5k

150k

150k

T

Battery-Powered Remote Freezer Alarm

Total Supply Current

vs Sampling Frequency

0.1

0.01

0.1

1

10

100

1000

10000

110

100

1000

LTC1042 • TA02

10000

FOR THIS APPLICATION

LTC1042 SUPPLY

CURRENT

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO

, LTC and LT are registered trademarks of Linear Technology Corporation.