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LT1787/LT1787HV

Precision, High Side

Current Sense Amplifiers

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Input Offset Voltage: 75

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60V Supply Operation (LT1787HV)

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12-Bit Dynamic Range

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Operating Current: 60

µA

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User-Selectable External Sense Resistor

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Bidirectional High Side Current Sensing

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Unidirectional or Bidirectional Output

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Input Noise Filtering

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Available in 8-Lead SO and MSOP Packages

The LT

side current sense amplifier. The LT1787 monitors bidi-

rectional currents via the voltage across an external sense

resistor. A current or voltage output depicts the direction

and magnitude of the sense current. The LT1787 delivers

greater than a 12-bit dynamic range with ultralow 40

µV

input offset voltage compared to a typical 250mV full-

scale input voltage. A fixed gain of 8 is set by onboard

precision resistors. Input signal filtering is easily imple-

The LT1787HV operates from 2.5V to 60V total supply

voltage and the LT1787 operates from 2.5V to 36V total

supply voltage. Both versions have a PSRR in excess of

120dB. The LT1787/LT1787HV draw only 60

µA and are

available in 8-lead SO and MSOP packages.

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Battery Monitoring

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Power Monitoring

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Portable Phones

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Cellular Phones

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Portable Test/Measurement Systems

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Battery-Operated Systems

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

Input Offset Voltage vs Supply Voltage

12-Bit Dynamic Resolution Unidirectional Output into LTC

TOTAL SUPPLY VOLTAGE (V)

0

10

20

30

40

1787 TA01b

50

50

40

30

20

10

0

–10

–20

–30

–40

–50

60

18

27

36

45

LT1787HV

0.0016

Ω

1787 TA01

C1

1

µF

5V

R1

15k

C2

0.1

µF

I = 100A

2.5V TO 60V

TO

LOAD

LT1634-1.25

TO

µP

GND

LTC1286

CS

CLK

+IN

–IN

20k

–

+

DNC

APPLICATIO S

FEATURES

TYPICAL APPLICATIO

DESCRIPTIO