+IN

-IN

V

+

RS

V

-

RG = 2*RIN

VOUT

LMP8640

RIN

RIN

IS

+

-

L

o

a

d

ADC

VA

G

G = 10 V/V in 20 V/V gain option

G = 25 V/V in 50 V/V gain option

G = 50 V/V in 100 V/V gain option

VSENSE (mV)

13.0

12.0

11.0

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

0

100

200

300

400

500

600

GAIN 20V/V

GAIN 50V/V

GAIN 100V/V

VS=12V, VCM =12V

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LMP8640, LMP8640-Q1, LMP8640HV

SNOSB28G – AUGUST 2010 – REVISED NOVEMBER 2014

LMP8640/-Q1/HV Precision High Voltage Current Sense Amplifiers

1 Features

3 Description

The LMP8640, LMP8640-Q1 and the LMP8640HV

1

•

Typical Values, TA = 25°C

are precision current sense amplifiers that detect

•

High Common-Mode Voltage Range

small differential voltages across a sense resistor in

–

LMP8640: -2 V to 42 V

the presence of high input common mode voltages

with a supply voltage range from 2.7 V to 12 V.

–

LMP8640-Q1: -2 V to 42 V, AEC-Q100

–

LMP8640HV: -2 V to 76 V

The LMP8640 and LMP8640-Q1 accept input signals

with common mode voltage range from -2 V to 42 V,

•

Supply Voltage Range: 2.7 V to 12 V

while the LMP8640HV accepts input signal with

•

Gain Options: 20 V/V; 50 V/V; 100 V/V

common mode voltage range from -2 V to 76 V. The

•

Max Gain Error: 0.25%

LMP8640 and LMP8640HV have fixed gain for

applications that demand accuracy over temperature.

•

Low Offset Voltage: 900 µV

The LMP8640 and LMP8640HV come out with three

•

Input Bias Current: 13 µA

different fixed gains 20 V/V, 50 V/V, 100 V/V ensuring

•

PSRR: 85 dB

a gain accuracy as low as 0.25%. The output is

•

CMRR (2.1V to 42V): 103 dB

buffered in order to provide low output impedance.

This high side current sense amplifier is ideal for

•

Temperature Range: -40°C to 125°C

sensing and monitoring currents in DC or battery

•

6-Pin Thin SOT-23 Package

powered

systems,

excellent

AC

and

DC

specifications over temperature, and keeps errors in

2 Applications

the current sense loop to a minimum. The LMP8640

and LMP8640HV are ideal choice for industrial and

•

High-Side Current Sense

consumer applications, while the LMP8640-Q1 is an

•

Vehicle Current Measurement

AEC-Q100 grade 1 qualified version of the LMP8640

•

Motor Controls

for

automotive

applications.

The

LMP8640-x

is

available in SOT-23-6 package.

•

Battery Monitoring

•

Remote Sensing

Device Information(1)

•

Power Management

PART NUMBER

PACKAGE

BODY SIZE (NOM)

LMP8640

LMP8640-Q1

SOT23 (6)

2.9 mm x 1.6 mm

LMP8640HV

(1)

For all available packages, see the orderable addendum at

the end of the datasheet.

Simplified Schematic

Output Voltage vs Input Voltage

1

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.