1 Features

• Typical Values, TA = 25°C

• High Common-Mode Voltage Range

– LMP8645 –2 V to 42 V

– LMP8645HV –2 V to 76 V

• Supply Voltage Range 2.7 V to 12 V

• Gain Configurable With a Single Resistor

• Maximum Variable Gain Accuracy (With External

Resistor) 2%

• Transconductance 200 μA/V

• Low Offset Voltage 1 mV

• Input Bias 12 μA

• PSRR 90 dB

• CMRR 95 dB

• Temperature Range −40°C to 125°C

• 6-Pin SOT Package

2 Applications

• High-Side Current Sense

• Vehicle Current Measurement

• Motor Controls

• Battery Monitoring

• Remote Sensing

• Power Management

3 Description

The LMP8645 and the LMP8645HV devices are

precision current sense amplifiers that detect small

differential voltages across a sense resistor in the

presence of high-input common-mode voltages.

Operating from a supply range of 2.7 V to 12

V, the LMP8645 accepts input signals with a

common-mode voltage range of –2 V to 42 V,

while the LMP8645HV accepts input signals with

a common-mode voltage range of –2 V to 76 V.

The LMP8645 and LMP8645HV have adjustable

gain for applications where supply current and high

common-mode voltage are the determining factors.

The gain is configured with a single resistor, providing

a high level of flexibility, as well as accuracy as

low as 2% (maximum) including the gain setting

resistor. The output is buffered to provide low output

impedance. This high-side current sense amplifier is

ideal for sensing and monitoring currents in DC or

battery-powered systems, has excellent AC and DC

specifications over temperature, and keeps errors in

the current sense loop to a minimum. The LMP8645

is an ideal choice for industrial, automotive, and

consumer applications, and is available in SOT-6

package.