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.