SNOSB28H August   2010  – October 2026 LMP8640 , LMP8640HV

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics 2.7V
    6. 6.6 Electrical Characteristics 5 V
    7. 6.7 Electrical Characteristics 12V
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Selection of Sense Resistor
        1. 7.3.1.1 Resistor Power Rating and Thermal Issues
        2. 7.3.1.2 Using PCB Trace as a Sense Resistor
      2. 7.3.2 Sense Line Inputs
      3. 7.3.3 Effects of Series Resistance on Sense Lines
    4. 7.4 Device Functional Modes
      1. 7.4.1 Bias Current at Low Common Mode Voltage
      2. 7.4.2 Applying Input Voltage With No Supply Voltage
      3. 7.4.3 Driving an ADC
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Design Procedure
        1. 8.2.2.1 First Step – LMP8640 or LMP8640HV Selection
        2. 8.2.2.2 Second Step – Gain Option Selection
        3. 8.2.2.3 Third Step – Shunt Resistor Selection
      3. 8.2.3 Application Curve
    3. 8.3 What to Do and What Not to Do
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

3 Description

The LMP8640 and the LMP8640HV are precision current sense amplifiers that detect small differential voltages across a sense resistor in the presence of high input common mode voltages with a supply voltage range from 2.7V to 12V.

The LMP8640 accepts input signals with common mode voltage range from -2V to 42V, while the LMP8640HV accepts input signal with common mode voltage range from -2V to 76V. The LMP8640 and LMP8640HV have fixed gain for applications that demand accuracy over temperature. The LMP8640 and LMP8640HV come out with three different fixed gains 20V/V, 50V/V, 100V/V providing a gain error as low as 0.25%. 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, excellent AC and DC specifications over temperature, and keeps errors in the current sense loop to a minimum. The LMP8640 and LMP8640HV are designed for industrial and consumer applications. The LMP8640x is available in SOT-23-6 package.

Package Information
PART NUMBER(1)PACKAGEPACKAGE SIZE(2)
LMP8640DDC (SOT23, 6)2.9mm x 2.8mm
LMP8640HV
(1) For all available packages, see the orderable addendum at the end of the data sheet.
(2) The package size (length × width) is a nominal value and includes pins, where applicable.
LMP8640 LMP8640HV Output Voltage vs. Input Voltage Output Voltage vs. Input Voltage