Isolation Amplifier

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The HCPL-7800 isolation amplifier family was designed for current sensing and voltage sensing in electronic motor drives. In a typical applications, motor currents flow through an external resistor and the resulting analog voltage drop is sensed by the HCPL-7800. The HCPL-7800 isolation amplifier family is based on Broadcom's optocoupler and optoelectronic technology.

A differential output voltage is created on the other side of the HCPL-7800 optical isolation barrier. This differential output voltage is proportional to the motor current and can be converted to a single-ended signal by using an op-amp. Since common-mode voltage swings of several hundred volts in tens of nanoseconds are common in modern switching inverter motor drives, the HCPL-7800 was designed to ignore very high common-mode transient slew rates (of at least 10 kV/ms).

The high CMR capability of the HCPL-7800 isolation amplifier provides the precision and stability needed to accurately monitor motor current in high noise motor control environments, providing for smoother control (less "torque ripple") in various types of motor control applications.

The current sensor can also be used for general analog signal isolation applications requiring high accuracy, stability, and linearity under similarly severe noise conditions. For general applications, we recommend the HCPL-7800 (gain tolerance of /- 3%). The HCPL-7800 utilizes sigma delta (S-D) analog-to-digital converter technology, chopper stabilized amplifiers, and a fully differential circuit topology.

Together, these features deliver unequaled isolation-mode noise rejection, as well as excellent offset and gain accuracy and stability over time and temperature. This performance is delivered in a compact, auto-insertable, industry standard 8-pin DIP package that meets worldwide regulatory safety standards. (A gull-wing surface mount option #300 is also available).


  • 15 kV/us Common-Mode Rejection at VCM = 1000 V
  • Compact, Auto-Insertable Standard 8-pin DIP Package
  • 0.00025 V/V/ degrees C Gain Drift vs. Temperature
  • 0.3 mV Input Offset Voltage
  • 100 kHz Bandwidth
  • 0.004% Nonlinearity
  • Worldwide Safety Approval:
    UL 1577 (3750 Vrms/1 min.), CSA and IEC/EN/DIN EN 60747-5-2
  • Advanced Sigma-Delta (S-D) A/D Converter Technology
  • Fully Differential Circuit Topology
  • Options available are:
    300 = Surface Mount Option
    500 = Tape and Reel Packaging Option


  • Motor Phase and Rail Current Sensing
  • DC Bus Voltage sensing
  • Inverter Current Sensing
  • Switched Mode Power Supply Signal Isolation
  • General Purpose Current Sensing and Monitoring
  • General Purpose Analog Signal Isolation
  • Traditional Hall Effect Current Sensor Replacement

Lifecycle Status


Substance Compliance

  • RoHS
    Pb & Pb-free options available
Specification Value
Lifecycle Active
Distrib. Inventory Yes
RoHS6 Compliant Pb & Pb-free options available
Product Type Miniature Isolation Amplifier
Package 300mil DIP-8
Operating Temperature Deg C -40 to +85
Gain Error at 25 Deg C (%) Max ±3
VDD2 (V) 4.5 - 5.5
CMR (min.) (V/µs) 15000.0
Vcm (V) 1000.0
UL Insulation Rating Viso (VRMS) 3750.0
IEC Maximum Working Insulation Voltage Viorm (VPEAK) 891.0
IEC Highest Allowable Overvoltage Viotm (VPEAK) 6000
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Options Data Sheet6 i
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