HCPL-788J-500E

The HCPL-788J isolation amplifier is designed for current sensing in electronic motor drives. In a typical implementation, motor currents flow through an external resistor and the resulting analog voltage drop is sensed by the HCPL-788J. A larger analog output voltage is created on the other side of the HCPL-788J’s optical isolation barrier. The output voltage is proportional to the motor current and can be connected directly to a single-supply A/D converter. A digital over-range output (FAULT) and an analog rectified output (ABSVAL) are also provided. The wire OR-able over-range output (FAULT) is useful for quick detection of short circuit conditions on any of the motor phases. The wire-OR-able rectified output (ABSVAL), simplifies measurement of motor load since it performs polyphase rectification. Since the common-mode voltage swings several hundred volts in tens of nanoseconds in modern electronic motor drives, the HCPL-788J was designed to ignore very high commonmode transient slew rates (10 kV/μs).

Applications

• Motor phase and rail current sensing
• Power inverter current and voltage sensing
• Industrial process control
• Data acquisition systems
• General purpose current and voltage sensing
• Traditional current transducer replacements

Key features

• Output Voltage Directly Compatible with A/D Converters (0 V to V_REF)
• Fast (3 μs) Short Circuit Detection with Transient Fault Rejection
• Absolute Value Signal Output for Overload Detection
• 1 μV/°C Offset Change vs. Temperature
• SO-16 Package
• -40 °C to +85 °C Operating Temperature Range
• 25 kV/μs Isolation Transient Immunity
• Regulatory Approvals: UL, CSA, IEC/EN/DIN EN 60747 - 5 - 5 (1414 V_peak Working Voltage)