Description

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

Features

• 15 kV/µs Common-Mode Rejection at VCM = 1000 V

• Compact, Auto-Insertable Standard 8-pin DIP Package

• 0.00025 V/V/°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.)

and CSA, IEC/EN/DIN EN 60747-5-2

• Advanced Sigma-Delta (Σ−∆) A/D Converter Technology

• Fully Differential Circuit Topology

Applications

• Motor Phase and Rail Current Sensing

• Inverter Current Sensing

• Switched Mode Power Supply Signal Isolation

• General Purpose Current Sensing and Monitoring

• General Purpose Analog Signal Isolation