DESCRIPTION
The Broadcom® HCPL-7840 isolation amplifier family 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-7840. A differential output voltage is created on the other side of the HCPL-7840 optical isolation barrier. Since common-mode voltage swings of several hundred volts in tens of nanoseconds are common in modern switching inverter motor drives, the HCPL-7840 was designed to ignore very high common-mode transient slew rates (of at least 10 kV/μs). The product 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-7840 (gain tolerance of ±5%). The HCPL-7840 uses sigma-delta (Σ-Δ) analog-to-digital converter technology, chopper stabilized amplifiers, and a fully differential circuit topology fabricated using the Broadcom 0.8-μm CMOS IC process.
Broadcom
