Avago launches three precision isolation amplifiers for industrial motor control and renewable energy markets

SAN JOSE, USA & SINGAPORE: Avago Technologies has announced three Miniature Precision Isolation Amplifiers with increased accuracy, bandwidth and high insulation made possible by proprietary optical isolation technology.

Based on sigma-delta analog-to-digital converters and chopper stabilized amplifiers, the new isolation amplifiers feature high gain accuracy, low temperature drift, 3.3 V/5 V output supply operation and a wide -40 to +105°C operating temperature range.

These features are delivered in a stretched SO-8 package that has a footprint 30 percent smaller than the standard DIP-8 package. When mounted on a PCB, it occupies a space that is a fraction of that for a traditional Hall Effect or transformer based isolation amplifier.

The series is implemented with a fully differential circuit topology with a gain accuracy of ±0.5 percent (ACPL-C79B), ±1 percent (ACPL-C79A), and ±3 percent (ACPL-C790). Normalized gain drift is -50 ppm/°C.

With a 200 kHz bandwidth and 1.6 µs response time, the ACPL-C79x captures transients during short circuit and overload conditions. Operating from a single 5 V supply, the isolation amplifier series features an excellent nonlinearity of 0.05 percent and a SNR of 60 dB.

The ACPL-C79x high common-mode transient immunity of 15 kV/µs provides the precision and stability needed to accurately monitor current in high noise motor control environments. This ensures smoother control with less “torque ripple” in many motor control applications.