Broadcom ACPL-C797x Sigma-Delta Modulators

Broadcom ACPL-C797x Sigma-Delta Modulators are 1-bit, second-order modulators that convert an analog input signal into a high-speed data stream with galvanic isolation. These modulators operate at 3V to 5.5V wide supply range to provide a serial interface for data and clock. The ACPL-C797x modulators combined with optical coupling technology, offer high noise margins and excellent immunity against isolation-mode transients. The modulator data and on-chip sampling clock are encoded and transmitted across the isolation boundary to recover and decode into separate high-speed clock and data channels. The ACPL-C797x modulators feature ±200mV (full-scale ±320mV) differential inputs. These modulators are ideal for low-level signal sources in applications such as motor phase current measurements.


  • Superior optical isolation and insulation
  • 10MHz internal clock
  • 1-bit second-order sigma-delta modulator
  • 16-bits resolution with no missing codes (12-bits ENOB)
  • 3.5µV/°C maximum offset drift
  • ±1% gain error
  • ±200mV linear range with single 5V supply
  • 3V to 5.5V wide supply range for digital interface
  • 25kV/µs common-mode transient immunity
  • Compact, surface mount SSO-8 package


  • 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

Functional Block Diagram

Block Diagram - Broadcom ACPL-C797x Sigma-Delta Modulators

Pin Description

Broadcom ACPL-C797x Sigma-Delta Modulators
Published: 2020-04-13 | Updated: 2022-03-10