ACPL-C741

Overview

The Broadcom® ACPL-C741 is a 1-bit, second-order sigma-delta (Σ-Δ) modulator that converts an analog input signal into a high-speed data stream with galvanic isolation based on optical coupling technology. The ACPL-C741 operates from a 5V power supply with dynamic range of 86dB with an appropriate digital filter. The differential inputs of ±200 mV (full scale ±320 mV) are ideal for direct connection to shunt resistors or other low-level signal sources in applications, such as motor phase current measurement.

The analog input is continuously sampled by means of sigma-delta over-sampling using an onboard clock. The signal information is contained in the modulator data, as a density of ones with data rate of 20 MHz, and the data are encoded and transmitted across the isolation boundary where they are recovered and decoded into high-speed data stream of digital ones and zeros. The original signal information can be reconstructed with a digital filter. The serial interface for data and clock has a wide supply range of 3V to 5.5V.

Combined with superior optical-coupling technology, the modulator delivers high noise margins and excellent immunity against isolation-mode transients. With 0.5-mm minimum distance through insulation (DTI), the ACPL-C741 provides reliable reinforced insulation and high working insulation voltage, which is suitable for fail-safe designs. This outstanding isolation performance is superior to alternatives, including devices based on capacitive- or magnetic-coupling with DTI in micro-meter range. Offered in a Stretched SO-8 (SSO-8) package, the isolated ADC delivers the reliability, small size, superior isolation, and over-temperature performance that motor drive designers need to accurately measure current at a much lower price compared to traditional current transducers.

Features

• Superior optical isolation and insulation
• 20-MHz internal clock
• 1-bit, second-order sigma-delta modulator
• 16 bits resolution no missing codes (12 bits ENOB)
• 86 dB SNR
• 1 μV/°C maximum offset drift
• ±1% gain error
• ±200 mV linear range with single 5V supply (±320 mV full scale)
• 3V to 5.5V wide supply range for digital interface
• –40°C to +110°C operating temperature range
• SSO-8 package
• 25-kV/μs common-mode transient immunity
• Safety and regulatory approval:
  • IEC/EN/DIN EN 60747-5-5: 1414 Vpeak working insulation voltage
  • UL 1577: 5000 Vrms/1min isolation voltage
  • CAN/CSA-C22.2 No. 62368-1

Applications

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

Lifecycle Status

Active

Substance Compliance

RoHS6

Y

Specifications

Documentation