Renesas has brought out an optically isolated delta-sigma (ΔΣ) modulator which claims to deliver the industry’s highest accuracy compared to other 10MHz clock output optically isolated devices.

It includes a precision ADC with ENOB of 13.8 bits (typ) for converting an analogue voltage input into a digital output one-bit data stream across the isolation barrier.

The RV1S9353A connects directly to an RZ/T MPU and RX72M MCU, or other MPUs, MCUs, SoCs and FPGAs with a digital filter.

The chip is used in robotic arm controllers, as well as AC servo controllers and NC servo controllers employed in a range of smart factory equipment.

The trend toward improving control accuracy for industrial instruments is driving the demand for high-accuracy optical isolation.

Thev device is claimed to meet this need with best-in-class precision sensing features, including lower offset voltage drift, higher signal-to-noise ratio (SNR), lower reference voltage drift vs. temperature, and higher input resistance.

The modulator’s low offset voltage drift simplifies offset correction and its 5kV rms isolation and 8mm creepage distance is suitable for compact 200V and 400V motor drive equipment. OEMs want to standardize their designs during development and design certification.

The RV1S9353A addresses this requirement with 500kΩ typical input resistance making it capable of both current sensing and voltage monitoring for easier design.

The ΔΣ modulator’s digital output and connected digital filter removes the need for complex multi-component designs that use a traditional analogue isolation amplifier with analogue filter and several other components.

Key Features:

Input offset voltage drift vs temperature (max) 2.5µV/°C SNR (typ) 85dB

Reference voltage (max) gain error ±0.5%

Reference voltage drift vs. temperature (typ) 30ppm/°C High input resistance (typ.) 500kΩ High common mode transient immunity (typ) 25kV/us

Operating ambient temperature (max) -40°C to 110°C

Supplied in 8-pin SDIP with 1.27mm pin pitch

The RV1S9353A ΔΣ modulator joins Renesas’ family of optoelectronic products, including photocouplers with IC output and high-speed communication up to 15Mbps, as well as general-purpose transistor output devices featuring high isolation voltage, high temperature operation and compliance with various international safety standards.

The motor driving photocouplers (IPM drive and IGBT drive) feature high isolation voltage, high temperature operation, high output current, and high-speed switching.

Available now from Renesas’ worldwide distributors, priced at $2.41 in 1,000-unit quantities.