High accuracy optically isolated delta-sigma modulator

News | July 30, 2020

By Ally Winning

The RV1S9353A provides higher accuracy than other 10MHz clock output optically isolated devices. The device features a precision analog-to-digital converter with ENOB of 13.8 bits (typ) to convert the analog voltage input into a digital output one-bit data stream across the isolation barrier. It can connect directly to an RZ/T MPU and RX72M MCU, or other MPUs, MCUs, SoCs and FPGAs with a digital filter. The RV1S9353A is intended for use in robotic arm controllers, AC servo controllers and NC servo controllers used in smart factory equipment.

The device offers best-in-class precision sensing features, with lower offset voltage drift, higher SNR, lower reference voltage drift vs. temperature and higher input resistance. The modulator’s low offset voltage drift eases offset correction and the 5kV rms isolation and 8mm creepage distance makes the device ideal for small 200V and 400V motor drive equipment.

The RV1S9353A has 500kΩ typical input resistance, to allow it to be used for both current sensing and voltage monitoring. The ΔΣ modulator’s digital output and connected digital filter takes away the need for complex multi-component designs using an analog isolation amplifier with analog filter and other components.

“The RV1S9353A ΔΣ modulator gives our customers the absolute highest accuracy and control needed to modernize today’s smart factories,” said Chris Stephens, Vice President of Communications & Motor Control, Industrial and Communications Business Division at Renesas. “Its higher input resistance and ability to provide both current sensing and voltage monitoring simplifies design and saves costs while meeting the UL, CSA and VDE safety standards.”

Key Features of the RV1S9353A ΔΣ Modulator: