Suited for industrial power applications, the device transfers data between two isolated domains at up to 100Mbit/s
A new series of high-performance ICs, the STISO621 dual-channel digital isolator by STMicroelectronics is suitable for industrial applications in power supplies, motor drives, metres, inverters, battery monitors, appliances, fieldbus isolators, size-critical multichannel isolation adaptors, general isolation throughout industrial-automation systems and general optocoupler replacement.
The STISO621 can transfer data between two isolated domains at up to 100Mbit/s with pulse distortion below 3ns, leveraging ST’s 6kV thick-oxide galvanic-isolation technology. Two independent unidirectional channels allow the device to function as a UART interface for handling data in both directions. Schmitt-trigger inputs to each channel ensure high noise immunity.
The wide supply voltages to the two mutually galvanically isolated sides of the STISO621 are independent of each other, allowing level translation between 3.3V and 5.5V circuitry. Typical common-mode transient immunity (CMTI) of 65kV/µs protects the low-voltage side against high switching transients in harsh environments.
The device design meets VDE0884-10 and UL 1577 specifications for high-voltage applications.
The EVALSTISO62XV1 evaluation board accelerates design completion in multiple applications. The EVALSTPM-3PHISO reference design is designed for three-phase isolated metering-systems use cases. It combines the STISO621 to separate high voltage domains with ST’s high-accuracy STPMS2 metering front-end IC and specific firmware running on an STM32 microcontroller for computing three-phase metrology and power-quality data.
With a maximum working isolation voltage (VIOWM) of 1200Vpeak and high impulse-withstand voltage (VIOTM), galvanic insulation integrity is maintained over time and during any system faults. Two package variants are offered: the STIS621 in SO8 narrow-body (4mm creepage and clearance, VIOTM of 4800V) and STISO621W in SO8 wide-body (8mm creepage and clearance, VIOTM of 6000V). The temperature range is from -40°C to 125°C for high-performance.
The STISO621 and STISO621W are both in production. The EVALSTISO62XV1 and the EVALSTPM-3PHISO are also available from ST and authorised distributors.