Ultra-low-power digital isolator for power and thermal constrained system designs

27-11-2019 | Texas Instruments | Power

Texas Instruments ISO7021 Ultra-Low Power Multi-Channel Digital Isolator can be used to isolate CMOS or LVCMOS digital I/Os. Each isolation channel possesses a logic input and output buffer separated by a double capacitive silicon dioxide insulation barrier. Innovative edge-based architecture coupled with an ON-OFF keying modulation scheme enables these isolators to use very-low power while satisfying a 3000VRMS isolation rating per UL1577. The per-channel dynamic current consumption of the device is under 120µA/Mbps. The per-channel static current consumption is 4.8µA at 3.3V, providing for the use of the device in both power and thermal constrained system designs.

The device can work as low as 1.71V, as high as 5.5V, and is fully functional with varying supply voltages on each side of the isolation barrier. The two-channel isolator arrives in a narrow body 8-SOIC package with one forward and one reverse-direction channel in an 8-SOIC package. The device provides default output high and low options. If the input power or signal is lost, the default output is high for the device without the suffix F and low for the ISO7021F device with the F suffix.

Typical applications include 4mA to 20mA loop-powered field transmitters; factory automation, process automation; low-power GPIO and UART isolation.

By Natasha Shek