Failsafe comparators with guaranteed start-up time

STMicroelectronics has developed two rail-to-rail, open-drain, single channel comparators with guaranteed start-up time to simplify powering up for short periods.

The TS3121 and TS3121A use a failsafe architecture allows analog sensor voltages to remain at the inputs when the supply voltage is cut, which ensures robust performance and helps simplify application firmware. The guaranteed start-up time allows frequent power cycling with extended off duration for maximum power savings.

The comparators are inspired by robots that use sensors running from a back-up battery to maintain positional awareness while the main system turns off saving power, these comparators fulfill diverse automation applications. Independent supply, I/O, and output voltage domains allow flexible level shifting for industrial controls, building automation, power tools, and smart metering.

Both the TS3121 and TS3121A are also available as automotive-qualified devices that are suited to use in applications such as powertrain and body-control modules.

The comparators operate over a wide supply-voltage range, from 1.7V to 5.5V, and feature a precision input stage that facilitates accurate threshold detection with typical propagation delay of 60ns. Both devices have typical input-offset voltage of 0.5mV, with a specified maximum offset of 2mV for the TS3121A and 6mV for the TS3121. Both tolerate ESD up to 4kV (HBM), and operate over the extended temperature range from -40°C to 125°C. The comparators are available in space-saving SC70-5 and standard SOT23-5 packages.

The TS3121 and TS3121A are available now, priced from $0.60 for orders of 1000 units and free samples of the TS3121 and TS3121A are available on the ST eStore. The comparators are included in ST’s 10-year longevity program that guarantees long-term product availability