Supervisory Circuits Require Only 2 µA

Two new supervisory circuits combine high accuracy with low supply current requirements. The ZXCM209 and ZXCM210 provide precision monitoring of 5V, 3.3V and 3V power supply voltages in microprocessor and digital systems. The typical 2 µA supply current is said to be more than seven times lower than competitive parts. The resultant power saving makes the ZXCM209/210 well-suited for portable and battery-powered applications.
Whenever the supply voltage falls below a preset threshold, the devices produce a reset signal. To insure a correct response to fault conditions, the reset pulse is active for a minimum period of 140 ms after supply restoration.
The devices provide a highly accurate reset threshold with a tolerance of just 1%. Parts with threshold voltages between 2.63V and 4.63V are also available. The ZXCM209 has an active-low reset output, while the ZXCM210 has an active-high reset output. For space savings, the devices are supplied in a SOT23 surface-mount package with an industry standard pinout. No external components are required. Pricing is $0.28 each/10,000.