Zetex Introduces New ZXCM209 and ZXCM210 Supervisory Circuits
Zetex (Commack, NY) has introduced two new supervisory circuits, the ZXCM209 and ZXCM210. These circuits are designed to provide precision monitoring of 5V, 3.3V and 3V power supply voltages in microprocessor and digital systems.
Whenever the supply voltage falls below a preset threshold, the devices produce a reset signal. To help ensure a correct response to fault conditions, the reset pulse is active for a minimum period of 140ms after a supply restoration. Zetex claims that the devices provide a highly accurate reset threshold with a tolerance of one percent. Parts with threshold voltages between 2.63V and 4.63V are also available.
The ZXCM209 provides an active-low reset output, while the ZXCM210 has an active-high reset output. The built-in hysteresis of the reset comparator is designed to prevent erratic operation and to be immune to supply transients.
The new circuits are supplied in SOT-23 surface-mount packages with an industry-standard pin-out. No external components are required. The circuits are available for $0.28 each in 10,000-piece quantities. Delivery of small quantities from stock to production volumes takes 10 to 12 weeks.
