The CAT853, CAT863, CAT859, and CAT869 are supervisory circuits that monitor power supplies in digital systems.
These devices generate a reset signal, which is asserted while the power supply voltage is below a preset threshold level and for at least 140 ms after the power supply level has risen above that level. Industry standard threshold levels are offered to support +3.3 V or 5.0 V systems.
The CAT859 and CAT869 feature a
push-pull output (active low) for the two pinout options.
The CAT853 and CAT863 feature an open drain RESET output (active low). Both require a pull-up resistor on the
output.
Fast transients on the power supply are ignored and the output is guaranteed to be in the correct state at VCC levels as low as 1.0 V.

• Precision monitoring of +3.3V (-5%, -10%), 5V (-10% Power Supplies)
• Active Low Reset Output
• Reset valid down to V
• = 1.0V
• 6μA power supply current
• Power supply transient immunity
• Industrial temperature range: -40°C to +85°C
• These Devices are PbFree and are RoHS Compliant
• SOT-23 Package