FM809 Datasheet, PDF (1/8 Pages) Fairchild Semiconductor – 3-Pin μC Supervisor Circuits

October 2002
FM809/810
3-Pin µC Supervisor Circuits
General Description
The FM809/810 are supervisor circuits that monitor power
supply or other system voltages and issue reset pulse whenever
the voltage being monitored is out of tolerance. Once asserted,
the reset pulse is guaranteed to be valid for a minimum of
140ms (256ms typical). FM809xx offers active low push-pull
type of reset while FM810xx offers active high push-pull type.
Several threshold voltages are offered to accommodate 5.0V,
3.3V, 3.0V and 2.7V system voltages.
The low supply current (typically 2 µA)recommends FM809/810
devices for portable designs or wherever power saving is
primary.
These devices are offered in space saving 3-pin SOT23 and
SC70 packages.
Features
I V_TH voltages of 4.63V, 4.38V, 4.00V, 3.08V, 2.93V and 2.63V
I RESET (FM809) or RESET (FM810) output
I 140ms power-on RESET delay (minimum)
I RESET operation guaranteed to 1.0V
I Supply current only 2µA
I No external components
I Operating Range
– -40°C to +105°C (SOT23)
– -40°C to +85°C (SC70)
I SOT23-3 and SC70-3 packages
Applications
I Microcontrollers and Microprocessors
I Appliances
I Power-Supply Monitoring
I Portable Equipment
I Automotive Systems
Typical Operating Circuit
VCC
FM809
RESET
GND
Connection Diagram
VCC
µC
RESET
I/P
GND
GND 1
RESET (809) or
RESET (810) ²
3 V_CC
FM809/810
SOT23-3 & SC70-3Packages
©2002 Fairchild Semiconductor Corporation
1
FM809/810 Rev. F
www.fairchildsemi.com