cat813zi-g Catalyst Semiconductor, cat813zi-g Datasheet - Page 10

• Manufacturer Part Number: cat813zi-g
• Description: ?p Supervisory Circuits
• Manufacturer: Catalyst Semiconductor

CAT705, CAT706, CAT813
APPLICATION NOTES
µP’s with Bidirectional Reset Pins
The RESET
like the 68HC11 allowing for a system reset issued by
the processor. The maximum pullup current that can
be sourced by the CAT705 & CAT706 1.5mA (and by
the CAT706 T/R/S is 800µA) allowing the processor to
pull the output low even when the CAT70x is pulling it
high.
Power Transients
Generally short duration negative-going transients of
less than 2µs on the power supply at V
will not cause a reset condition. However the lower
the voltage of the transient the shorter the required
time to cause a reset output.
usually be remedied by the proper location of bypass
capacitance on the circuit board.
Doc. No. MD-3030 Rev. A
¯¯¯¯¯¯ output can be pulled low by processors
UNREGULATED DC
Push Switch
GND
V
MR
PFI
CC
These issues can
Figure 8. RESET
CAT705
CAT706
CAT813
Figure 9. Typical Operating Circuit
RST
5V
GND
V
minimum
MR
PFI
CC
¯¯¯¯¯¯ Valid for V
WDO
RESET/RESET
WDI
PFO
CAT705
CAT706
CAT813
10
OUTPUT VALID CONDITIONS
The RESET
maintain a valid output down to a V
sink current below 0.8V a resistor can be connected
from RESET
arrangement will maintain a valid value on the RESET
output during both power up and down but will draw
current when the RESET
resistor value of about 100kΩ  s hould be adequate in
most situations to maintain a low condition valid
output down to V
WDO
RESET/RESET
WDI
PFO
¯¯¯¯¯¯ output uses a push-pull output which can
¯¯¯¯¯¯ to Ground (see Figure 8.)
100kΩ
CC
< 1.0V
RESET/RESET
CC
¯¯¯¯¯¯ output is in the high state. A
µC
equal to 1.0V.
VCC
NMI
RESET/RESET
I/O LINE
INTERRUPT
Characteristics subject to change without notice
µC
CC
© Catalyst Semiconductor, Inc.
of 1.0 volts. To
¯¯¯¯¯¯
This