DS1233 Datasheet, PDF (2/5 Pages) Dallas Semiconductor – 5V EconoReset

OPERATION - PUSHBUTTON RESET
DS1233
The DS1233 provides for a pushbutton switch to be connected to the RST output pin. When the DS1233
is not in a reset cycle, it continuously monitors the RST signal for a low going edge. If an edge is
detected, the DS1233 will debounce the switch by pulling the RST line low. After the internal timer has
expired, the DS1233 will continue to monitor the RST line. If the line is still low, the DS1233 will
continue to monitor the line looking for a rising edge. Upon detecting a release, the DS1233 will force the
RST line low and hold it low for 350 ms.
NOTE:
For proper operation with an external pushbutton, a capacitor between 100 pF and 0.01 µF must be
connected between RST and ground. In applications where additional reset current is required, a
minimum capacitance of 500 pF should be used, along with a parallel external pull-up resistor of 1
kΩ=minimum.
BLOCK DIAGRAM Figure 1
APPLICATION EXAMPLE Figure 2
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