MICROPROCESSOR MONITOR
1
2
3
4
5
6
7
8
TC1232
tPB
tF
tPBD
PB RST
VIH
VCC
VIL
tRST
+4.75V
RST
RST
+4.25V
Figure 3. Push-button Reset. The debounced PB RST input
ignores input pulses less than 1msec and is guaranteed
to recognize pulses of 20msec or greater
Figure 5. Power-Down Slew Rate
PUSH-BUTTON RESET
tST
ST
tR
+4.75V
tTD
+4.25V
tTD IS THE MAXIMUM ELAPSED TIME BETWEEN ST HIGH-TO-LOW
TRANSITIONS (ST IS ACTIVATED BY FALLING EDGES ONLY) WHICH
WILL KEEP THE WATCHDOG TIMER FROM FORCING THE RESET
OUTPUTS ACTIVE FOR A TIME OF RST. TD IS A FUNCTION OF THE
VOLTAGE AT THE TD PIN, AS TABULATED BELOW.
NOTE:
t
t
VCC
tTD
CONDITON
MIN
TYP
MAX
62.5msec
250msec
500msec
150msec
600msec
1200msec 2000msec
250msec
1000msec
TD PIN = 0V
TD PIN = OPEN
TD PIN = V
CC
Figure 4. Strobe Input
Figure 6. Power-Up Slew Rate
TELCOM SEMICONDUCTOR, INC.
5-23
TELCOM [ TELCOM SEMICONDUCTOR, INC ]
