DS1236
19 of 19
CAPACITANCE (t
A
=25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Input Capacitance C
IN
5 pF
Output Capacitance C
OUT
7 pF
NOTES:
1. All voltages referenced to ground. A 0.1 μF capacitor is recommended between V
CC
and GND.
2. Measured with V
CCO
, CEO , PF, ST , PBRST , RST, RST , and NMI pin open. I
BAT
specified at 25°C.
3. I
CCO1
is the maximum average load which the DS1236 can supply at V
CC
-0.3V through the V
CCO
pin
during normal 5-volt operation.
4. I
CCO2
is the maximum average load which the DS1236 can supply through the V
CCO
pin during data
retention battery supply operation, with a maximum drop of 0.8 volts.
5. With t
R
= 5 μs.
6. V
CCO
is approximately V
BAT
-0.5V at 1 μA load.
7. Sleep mode is not invoked.
8. Sleep mode is invoked.
9. t
REC
is the minimum time required before CEI /CEO memory access is allowed.
10. t
CE
maximum must be met to ensure data integrity on power loss.
11. IN input is less than V
TP
but V
CC
greater than V
CCTP
.
12. All outputs except RST which is 25 μA minimum.
13. All outputs except RST and NMI which is 25 μA maximum.
14. Pulse width of NMI requires that the IN pin remain below V
TP
. If the IN pin returns to a level above
V
TP
for a period longer than t
IPD
and before the t
NMI
period has elapsed, the NMI pin will immediately
return to a high.
15. IN pin greater than V
TP
when V
CC
supply rises to V
BAT
. Example: IN tied to GND.
16. IN pin less than V
TP
when V
CC
supply rises to V
BAT
.
17. CEI low.
18. The WC/SC pin contains an internal latch which drives back on to the pin. This latch requires ±200
μamps to switch states. The
ST pin will sink ±50 μamps in normal operation and ±1 μamp in the
sleep mode.
19. ST should be active low before the watchdog is disabled (i.e., before the ST input is tristated).
