DS1238
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NOTES:
1. All voltages referenced to ground.
2. Measured with V
CCO
, CEO , PF, ST , RST, RST , and NMI pin open.
3. I
CCO1
is the maximum average load which the DS1238 can supply at V
CC
-.3V through the V
CCO
pin
during normal 5-volt operation.
4. I
CCO2
is the maximum average load which the DS1238 can supply through the V
CCO
pin during data
retention battery supply operation, with a maximum drop of 0.8 volts for commercial, 1.0V for
industrial.
5. With t
R
= 5 µs.
6. V
CCO
is approximately V
BAT
-0.5V at 1 µA load.
7. t
REC
is the minimum time required before CEI /CEO memory access is allowed.
8. t
CE
maximum must be met to insure data integrity on power loss.
9. All outputs except RST which is 25 µA max.
10. All outputs except RST , RVT , and NMI which is 25 µA min.
11. The
ST pin will sink +50 µA in normal operation. The OSCIN pin will sink ±5 µA in normal
operation. The OSCSEL pin will sink ±10 µA in normal operation.
12. I
BAT
is measured with V
BAT
=3.0V.
13.
ST should be active low before the watchdog is disabled (i.e., before the ST input is tristated).
