Datasheet

DS1972
1024-Bit EEPROM i
Button
4 _______________________________________________________________________________________
Note 19: Current drawn from IO during the EEPROM programming interval. The pullup circuit on IO during the programming interval
should be such that the voltage at IO is greater than or equal to V
PUPMIN
. If V
PUP
in the system is close to V
PUPMIN
, a low-
impedance bypass of R
PUP
, which can be activated during programming, may need to be added.
Note 20: Interval begins t
REHMAX
after the trailing rising edge on IO for the last time slot of the E/S byte for a valid Copy Scratchpad
sequence. Interval ends once the device’s self-timed EEPROM programming cycle is complete and the current drawn by
the device has returned from I
PROG
to I
L
.
Note 21: Write-cycle endurance is degraded as T
A
increases.
Note 22: Not 100% production tested; guaranteed by reliability monitor sampling.
Note 23: Data retention is degraded as T
A
increases.
Note 24: Guaranteed by 100% production test at elevated temperature for a shorter time; equivalence of this production test to the
data sheet limit at operating temperature range is established by reliability testing.
Note 25: EEPROM writes can become nonfunctional after the data-retention time is exceeded. Long-term storage at elevated tem-
peratures is not recommended; the device can lose its write capability after 10 years at +125°C or 40 years at +85°C.
COMPARISON TABLE
LEGACY VALUES DS1972 VALUES
STANDARD SPEED
(μs)
OVERDRIVE SPEED
(μs)
STANDARD SPEED
(μs)
OVERDRIVE SPEED
(μs)
PARAMETER
MIN MAX MIN MAX MIN MAX MIN MAX
t
SLOT
(including t
REC
) 61 (undefined) 7 (undefined) 65* (undefined) 8* (undefined)
t
RSTL
480 (undefined) 48 80 480 640 48 80
t
PDH
15 60 2 6 15 60 2 6
t
PDL
60 240 8 24 60 240 8 24
t
W0L
60 120 6 16 60 120 6 15.5
* Intentional change; longer recovery time requirement due to modified 1-Wire front-end.
Note: Numbers in bold are not in compliance with legacy 1-Wire product standards.