Rainbow Electronics DS1972 - Manual (Page 2)

DS1972: 1024-Bit EEPROM iButton
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ABSOLUTE MAXIMUM RATINGS
I/O Voltage to GND -0.5V, +6V
I/O Sink Current 20mA
Operating Temperature Range -40°C to +85°C
Junction Temperature +150°C
Storage Temperature Range -40°C to +85°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is
not implied. Exposure to the absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(T
A
= -40°C to +85°C; see Note 1.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
I/O PIN GENERAL DATA
1-Wire Pullup Voltage V
PUP
(Notes 2) 2.8 5.25 V
1-Wire Pullup Resistance R
PUP
(Notes 2, 3) 0.3 2.2 k W
Input Capacitance C
IO
(Notes 4, 5) 1000 pF
Input Load Current I
L
I/O pin at V
PUP
0.05 6.7 µA
High-to-Low Switching
Threshold
V
TL
(Notes 5, 6, 7) 0.46 4.4 V
Input Low Voltage V
IL
(Notes 2, 8) 0.3 V
Low-to-High Switching
Threshold
V
TH
(Notes 5, 6, 9) 1.0 4.9 V
Switching Hysteresis V
HY
(Notes 5, 6, 10) 0.21 1.70 V
Output Low Voltage V
OL
At 4mA (Note 11) 0.4 V
Standard speed, R
PUP
= 2.2k W 5
Overdrive speed, R
PUP
= 2.2k W 2 Recovery Time
(Notes 2,12)
t
REC
Overdrive speed, directly prior to Reset
Pulse; R
PUP
= 2.2k W
5
µs
Standard speed 0.5 5.0 Rising-Edge Hold-off Time
(Notes 5, 13)
t
REH Overdrive speed Not applicable (0)
µs
Standard speed 65 Timeslot Duration
(Note 2, 14)
t
SLOT Overdrive speed 8
µs
I/O PIN, 1-WIRE RESET, PRESENCE DETECT CYCLE
Standard speed 480 640
Reset Low Time (Note 2) t
RSTL Overdrive speed 48 80
µs
Standard speed 15 60 Presence Detect High
Time
t
PDH Overdrive speed 2 6
µs
Standard speed 60 240 Presence Detect Low
Time
t
PDL Overdrive speed 8 24
µs
Standard speed 60 75 Presence Detect Sample
Time (Notes 2, 15)
t
MSP
Overdrive speed 6 10
µs
I/O PIN, 1-Wire WRITE
Standard speed 60 120
Overdrive speed, V
PUP
> 4.5V 5 15.5
Write-0 Low Time (Notes
2, 16)
t
W0L
Overdrive speed 6 15.5
µs
Standard speed 1 15 - e Write-1 Low Time
(Notes 2, 17)
t
W1L Overdrive speed 1 2 - e
µs
I/O PIN, 1-Wire READ
Standard speed 5 15 - d Read Low Time
(Notes 2, 18)
t
RL Overdrive speed 1 2 - d
µs
Standard speed t
RL
+ d 15 Read Sample Time
(Notes 2, 18)
t
MSR Overdrive speed t
RL
+ d 2
µs