DS1922T Maxim, DS1922T Datasheet - Page 3

• Manufacturer Part Number: DS1922T
• Description: The DS1922L/T temperature logger iButtons® are rugged, self-sufficient systems that measure temperature and record the result in a protected memory section
• Manufacturer: Maxim

ELECTRICAL CHARACTERISTICS (continued)
(V
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Presence-Detect Low Time
Presence-Detect Sample Time
(Note 2)
IO PIN: 1-Wire WRITE
Write-Zero Low Time
(Notes 2, 14)
Write-One Low Time
(Notes 2, 14)
IO PIN: 1-Wire READ
Read Low Time
(Notes 2, 15)
Read Sample Time
(Notes 2, 15)
REAL-TIME CLOCK
Accuracy
Frequency Deviation
TEMPERATURE CONVERTER
Conversion Time
(Note 16)
Thermal Response Time
Constant (Note 17)
Conversion Error Without
Software Correction
Conversion Error with Software
Correction
PUP
= +3.0V to +5.25V.)
PARAMETER
Guaranteed by design, not production tested to -40°C or +125°C.
System requirement.
Maximum allowable pullup resistance is a function of the number of 1-Wire devices in the system and 1-Wire recovery
times. The specified value here applies to systems with only one device and with the minimum 1-Wire recovery times. For
more heavily loaded systems, an active pullup such as that found in the DS2480B may be required.
Capacitance on the data pin could be 800pF when V
2.5µs after V
V
V
Voltage below which, during a falling edge on IO, a logic 0 is detected.
TL
TH
and V
and V
TH
_______________________________________________________________________________________
TL
PUP
are functions of the internal supply voltage, which is a function of V
maximum specifications are valid at V
Temperature Logger iButton with 8KB
has been applied, the parasite capacitance does not affect normal communications.
SYMBOL
t
t
t
CONV
t
t
t
RESP
MSP
MSR
PDL
W0L
W1L
t
RL
F
Standard speed, V
Standard speed (Note 12)
Overdrive speed, V
Overdrive speed (Note 12)
Standard speed, V
Standard speed
Overdrive speed
Standard speed
Overdrive Speed, V
Overdrive speed (Note 12)
Standard speed
Overdrive speed
Standard speed
Overdrive speed
Standard speed
Overdrive speed
-40°C to +85°C
0°C to +125°C
8-bit mode
16-bit mode (11 bits)
iButton package
(Notes 18, 19)
(Notes 19, 20)
PUP
PUP
CONDITIONS
= 5.25V. In any case, V
is first applied. If a 2.2kΩ resistor is used to pull up the data line,
PUP
PUP
PUP
PUP
> 4.5V
> 4.5V
> 4.5V (Note 12)
> 4.5V (Note 12)
Data-Log Memory
TL
PUP
< V
and the 1-Wire recovery times. The
TH
t
t
RL
RL
71.5
-300
-600
MIN
240
7.5
60
60
65
60
30
< V
7
7
8
6
5
1
5
1
See RTC Accuracy
+
+
Accuracy graphs
Accuracy graphs
See Temperature
See Temperature
PUP
graphs
.
TYP
130
1.95 -
15 -
MAX
1.95
1.95
+60
+60
240
287
120
600
24
28
75
75
12
12
15
15
75
9
UNITS
month
PPM
min/
ms
μs
μs
μs
μs
μs
μs
°C
°C
s
3