DS1629
21 of 23
DC ELECTRICAL CHARACTERISTICS: DIGITAL THERMOMETER
(2.7V d V
DD
d 5.5V, T
A
= -55癈 to +125癈, unless otherwise noted.)
PARAMETER
SYMBOL CONDITION MIN TYP MAX UNITS NOTES
DS1629 Thermometer
Error
T
ERR
-10癈 to +85癈
2.7V d V
DD
d
5.5V
?.0
癈
7
Resolution
0.062
0.5
癈
8
Conversion Time
t
T
400
1000
ms
AC ELECTRICAL CHARACTERISTICS: 2-WIRE INTERFACE
(2.2V d V
DD
d 5.5V, T
A
= -55癈 to +125癈, unless otherwise noted.)
PARAMETER
SYMBOL CONDITION MIN TYP MAX UNITS NOTES
SCL Clock Period
t
2.5
s
Data In Setup Time to
SCL Hi h
t
2
100
ns
Data Out Stable after
SCL Low
t
3
0
ns
SDA Low Setup Time
to SCL Low
START
t
4
100
ns
SDA High Hold Time
After SCL High
STOP
t
5
100
ns
Capacitance Load for
Each Bus Line
C
B
400
pF
9
In
i n
F
Cr stal Ca acitance
C
12.5
F
10
Note 3: Logic 0 voltage specified at a sink current of 4mA at V
DD
= 5.0V and 1.5mA at V
DD
= 2.2V.
Note 4: I/O pins of fast mode devices must not obstruct the SDA and SCL lines if V
DD
is switched off.
Note 5: Standby current specified with temperature conversions and clock oscillator/buffer shut down,
ALRM pin open, and SDA, SCL = V
DD
, 0癈 to +70癈.
Note 6: I
DDX
specified with ALRM pin open, and 0癈 to +70癈.
Note 7: See typical accuracy curve for specification limits outside the temperature range indicated.
Thermometer error is specified for 2.7V d V
DD
d 5.5V. Accuracy will degrade approximately 0.5癈 if
ALRM is sinking the maximum current.
Note 8: Thermometer resolution (in ?/SPAN>C) = 1/COUNT_PER_C(T). The calibration algorithm is such that
COUNT_PER_C and thus resolution varies over temperature (but is constant at a given temperature for a
given device) and from device to device.
Note 9: C
B
: Total capacitance of one bus line in pF.
Note 10: Refer to Application Note 58.
Note 11: Limits are 100% production tested at T
A
= +25癈 and/or T
A
= +85癈. Limits over the operating
temperature range and relevant supply voltage are guaranteed by design and characterization.