DS1721 Datasheet, PDF (15/16 Pages) Dallas Semiconductor – 2-Wire Digital Thermometer and Thermostat

DC ELECTRICAL CHARACTERISTICS:
DIGITAL THERMOMETER
PARAMETER
SYMBOL CONDITION
DS1721
Thermometer Error
T_ERR
-10°C to +85°C
Resolution
9-bit
Conversions
10-bit
Conversion Time
t_CONVT
Conversions
11-bit
Conversions
12-bit
Conversions
DS1721
(-55°C to +125°C; 2.7V ≤ V_DD ≤ 5.5V)
MIN TYP MAX UNITS NOTES
±1.0
°C
5
9
12
bits
125 150
250 300
ms
500 600
1000 1200
AC ELECTRICAL CHARACTERISTICS:
2-WIRE INTERFACE
(-55°C to +125°C; V_DD=2.7V to 5.5V)
PARAMETER
SYMBOL CONDITION MIN TYP MAX UNITS NOTES
SCL Clock
Frequency
f_SCL
Fast Mode
0
Standard Mode
0
400
100
KHz
Bus Free Time
Between a STOP
and START
t_BUF
Fast Mode
1.3
Standard Mode 4.7
µs
Condition
Hold Time
(Repeated) START
Condition
t_HD:STA
Fast Mode
0.6
Standard Mode 4.0
µs
6
Low Period of
SCL Clock
t_LOW
Fast Mode
1.3
Standard Mode 4.7
µs
High Period of
SCL Clock
t_HIGH
Fast Mode
0.6
Standard Mode 4.0
µs
Setup Time for a
Repeated START
Condition
t_SU:STA
Fast Mode
0.6
Standard Mode 4.7
µs
Data Hold Time
t_HD:DAT
Fast Mode
Standard Mode
0
0
0.9
µs
7
Data Set-up Time
t_SU:DAT
Fast Mode
100
Standard Mode 250
ns
8
Rise Time of both
SDA and SCL
Signals
t_R
Fast Mode 20+0.1
Standard Mode C_B
300
1000
ns
8
Fall Time of both
SDA and SCL
Signals
t_F
Fast Mode 20+0.1
Standard Mode C_B
300
1000
ns
9
Set-up time for
STOP Condition
t_SU:STO
Fast Mode
0.6
Standard Mode 4.0
µs
Capacitive Load for
each Bus Line
C_b
400
pF
9
Input Capacitance
C_I
5
pF
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