DS1820
021497 25/27
AC ELECTRICAL CHARACTERISTICS:
(–55
°
C to +125
°
C; V
DD
=3.6V to 5.5V)
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
NOTES
Temperature Conversion Time
t
CONV
200
500
ms
Time Slot
t
SLOT
60
120
µ
s
Recovery Time
t
REC
1
µ
s
Write 0 Low Time
r
LOW0
60
120
µ
s
Write 1 Low Time
t
LOW1
1
15
µ
s
Read Data Valid
t
RDV
15
µ
s
Reset Time High
t
RSTH
480
µ
s
Reset Time Low
t
RSTL
480
4800
µ
s
Presence Detect High
t
PDHIGH
15
60
µ
s
Presence Detect Low
t
PDLOW
60
240
µ
s
Capacitance
C
IN/OUT
25
pF
NOTES:
1. Temperature conversion will work with
±
2
°
C accuracy down to V
DD
= 3.4 volts.
2. All voltages are referenced to ground.
3. Logic one voltages are specified at a source current of 1 mA.
4. Logic zero voltages are specified at a sink current of 4 mA.
5. I
DD
specified with V
CC
at 5.0 volts.
6. Active current refers to either temperature conversion or writing to the E
2
memory. Writing to E
2
memory con-
sumes approximately 200
µ
A for up to 10 ms.
7. Input load is to ground.
8. Standby current specified up to 70
°
C. Standby current typically is 5
µ
A at 125
°
C.
9. See Typical Curve for specification limits outside the 0
°
C to 70
°
C range. Thermometer error reflects sensor accu-
racy as tested during calibration.
10. Typical accuracy curve valid for 4.3V
≤
V
DD
≤
5.5V.
1–WIRE WRITE ONE TIME SLOT
START OF NEXT CYCLE
t
REC
t
LOW1
t
SLOT
