Dallas DS1821 - Ac Electrical Characteristics

DS1821
16 of 18
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
0.4 1.0 s
EEPROM Write Time t
WR
10 50 ms
Time Slot t
SLOT
60 120 µs 1
Recovery Time t
REC
1 µs 1
Write 0 Low Time t
LOW0
60 120 µs 1
Write 1 Low Time t
LOW1
1 15 µs 1
Read Data Valid t
RDV
15 µs 1
Reset Time High t
RSTH
480 µs 1
Reset Time Low t
RSTL
480 µs 1,2
Presence Detect High t
PDHIGH
15 60 µs 1
Presence Detect Low t
PDLOW
60 240 µs 1
V
DD
Low to Mode Toggle Clock Low t
PC
100 ns 1,3
Mode Toggle Clock 16 High to V
DD
High
t
CP
100 ns 1
Mode Toggle Clock Pulse Low Time t
CL
0.1 10 µs 1
Mode Toggle Clock Pulse High Time t
CH
0.1 µs 1
Mode Toggle Clock High-to-Low or
Low-to-High Transition Time
t
T
100 ns 1
Capacitance C
IN/OUT
25 pF
NOTES:
1. Refer to timing diagrams in Figure 13.
2. If t
RSTL
> 960 μs, a power-on-reset may occur.
3. Time required for part to disable thermostat output.