DS2506
AC ELECTRICAL CHARACTERISTICS OVERDRIVE SPEED
(VPUP=2.8V to 6.0V; -40°C to 70°C)
PARAMETER
Time Slot
Write 1 Low Time
Write 0 Low Time
Read Data Valid
Release Time
Read Data Setup
Recovery Time
Reset Time High
Reset Time Low
Presence Detect High
Presence Detect Low
SYMBOL
tSLOT
MIN
TYP
MAX
16
UNITS
µs
NOTES
6
1
6
tLOW1
tLOW0
tRDV
2
µs
16
µs
2
1.5
µs
12
5
tRELEASE
0
4
1
µs
tSU
µs
tREC
1
48
48
2
µs
tRSTH
µs
4
tRSTL
80
6
24
µs
tPDHIGH
µs
tPDLOW
8
µs
NOTES:
1. All voltages are referenced to ground.
2. VPUP= external pullup voltage.
3. Input load is to ground.
4. An additional reset or communication sequence cannot begin until the reset high time has expired.
5. Read data setup time refers to the time the host must pull the 1-Wire bus low to read a bit. Data is
guaranteed to be valid within 1 µs of this falling edge.
6. VIH is a function of the external pullup resistor and VPUP
.
7. 30 nanocoulombs per 72 time slots @ 5.0V.
8. At VCC=5.0V with a 5 kΩ pullup to VCC and a maximum time slot of 120 µs.
9. Capacitance on the data pin could be 800 pF when power is first applied. If a 5 kΩ resistor is used to
pullup the data line to VCC, 5 µs after power has been applied the parasite capacitance will not affect
normal communications.
10. Under certain low voltage conditions VILMAX may have to be reduced to as much as 0.5V to always
guarantee a presence pulse.
11. Operational temperature range for memory programming is -40°C to +50°C.
12. For read-data time slots the optimal sampling point for the master is as close as possible to the end
time of the tRDV period without exceeding 15 µs for regular speed or 2 µs for overdrive speed. For the
case of a read-one time slot, this maximizes the amount of time for the pull-up resistor to recover the
line to a high level. For a read-zero time slot it ensures that a read will occur before the fastest 1-Wire
device releases the line (tRELEASE = 0).
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DALLAS [ DALLAS SEMICONDUCTOR ]
