DS1922T-F5 MAXIM [Maxim Integrated Products], DS1922T-F5 Datasheet - Page 41

• Manufacturer Part Number: DS1922T-F5
• Description: Temperature Logger iButton With 8kB Datalog Memory
• Manufacturer: MAXIM [Maxim Integrated Products]

MASTER-TO-SLAVE
For a write-one time slot, the voltage on the data line must have crossed the V
low time t
threshold until the write-zero low time t
during the entire t
time t
Figure 13. Read/Write Timing Diagram
Write-One Time Slot
Write-Zero Time Slot
Read-Data Time Slot
SLAVE-TO-MASTER
A read-data time slot begins like a write-one time slot. The voltage on the data line must remain below V
read low time t
data line low; its internal timing generator determines when this pulldown ends and the voltage starts rising again.
When responding with a 1, the DS1922L/T does not hold the data line low at all, and the voltage starts rising as
soon as t
REC
before it is ready for the next time slot.
RL
W1LMAX
V
V
V
is over.
IHMASTER
IHMASTER
IHMASTER
V
V
V
V
V
V
ILMAX
ILMAX
ILMAX
RL
V
V
V
V
V
V
PUP
PUP
PUP
0V
0V
0V
is expired. For a write-zero time slot, the voltage on the data line must stay below the V
TH
TH
TH
W0L
TL
TL
TL
is expired. During the t
or t
t
F
t
t
F
F
W1L
RESISTOR
RESISTOR
RESISTOR
window. After the V
t
RL
t
W1L
ε
δ
W0LMIN
RL
window, when responding with a 0, the DS1922L/T starts pulling the
Sampling
Window
Master
is expired. The voltage on the data line should not exceed V
t
TH
W0L
t
MSR
threshold has been crossed, the DS1922L/T needs a recovery
41 of 50
MASTER
MASTER
MASTER
t
SLOT
t
t
SLOT
SLOT
TH
t
REC
DS1922L/T
threshold before the write-one
t
REC
DS1922L/DS1922T
TL
until the
ILMAX
TH