DS1990 DALLAS [Dallas Semiconductor], DS1990 Datasheet - Page 7

• Manufacturer Part Number: DS1990
• Description: Serial Number iButton
• Manufacturer: DALLAS [Dallas Semiconductor]

READ/WRITE TIMING DIAGRAM Figure 6
Write-One Time Slot
Write-Zero Time Slot
Read-Data Time Slot
RESISTOR
MASTER
DS1990A
60 s
1 s
1 s
60 s
1 s
60 s
1 s
0
1 s
t
t
RDV
SU
= 1 s
t
RELEASE
7 of 10
= 15 s
t
t
t
t
t
REC
REC
LOWR
t
t
t
LOW1
REC
SLOT
LOW0
SLOT
<
<
<
< 45 s
< 15 s
< 15 s
< 120 s
< 120 s
< t
SLOT
< 120 s
DS1990A