Datasheet

DS28E04-100: 4096-Bit 1-Wire Addressable EEPROM with PIO
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Read/Write Time Slots
Data communication with the DS28E04-100 takes place in time slots, which carry a single bit each. Write time slots
transport data from bus master to slave. Read time slots transfer data from slave to master. Figure 16 illustrates
the definitions of the write and read time slots.
All communication begins with the master pulling the data line low. As the voltage on the 1-Wire line falls below the
threshold V
TL
, the DS28E04-100 starts its internal timing generator that determines when the data line is sampled
during a write time slot and how long data is valid during a read time slot.
Figure 16. Read/Write Timing Diagram
Write-One Time Slot
RESISTOR MASTER
V
PUP
V
IHMASTER
V
TH
V
TL
V
ILMAX
0V
t
F
t
SLOT
t
W1L
ε
Write-Zero Time Slot
RESISTOR MASTER
t
REC
V
PUP
V
IHMASTER
V
TH
V
TL
V
ILMAX
0V
t
F
t
SLOT
t
W0L
ε
Read-Data Time Slot