LTC2485 LINER [Linear Technology], LTC2485 Datasheet - Page 13

• Manufacturer Part Number: LTC2485
• Description: 24-Bit ?? ADC with Easy Drive Input Current Cancellation and I2C Interface
• Manufacturer: LINER [Linear Technology]

APPLICATIO S I FOR ATIO
The START and STOP Conditions
A START condition is generated by transitioning SDA from
HIGH to LOW while SCL is HIGH. The bus is considered to
be busy after the START condition. When the data transfer
is finished, a STOP condition is generated by transitioning
SDA from LOW to HIGH while SCL is HIGH. The bus is free
again a certain time after the STOP condition. START and
STOP conditions are always generated by the master.
When the bus is in use, it stays busy if a repeated START
(Sr) is generated instead of a STOP condition. The
repeated START (Sr) conditions are functionally identical
to the START (S).
SDA
SCL
t
f
S
U
t
t
HD;STA
LOW
U
Figure 2. Definition of Timing for F/S-Mode Devices on the I
t
r
t
HD;DAT
W
t
SU;DAT
t
HIGH
U
t
r
t
SU;STA
Data Transferring
After the START condition, the I
transfer is set between a master and a slave. Data is
transferred over I
followed by an acknowledge bit, therefore each group
takes nine SCL cycles. The transmitter releases the SDA
line during the acknowledge clock pulse and the receiver
issues an Acknowledge (ACK) by pulling SDA LOW or
leaves SDA HIGH to indicate a Not Acknowledge (NAK)
condition. Change of data state can only happen while SCL
is LOW.
Sr
t
HD;STA
2
2
C in groups of nine bits (one byte)
C-Bus
t
t
SP
SU;STO
t
r
2
P
C bus is busy and data
t
BUF
LTC2485
S
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