Datasheet

DS1089L
3.3V Center Spread-Spectrum EconOscillator™
____________________________________________________________________ 11
SDA
SCL
t
HD:STA
t
LOW
t
HIGH
t
R
t
F
t
BUF
t
HD:DAT
t
SU:DAT
REPEATED
START
t
SU:STA
t
HD:STA
t
SU:STO
t
SP
STOP START
Figure 5. I
2
C AC Characteristics
SLAVE
ACK
10 1
1
R/WA0*A1*
SLAVE
ACK
A2*
MSB
LSB
DEVICE IDENTIFIER
DEVICE
ADDRESS
READ/
WRITE
MSB LSB
COMMAND/REGISTER ADDRESS
SLAVE
ACK
MSB LSB
b7 b6 b5 b4 b3 b2 b1 b0
SLAVE
ACK
STOP
*THE ADDRESS DETERMINED BY A0, A1, AND A2 MUST
MATCH THE ADDRESS SET IN THE ADDR REGISTER.
DATA
TYPICAL I
2
C WRITE TRANSACTION
EXAMPLE I
2
C TRANSACTIONS (WHEN A0, A1, AND A2 ARE ZERO)
A) SINGLE BYTE WRITE
-WRITE PRESCALER
REGISTER TO 128
B) SINGLE BYTE READ
-READ PRESCALER
REGISTER
START
START
START
B0h
B0h
SLAVE
ACK
SLAVE
ACK
02h
02h
SLAVE
ACK
SLAVE
ACK
DATA
SLAVE
ACK
STOP
10110000
10110000
b7 b6 b5 b4 b3 b2 b1 b0
00000010 10000000
10000000
00000010
REPEATED
START
DATA
MASTER
NACK
STOP
SLAVE
ACK
10110001
B1h
Figure 6. I
2
C Transactions
Applications Information
Power-Supply Decoupling
To achieve the best results when using the DS1089L,
decouple the power supply with 0.01µF and 0.1µF
high-quality, ceramic, surface-mount capacitors.
Surface-mount components minimize lead inductance,
which improves performance, and ceramic capacitors
tend to have adequate high-frequency response for
decoupling applications. These capacitors should be
placed as close to the V
CC
and GND pins as possible.
Stand-Alone Mode
SCL and SDA cannot be left floating even in stand-
alone mode. If the DS1089L will never need to be pro-
grammed in-circuit, including during production
testing, SDA and SCL can be connected high.