www.austriamicrosystems.com/AS3561 Revision 0.11 - preliminary 11 - 18
AS3561
Data Sheet - Detailed Description
8 Detailed Description
8.1 I2C Control Interface
An I2C slave interface is implemented for read/write access of the internal registers. SCL is the corresponding clock input pin and SDA the data
input pin.
Access is done in 7-bit addressing mode, addresses for read and write are defined by
C0h = 11000000b ... write
C1h = 11000001b ... read
Figure 23. I2C block diagram
Figure 24. I2C Timing Definition
Table 4. I2C Timing Parameters
Symbol Parameter Condition Min Typ Max Unit
T
SP
Spike Insensitivity 50 100 ns
T
HI
High Clock Time
400 KHz clock speed
330 ns
T
LO
Low Clock Time 660 ns
T
SU
SDA has to change Tsetup
before rising edge of SCLK
30 ns
T
HD
no hold time needed for SDA
relative to rising edge of CSCL
-40 ns
T
HD;STA
Within start condition, after low going SDA, SCL has to stay constant
for the specified hold time
300 ns
T
SU;STO
After high going edgle of SCL, SDA has to stay constant for the
specified setup time before STOP or repeated start condition is
applied
100 ns
T
SU;STA
100 ns
I2C
Interface
SCL
SDA
Registers
10k
10k
AS3561
T
HD;STA
T
R
T
LO
T
HI
T
F
T
SU;DAT
T
SU;STA
T
HD;STA
T
SP
T
SU;STO
STOP
START
SR
SCL
SDA
