ML6440
START
S DATA
t
t
RISE
FALL
All Other S DATA Transitions Must Occur While S CLK is Low
t
SET/START
S CLK
STOP
START: A Falling Edge on the S DATA While S CLK is Held High
STOP: A Rising Edge on the S DATA While S CLK is Held High
Figure 2. Definition of START & STOP on Serial Data Bus
S DATA
MSB
A7
MSB
D7
A6
2
A1
7
A0
8
D6
11
D1
16
D0
17
STOP
S CLK
0
1
9
10
18
S CLK: 9th pulse strobes address decoder
S CLK: Rising edge enables data transfer
S DATA: Value set to A6, Device Address (MSB-1)
S CLK: Falling edge disables data transfer
S CLK: Rising edge enables data transfer
S DATA: Value set to A7, Device Address MSB
S DATA: Rising edge with S CLK Hi = STOP
S DATA: Value set low in prep for STOP
S CLK: 18th pulse strobes data shift register
S CLK: Rising edge enables data transfer
S DATA: Value set to D6, Data MSB-1
S CLK: Falling edge disables data transfer
S CLK: Rising edge enables data transfer
S DATA: Value set to D7, Data MSB
S CLK: Falling edge in prep for first address transfer
S DATA: Falling edge w/S CLK high means start of sequence
Figure 3. Definition of DATA FORMAT on Serial Data Bus
S DATA
STROBE (ACK)
Ø
‘1’
‘0’
2
‘1’
‘1’
‘0’
‘0’
6
‘1’
7
‘1’
8
Ø
9
D7
A
D6
B
D5
D4
D3
D2
D1
G
D0
H
DEVICE ADDR = ‘B3’
CONTROL REGISTER
S CLK
0
1
3
4
5
C
D
E
F
I
S CLK: Address decode strobed on 9th clock
[Data is ‘don’t care’ during strobe]
S
: Final Clock strobes data into register
DATA
Control register, load MSB first
S DATA: ‘1011 0011’ shifted on next 8 clocks
S CLK: Falling edge in prep for device address transfer
Figure 4. Typical Serial Bus Command
9
MICRO-LINEAR [ MICRO LINEAR CORPORATION ]
