FX803 Datasheet, PDF (13/17 Pages) Sanyo Semicon Device – DC-DC Converter

Timing Information
Timing Diagrams
Figure 7 shows the timing parameters for two-way communication between the µController and the FX803 on the “C-BUS.”
Figure 8 shows, in detail, the timing relationships for “C-BUS” information transfer.
CHIP SELECT
t CSOFF
SERIAL CLOCK
t CSE
COMMAND DATA
76 54 3 2 10
MSB
LSB
REPLY DATA
ADDRESS/COMMAND
BYTE
Logic level is not important
Fig.7 “C-BUS” Timing Information
t NXT
t NXT
t CK
76 54 3 2 10
FIRST DATA BYTE
7 654 3 210
MSB
LSB
FIRST REPLY DATA BYTE
t CSH
76543 2 10
LAST DATA BYTE
76543 2 10
LAST REPLY DATA BYTE
t HIZ
NOT TO SCALE
Parameter
t
CSE
t
CSH
t_CSOFF
t
NXT
t
CK
t
CH
t
CL
t_CDS
t
CDH
t
RDS
t
RDH
t
HIZ
Min.
2.0
4.0
2.0
4.0
2.0
500
500
250
0
250
50.0
–
Typ.
–
–
–
–
–
–
–
–
–
–
–
–
Max.
–
–
–
–
–
–
–
–
–
–
–
2.0
Unit
µs
µs
µs
µs
µs
ns
ns
ns
ns
ns
ns
µs
Notes
(1) Command Data is transmitted to the peripheral MSB (Bit 7) first, LSB (Bit 0) last.
Reply Data is read from the FX803 MSB (Bit 7) first, LSB (Bit 0) last.
(2) Data is clocked into the FX803 and into the µController on the rising Serial Clock edge.
(3) Loaded data instructions are acted upon at the end of each individual, loaded byte.
(4) To allow for differing µController serial interface formats, the FX803 will work with either polarity Serial
Clock pulses.
t _CK
t_CL
t_CDS
t _CH
t_CDH
70% V_DD
30% V_DD
SERIAL CLOCK
(from µC)
COMMAND DATA
(from µC)
REPLY DATA
(to µC)
t_RDS
Fig.8 “C-BUS” Timing Relationships
13
t_RDH
NOT TO SCALE