AK2363 Datasheet, PDF (11/33 Pages) Asahi Kasei Microsystems – Radio Signaling LSI

ASAHI KASEI
[AK2363]
Digital AC Timing
1) Serial interface timing
The AK2363 writes and reads data via the three-wire synchronous serial interface by means of CSN,
SCLK, and SDATA.
SDATA (serial data) consists of a write/read identification bit (R/W), a register address (starting from
the MSB, A3 to A0), and control data (starting from the MSB, D7 to D0).
Write (WRITE instruction)
CSN
SCLK
SDATA
(Input)
SDATA
(Output)
R/W A3 A2 A1 A0
Hi-Z
Read (READ instruction)
D7 D6 D5 D4 D3 D2 D1 D0
CSN
SCLK
SDATA
(Input)
SDATA
(Output)
R/W A3 A2 A1 A0
Hi-Z
Hi-Z
D7 D6 D5 D4 D3 D2 D1
D0
R/W: This bit indicates whether an access to a register is a write access or read access.
If this bit is Low, a write is performed; if the bit is High, a read is performed.
A3 to A0: These bits indicate the address of the register to be accessed.
D7 to D0: Data to be written to or read from the register.
<1> CSN (chip select) is normally set to the high level.
When CSN is set to the low level, the serial interface becomes active.
<2> When a write operation is performed, an identification bit, an address, and data are input from
SDATA in synchronization with the rising edges of 14 SCLK clock pulses while CSN is low.
During the time between address A0 and data D7, SDATA must be held low.
When a read operation is performed, an identification bit and an address are input from SDATA in
synchronization with the rising edges of the first five clock pulses of SCLK, and data at a specified
address is output in synchronization with the falling edges of the following nine clock pulses while
CSN is low.
Note that data between address A0 and data D7 is undefined.
During the data output period in the latter nine clock pulses of SCLK, the input to SDATA must be
Hi-Z.
<3> Write and read settings are made on the assumption that 14 clock pulses are input from SCLK
while CSN is low.
Note that if clock pulses more than or less than 14 clock pulses are input, data cannot be set
correctly.
MS0583-E-01
- 11 -
2008/06