L9826
5.2.2
Functional description
Via 8-bit SPI for all the outputs
Control data are transmitted to SDI through a microcontroller in configuration master. The
device is selected when NCS signal is low. The 8-bit command data are transmitted into
L9826 shift registers every CLK falling edge (see Figure 6 for SPI signals timing).
The NCS rising edge latches the new data from the shift register to the driver and the output
are driven following the commands just sent.
The digital filter between NCS and the output latch ensures that the data are transferred
only after 8 CLK cycles or multiple of 8 CLK cycles since the last NCS falling edge.
The NCS changes only at low CLK.
Figure 5 shows the control register structure and in the detail its control-bit, while in the
Table 7 are summarized the controls outputs via SPI or dedicated input pins (NON1 and
NON2).
Figure 5. Output control register structure
-3"
,3"
1 1 1 1 1 1 1 1
Figure 6. Timing of the serial interface
.#3
TSCLCH THCLCL
TCLH
TCLL
#,+
TCSDV
TPCLD
3$/
NOT DEFINED
TSCLD
$
THCLD
3$)
$
$
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
#ONTROLBIT OUTPUT
'!0'03
TSCLCL
THCLCH
TPCHDZ
$
$
'!0'03
Doc ID 7214 Rev 10
13/19