STLED524 datasheet(68/72 Pages) STMICROELECTRONICS

68 / 72 page

Application information

STLED524

68/72

DocID026217 Rev 1

6.3

Multiple devices in cascade

The STLED524 multiple devices can be linked in cascade according to Figure 30.

Figure 30. STLED524 cascade

•

Each device in cascade needs a controlled SS input separately.

•

RESET/PWRDN, SYNC, SCK, MISO and MOSI pins are connected in parallel.

•

CLKOUT of nth device is connected to CLKIN of the (n+1)th device.

•

CLKIN of the 1st device does not have to be connected, if internal clock of the 1st

device is used to provide clock for the whole cascade.

•

Another possibility for CLOCK signal is to connect all CLKIN pins to an external clock.

6.3.1

Position means position of the device in cascade:

CLKIN bit of the first device is set to 0, because the first device uses its internal clock.

CLKOUT bit of the last device is set to 0, because there is no other device connected.

SYNCEN bit of all devices has to be set to 1.

SYNCSEL bit can be either 0 or 1, but the value has to be the same as all devices in

cascade.

GIPG2103141214LM

Table 71. Cascade register setup

Position

CLKIN

CLKOUT

SYNCEN

SYNCSEL

2 to (n-1)

STLED524 数据表(PDF) 68 Page - STMicroelectronics