STP16DPP05

Error detection mode functionality

DocID16518 Rev 4

19/34

7.2

Phase two: error detection

The 16 data bits must be set to “1” in order for all the outputs to be ON during error

detection. The data are latched by LE/DM1, after which the outputs are ready for the

detection process. When the microcontroller switches the OE/DM2

to LOW, the device

drives the LEDs to analyze if an OPEN or SHORT condition has occurred.

Figure 19: Detection diagram

The status of the LEDs is detected in at least 1 microsecond, and after this period the

microcontroller sets OE/DM2

to HIGH state and the output data detection result is sent

to the microcontroller via SDO. Error detection mode and normal mode both use the same

data format. As soon as all the detection data bits are available on the serial line, the

device may return to normal mode of operation. To re-detect the status, the device must

first return to normal mode and reenter error detection mode.