DocID024315 Rev 6

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STAP16DPS05

Detection mode functionality

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7.2

Phase two: “error detection”

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

The data are latched by LE/DM1 and after that the outputs are ready for the detection

process. When the microcontroller switches the OE/DM2 to LOW, the device drives the

LEDs in order to analyze if an OPEN or SHORT condition has occurred.

The LED status is detected at least in 1 microsecond (minimum) and after this time the

microcontroller sets OE/DM2 in high state and the output data detection result goes to the

microprocessor via SDO.

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 go back to normal mode

of operation. To re-detect the status, the device must go back in normal mode and re-enter

error detection mode.

Figure 15. Detection diagram