DocID025366 Rev 2

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AN4374

Output error detection

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Output error detection

Stopping the normal activity of the display and turning on all driver channels allows the error

detection to be performed and failed LED or display defects to be checked. The error

detection is active when the CFG -7 bit in the configuration register is "0". The diagnostics is

performed as shown in Figure 14:

Figure 14. Normal detection sequence

•

The LED has to be selected turning on the relative channel on the switch register

(powering on or off the output channels); the brightness register value for this channel

cannot be zero.

•

The appropriate digital key must be sent (seeTable 4 and Figure 15) to choose the type

of detection (open, short or combined):

AM16863v1

Normal detection sequence

Read error detection result on

SDO in 16 clock pulses after

detection end command

Turn on LED by PWCLK

pulses for at least 1 µs

Send open, short or combined

error detection start command

by LE digital keys

Select LED to be turned on and

checked in switch register

data; brightness for selected

channels cannot be zero.

Select normal error detection mode

on CFG register (bit 7 = “0”)

Send error detection end

command by LE digital key