Command

entering

period

Blank

period

CTRL

LED

To Standby

Programmed

sequence

Command

entering

period

Blank

period

CTRL

LED

To Standby

Programmed

sequence

11

LP5560

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SNVS873D – AUGUST 2012 – REVISED JUNE 2016

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Figure 11. Run-Once Command

If CTRL signal is low after command entering period, blinking sequence is executed once the CTRL is set high

(Figure 12).

Figure 12. Delayed Run-Once Command

If device is in follow mode (mode bit is 0) the run-once command turns the LED on, and it is kept on as long as

CTRL is held high.

7.3.3 Training Mode

Figure 17 shows an example of a full training sequence with three pulses. Training mode starts with a training

start command. Training start command is followed by blank time during which no rising edges are allowed.

sequence and can vary from 350 µs to 8 ms. During parameter settings register values are incremented at speed

current-setting value is 3 (current-set register is incremented 3 times). If the parameter-setting pulse is shorter

than the calibration pulse, then the corresponding parameter is set to 0.

The next rising edge after calibration pulse starts LED driver current setting (I). LED driver current is recorded

once CTRL is pulled low. Note that there are empty low times before and after current setting pulse. For the

following pulses both CTRL high and CTRL low times are used to set the parameters. Next the CTRL high time

defines the LED current rise time setting for pulse 1 (R1). When R1 setting is started mode bit is set to 0. This

sets the LP5560 device into follow mode. Mode bit is set to 1 after first off time has been saved into register. This

means that at least one full pulse must be trained into memory to set the device into run mode.

CTRL low time after R1 defines the LED on time for pulse 1 (ON1). CTRL high time after ON1 sets the LED

current fall time (F1). CTRL low time after F1 sets pulse 1 off time (OFF1). Once rising edge of CTRL is detected

after first off time setting mode bit is set to 1 (run mode) and the number of pulses register (NOP[1:0]) is set to 1.

This indicates that one full pulse has been trained into memory.

Rise, on, fall, and off times for pulse 2 and 3 are set the same way as for pulse 1. Note that NOP register is

always incremented after OFFx time setting. This means that all pulse parameters (rise, on, fall, and off times)

must be trained for each pulse make it valid. The training sequence is ended with training end command.