LED7708

List of figures

Doc ID 022698 Rev 1

5/53

List of figures

Figure 1.

Basic application circuit schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 2.

Pin connection (through top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 3.

Simplified block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 4.

Soft-start waveforms (standalone operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 5.

Simplified output regulation circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 6.

Effect of slope compensation on small inductor current perturbation (D>0.5) . . . . . . . . . . 26

Figure 7.

Simplified serial interface block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 8.

Timing diagram related to a DEVCFGx write operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 9.

16-bit data format, write operation to the brightness register . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 10.

256-bit data format, write operation to the brightness registers . . . . . . . . . . . . . . . . . . . . . 32

Figure 11.

192-bit data format, write operation to the brightness registers . . . . . . . . . . . . . . . . . . . . . 32

Figure 12.

Dimming signals and synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 13.

Normal timing mode waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 14.

Inverted timing mode waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Figure 15.

Dimming waveform and GSSY output pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 16.

Dimming waveform triggered by GSSY input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Figure 17.

Internal signals connected to the XFLT pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Figure 18.

Channels current gain adjust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Figure 19.

Continuous reading mode disabled, 1x256-bit data format . . . . . . . . . . . . . . . . . . . . . . . . 46

Figure 20.

Continuous reading mode enabled, 1x256-bit data format . . . . . . . . . . . . . . . . . . . . . . . . . 47

Figure 21.

VFQFPN48 (7 x 7 x 1.0 mm.) package outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Figure 22.

Recommended PCB footprint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51