AN4460 datasheet(6/54 Pages) STMICROELECTRONICS

6 / 54 page

Demonstration board features

AN4460

6/54

DocID026129 Rev 1

Demonstration board features

The STEVAL-ILL057V1 demonstration board implements the following features:

 Four independent LED channels (external LEDs)

 3 to 10 LEDs per channel, connected in series

 Average LED current independently adjustable from 245 mA to 1065 mA with

~82 mA/step resolution

 LED brightness adjustable via PWM dimming (256 steps independent for each channel)

 Board power supply voltage (VLED_PW) from 12 V to 48 V based on the longest LED string

(external AC-DC power supply not included)

 Real-time fault detection and protection, such as open or short-circuit, independent for

each channel

 Board configuration (chain current, LED numbers, etc.) accessible via USB-UART

interfaces

 Three buttons to adjust the LED brightness for each channel

 Two status LEDs: green = ready-run, red = fault

Warning:

The user is responsible for configuring correctly the board

before connecting any LED string.

The user configures the right values according to the following parameters:



Number of LEDs connected on each channel (from 3 to 10)



Average LED current desired on each LED channel (from 245 mA to 1065 mA)



200 Hz PWM dimming duty cycle for each LED channel (from 0% to 100% in 256

steps)



Board power supply voltage (from 12 V to 48 V)

The number of LEDs, the current and the PWM dimming working point can be set through

the command interpreter accessible via the serial interface (Section 7.3 on page 28).

Alternatively, PWM dimming can also be manually adjusted via two on-board buttons.

The firmware installed on the STLUX385A automatically computes, for each LED string:



Primary frequency upper and lower limits (400 kHz to 15 kHz with frequency step

generated by PLL at 96 MHz - auto-setup)



Primary frequency duty cycle depending on the selected current, number of LEDs and

power voltage.

AN4460 Datasheet(PDF) 6 Page - STMicroelectronics

AN4460 Datasheet(HTML) 6 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54

Datasheet Download

Link URL