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LP5024: Trouble getting the LP5024 to turn on LEDS

Part Number: LP5024


Incorporated a LP5024 on a design without doing proper investigation...
Find my LP5024 using the broadcast address and the address set (ADDR0 and ADDR1 pulled down to GND)

Im using 3v3 and measure 1.7v on the vcap.
LED's are common anode RGB from Inolux (IN-S66TATRGB)

Im driving them directly of USB so I measure about 5V on them...

This is the output from my attempt to get them lit up. Nothing happens

*********************** OUTPUT **************************************

I2C scanner. Scanning ...
Found address: 40 (0x28)
Found address: 60 (0x3C)
Found 2 device(s).

Enable Pin is:2 setting to HIGH

Wrote 64 to MYLP_DEVICE_CONFIG0 address
Reading from CONFIG0 = 64
Reading from CONFIG1 = 60 (Which is default)

Setting LED0 color to RGB=128,128,128 using address 0x0F 0x10 0x11
Reading from 0x0F=128
Reading from 0x10=128
Reading from 0x11=128

Setting LED0 brightness to 128 using address 0x07
Reading MYLP_LED0_BRIGHTNESS + ledNumber = 128
Setting LED1 color to RGB=255,0,0 using address 0x12 0x13 0x14
Reading from 0x12=255
Reading from 0x13=0
Reading from 0x14=0

Setting LED1 brightness to 128 using address 0x8
Reading MYLP_LED0_BRIGHTNESS + ledNumber = 128
Setting LED2 color to RGB=255,255,0 using address 0x15 0x16 0x17
Reading from 0x15=255
Reading from 0x16=255
Reading from 0x17=0

Setting LED2 brightness to 128 using address 0x9
Reading MYLP_LED0_BRIGHTNESS + ledNumber = 128
Setting LED3 color to RGB=0,255,0 using address 0x18 0x19 0x1A
Reading from 0x18=0
Reading from 0x19=255
Reading from 0x1A=0

Setting LED3 brightness to 128 using address 0xA
Reading MYLP_LED0_BRIGHTNESS + ledNumber = 128
Setup complete

  • Hi,

       Proper engineer has been assigned to look at this and will reply to you soon.

  • Hi again,

    Initial reported problem is resovled and LED's are tuning on when addresses indfividually. Next issue is that I cannot get the bank functionality to work.

    And one LED is less bright than the others using the same brightness setting. 

    I have arranged LEDs so that 0-2 channel is connected to a single RGB led and the other 3-7 are assigned to 3 RGB leds ... Banking is done by assigning channel 3-7 sending 0xf8 to LED_CONFIG0 (0x02). Then setting bank brightness via address 0x03 to say 200 (should be 255 by default).... Setting BANK_A_COLOR to 255 ... Nothing happens..

    Also cannot figure out why LED0 is so much more dim than the other ones. Maybe try swapping out that LED for a new one?? The red LED in the "center" of the PCB.

  • Hi Fredrik,

    1) It should be OK to set bank control in your setting (0xF8 to register 0x02; 0xC8 to register 0x03; 0xFF to register 0x04) and I tried in EVM to confirm it successfully. Have you configured the Device_config0 (0x40 to register 0x00) to enable the device before setting bank? Also you can attach your code for us to debug.

    2) Can you measure the forward current of LEDs in your board? it is more effective to determine if the device have abnormal output.
    And do LEDs have common anode connection or red one powered by individual supply? Red LED have smaller forward voltage than green and blue. Normally it would be slightly lighter in the same current.