LP8556: LP8556TMX-E02/NOPB Can't display LED

Hi Ning,

Some feedback for you:

1. On datasheet "8.6 Register Maps" has all the registers, could you please kindly ask our customer to list their registers' setting as the table shown? (Can be read through I2C)

2. Please let customer test the SW (when device start up and during normal operation) to see if the device is trying to work.

3. Please read address 02h through I2C to see which fault is indicated.

BR

Patrick

Dear Patrick,

I will feedback your information to customer,then will reply you.

Thanks

Hi Ning,

I'll wait for your reply.

BR

Patrick

Hi Patrick,

Pls kindly find attach file for SW waveform and their registers' setting ,any problem pls let me know.

Thanks

lp8556调试20221107.docx

Hi Ning,

1. At first the default value of address 0x01 is 0, so they are using only PWM to control brightness, but they also need to write address 0xA2 with 0x28 to enable backlight.

2. Then I noticed that customer write 0x05 to address 0x01, so they are using only registers to control brightness, did they write any data to address 0x00? Because 0x00 is the brightness code, the default value is 0, needed to be written other value to turn on LEDs.

BR

Patrick

Dear Patrick,

Thanks for your information,you mean first they need  to write address 0xA2 with 0x28 to enable backlight,sencond need to write other value to 0x00 to turn on LEDS.

I will send this to our customer,any feedback will let you know.

Thanks

Hi Ning,

I mean, if they are using PWM to control brightness, please follow the steps in "1", that is, write address 0x01 with 0, then write address 0xA2 with 0x28 to enable backlight.

If they are using I2C to write brightness code to control brightness, please follow steps in "2", that is, write 0x05 to address 0x01, then write other data to address 0x00 to change the brightness code.

BR

Patrick

Dear Patrick,

Noted,I will told them to try it.Then will reply you.

Thanks

Hi Ning,

I'll wait for your reply.

BR

Patrick

Dear Patric,

Have click reslove.

Thanks