LP5030: LP5030 design review

Hi Mukesh,

1. yes, the address pins can be connected to VCC or GND through the resistor.
2. There are 3 cases, suppose the VCC = VLED = 3.3V, LED forward voltage = 2.5V, take LP5030 as an example.
   1. when the driver in shutdown mode, EN is pulled down, the power dissipation of the driver = VCC * I_Shutdown = 3.3V * 1uA = 0.0033 mW;
   2. when the driver in standby (chip_en = 0b) mode or power save mode (all channels off >30ms), the power dissipation of the driver = VCC * I_Standby  or I_Powersave = 3.3V * 12uA = 0.0396 mW;
   3. when the driver in normal mode (all channels on and output current, suppose output 10mA per channel), power dissipation of the driver = VCC * I_Normal + (VLED - LED_Forward) * Iout * Channel Number = 3.3V * 10mA + (3.3V - 2.5V) * 10mA * 30 = 273 mW

And please note that in the 3rd case, the (VLED - LED_Forward) should be larger than the max VSAT to make sure the channel can output the setting current.

Best regards,

Felix

Hi Felix, 

Thanks for the details, we'll calculate the values and let you know our observations. 

1. Is it advisable to have Decaps for the LEDs?

2. We're using individual white LEDs not RGB on 28 channels. I hope the Individual brightness control can be achieved through colour intensity. Please confirm. 

Regards, 

Mukesh

Hi Felix, 

I hope the datasheets for the LP50xx series are largely comparable, with no major differences. Is that correct? 

Regards, 

Mukesh

Hi Mukesh,

1. No, no need to place capacitor for output channel;
2. Yes, each channel brightness can be controlled individually through corresponding OUTx_COLOR register;
3. Yes, no major differences, except for the channel number.

Best regards,

Felix