Hi Team,
A customer used TPS63036 as LED driver based on Figure 2 in the application notes below.
The device works normally at an input voltage of 2V. However at 5V input the LED has difficulty turning on. He needs to turn on and off the power switch multiple times before the LED will turn on. There is also audible high frequency noises from the board. The output current is 5mA only but the issue is worst at 10mA. What could be the cause of this issue?
Here are the component values:
R1 = 51K
R2 = 11K
Rsense = 4.3 ohm
L1 = 1.5uH, TOKO 1286AS-H-1R5M
VF of LED = 2.7V
Here are the schematic diagram and PCB layout.PCB Layout-Top layer
PCB Layout - Bottom Layer
Regards,
Danilo