Hello,
I need to make a measurement with a photodiode 100-300us after a high power LED blinks for 100us. Although I feed the LED from a separate LDO (I also tried SMPS), the collapse and recovery trend in the LED voltage creates the strange shape at the output of the transimpedance amplifier, which you can see in the oscilloscope image below.
I have a space question, I cannot use large materials. I put a few 100uF 1206 capacitors in parallel with the output of the LDO feeding the LED, I could only decrease the amplitude.
I use 1W power leds with low side switch.The LED and the photodiode need to be side by side, so I need to ensure that the supply voltage does not collapse or I need to be able to control the collapse.
What do you think I should do?
2 analog out (pd)
3 LED supply voltage
