Questions regarding protection resistor values for UV LED and the electrical operating conditions

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1

------Question for UV5TZ-395-30 Please Put your question below------

I am writing this message as I am part of a school research project doing optical analysis for water quality monitoring.
Could I request information on the following:

  1. What resistance values would you recommend to put in series with the UV Led to protect the UV LED?
  2. Is the UV LED able to operate under a sinusoidal signal ranging from 0V to its forward voltage? If so, what is the maximum frequency?
  3. Is the UV LED able to operate under a pulse signal ranging from 0V to its forward voltage? if so, what is the maximum frequency?

Thank you for your assistance in this matter.

2

Hello,

How many LEDs are you putting in series?

Here is a link to an LED in series calculator.
LED Series Resistor Calculator | DigiKey Electronics

3

  1. This is entirely application-dependent. The calculator Karl mentions may be useful.

  2. & 3) Not really, since the device does not pass current or emit light until the applied forward voltage is near the listed value. Characterizations of these behaviors are in the datasheet plots excerpted below. If one drives the device using a controlled current waveform however, the light emissions should track the waveform to a close first approximation and to rather high frequencies (MHz I’d expect) for direct-emission devices of this sort. The frequency response of phosphor-converted (e.g. white LEDs) is limited by the phosphor, and will be lower.

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4

Thank you for providing a link to calculate the resistance value.

5

Thank you for answering my questions.