Hey guys,
I have a square wave signal from 3V to 0V. When the signal is 3V, our two IR LEDs are off. When it is 0, the LEDs are on.
I'd like to use a transistor or FET to control the LEDs (the IC which generates the signal also acts as a current sink) so we can put more current through the LEDs without burning the chip.
Most applications of FETs and transistors I've seen have the FETs used as switches that are normally open and only close when a voltage is applied to the gate. In my case, I want the exact opposite. I want the switch to be open when 3V is applied to the gate, and I want it to be closed (LEDs on) when 0V is applied. I'm using this for infrared communication at approximately 38400 baud rate.
There are many types of FETs out there...what is the best type of FET for this? A JFET? A depletion mode MOSFET? I do not have too much experience with FETs so I will be doing some research, but thought maybe someone here could give me a head start or at least some suggestions.
Thanks!
I have a square wave signal from 3V to 0V. When the signal is 3V, our two IR LEDs are off. When it is 0, the LEDs are on.
I'd like to use a transistor or FET to control the LEDs (the IC which generates the signal also acts as a current sink) so we can put more current through the LEDs without burning the chip.
Most applications of FETs and transistors I've seen have the FETs used as switches that are normally open and only close when a voltage is applied to the gate. In my case, I want the exact opposite. I want the switch to be open when 3V is applied to the gate, and I want it to be closed (LEDs on) when 0V is applied. I'm using this for infrared communication at approximately 38400 baud rate.
There are many types of FETs out there...what is the best type of FET for this? A JFET? A depletion mode MOSFET? I do not have too much experience with FETs so I will be doing some research, but thought maybe someone here could give me a head start or at least some suggestions.
Thanks!
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