I want to convert an optical encoder's signal from a 5V to a 12V output. This is because the wire connecting the encoder to the MCU is a very long one (about 20m long) and I do not trust a clean 5V signal traveling that far without being affected by important voltage drop and ambient noise (EMI, for instance, even though I'll be using shielded cable).
So I simulated a simple, single channel, 2 transistor level shifter working at 60 kHz in LTSpice and the results seem encouraging. What I did was add an inductor between the level shifter's output and the voltage divider that I'll be placing at the PCB to connect it to my MCU, so as to simulate those 20m of #24 wire.
What I did was use the following pages to calculate the wire's inductance and resistance:
There are a couple of fields that I don't understand in LTSpice's inductor model, and those are the parallel resistance, and the parallel capacitance. How can I calculate those values?
So I simulated a simple, single channel, 2 transistor level shifter working at 60 kHz in LTSpice and the results seem encouraging. What I did was add an inductor between the level shifter's output and the voltage divider that I'll be placing at the PCB to connect it to my MCU, so as to simulate those 20m of #24 wire.
What I did was use the following pages to calculate the wire's inductance and resistance:
http://chemandy.com/calculators/roundwireinductancecalculator.htm
http://chemandy.com/calculators/roundwireresistancecalculator.htm
http://chemandy.com/calculators/roundwireresistancecalculator.htm
There are a couple of fields that I don't understand in LTSpice's inductor model, and those are the parallel resistance, and the parallel capacitance. How can I calculate those values?
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