I have a new AllinOne board in my Atrump E216.
We put a new HuiJing spindle encoder in it. (The old one was acting the same)
The power supply is right at 5.0V
All the signals are at 0.5V (low) 2.84V (high). Measured to DC Com.
It works intermittantly, but throws quadrature errors.
There is some noise from the VFD.
I will work on reducing the noise, but I am sure a higher (in spec.) signal would improve things.
Is the Voltage determined by pull-up resistors on the AllinOne?
If the Voltage is too low, can I add external pull ups on the signals?
What Determines Encoder Signal Voltage?
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kenmwallace
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eng199
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Re: What Determines Encoder Signal Voltage?
It is determined by the current output of the line drivers. Usually the line driver IC is some variation of 26LS31 (quad package). The receiving side has a termination resistor that will lower the voltage versus open circuit voltage. The line driver needs sufficient output current to still have the recommend voltage when driving the termination. External pull ups don't address the problem. Most likely they would shift high and low levels, bringing the low out of specification.