maurobarreca
Member
Hi, I was studying Paul's DMX Signal Transmitter and Receiver for a project and it's hard for me to understand the role of the voltage dividers applied to the data signals.
(Sorry if the schematics are messy)
For what I understand the input signal on the transmitter and the output signal on the receiver are tied to the center of a voltage divider (5v-47K on one side, 100K-GND on the other). Paul explains on the transmitter's OSH Park page that the output of the receiver outputs a 5v signal, so I think those voltage dividers are there to step up the signal from the Teensy on the transmitter and from the MAX485 on the receiver from 3.3v to 5v, by adding 3.4v to it, but that doesn't mean that there's never gonna be a 0? How does this works? Are my schematics wrong? Isn't also 6.7v (3.3+3.4) an excess of voltage?
(Sorry if the schematics are messy)
For what I understand the input signal on the transmitter and the output signal on the receiver are tied to the center of a voltage divider (5v-47K on one side, 100K-GND on the other). Paul explains on the transmitter's OSH Park page that the output of the receiver outputs a 5v signal, so I think those voltage dividers are there to step up the signal from the Teensy on the transmitter and from the MAX485 on the receiver from 3.3v to 5v, by adding 3.4v to it, but that doesn't mean that there's never gonna be a 0? How does this works? Are my schematics wrong? Isn't also 6.7v (3.3+3.4) an excess of voltage?