Hi everyone.
I have a circuit that I built which contains a micro controller chip, a reed relay, and a diode.
I have a molex right-angle connector on the board which receives +5v and GND, from there, wires under the board send that 5V and GND to the micro controller chip. The GND also goes to the reed relay's GND pin, as well as the switch (input) of the relay, and finally the GND goes to J3 of the 50v step up driver board (schematic is below).
The micro controller chip then has an output pin which goes to the relay (to turn it ON). Then the output of the relay goes to J1 of the 50v step up driver board.
So basically the micro controller chip sets one of its pins HIGH, and that in turn passes ground through the reed relay, and shorts out J1 and J3 with ground on the micro controller board.
... The problem I am having is my 50v step up driver board is not working properly when things are hooked up this way. If I run a totally separate ground wire directly to the reed relay's switch input, then it works perfectly.. But for some reason, when I share GND between the micro controller and the 50v step up board, it no longer works.
To describe what I mean by "no longer works": The 50v driver board is basically firing a solenoid. And then the GND is shared between it and the micro controller, the solenoid "taps" like it's trying to fire.. but it can't quite do it...
Once I run a separate ground to the reed relay (or directly to the 50v board for that matter), then it works fine, and the coil energizes.
... So I am trying to understand why this is happening and how I can fix it. I hate having to give my circuit two paths to ground because that feels wonky and gross (and also is inconvenient). So I am wondering if somehow it's a matter of noise? Do I just need to get a big fat resistor and put that between ground and the reed relay?
Can anyone shed some light on this problem?
I have a circuit that I built which contains a micro controller chip, a reed relay, and a diode.
I have a molex right-angle connector on the board which receives +5v and GND, from there, wires under the board send that 5V and GND to the micro controller chip. The GND also goes to the reed relay's GND pin, as well as the switch (input) of the relay, and finally the GND goes to J3 of the 50v step up driver board (schematic is below).
The micro controller chip then has an output pin which goes to the relay (to turn it ON). Then the output of the relay goes to J1 of the 50v step up driver board.
So basically the micro controller chip sets one of its pins HIGH, and that in turn passes ground through the reed relay, and shorts out J1 and J3 with ground on the micro controller board.
... The problem I am having is my 50v step up driver board is not working properly when things are hooked up this way. If I run a totally separate ground wire directly to the reed relay's switch input, then it works perfectly.. But for some reason, when I share GND between the micro controller and the 50v step up board, it no longer works.
To describe what I mean by "no longer works": The 50v driver board is basically firing a solenoid. And then the GND is shared between it and the micro controller, the solenoid "taps" like it's trying to fire.. but it can't quite do it...
Once I run a separate ground to the reed relay (or directly to the 50v board for that matter), then it works fine, and the coil energizes.
... So I am trying to understand why this is happening and how I can fix it. I hate having to give my circuit two paths to ground because that feels wonky and gross (and also is inconvenient). So I am wondering if somehow it's a matter of noise? Do I just need to get a big fat resistor and put that between ground and the reed relay?
Can anyone shed some light on this problem?
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