Hey everyone, I'd appreciate a bit of help with a circuit I'm trying to design. Please keep things fairly simple as I'm not a pro, merely a hobbyist.
The goal: 8 way switching between the in/outputs of PCBS, including power supply lines and audio lines. If any of you are familiar with arcade cabinets, I am trying to design my own 8 way switching circuit for JAMMA boards. (The remote control solution available on ebay is just not to my taste)
A bit of scope to those who may not know much about arcade boards:
The JAMMA standard is an universal pinout of 2x28 pins on a PCB edge connector, carrying all input/output signals as well as power connections.
What I'm looking to switch:
Switches that go to joysticks/buttons are pulled down to ground when activated.
Monitor RGB and sync signals
Unamplified audio signals.
+12v, +5v (High current, can be up to 10 amps or more on occasion), +5v, Common GND
My idea:
I'm planning to use 27F251 8 way multiplexers to select which of the 8 boards' data lines get sent to the output connector (that goes to the monitor, joys, etc). about 40 of these would be needed (I do not need all the pins of a jamma connector as some are just keys or NC, etc). These ICs would switch all logic level signals, including the unamplified mono.
For the power supply lines, 4051 analogue demuxers would be my choice at the moment, with the input pin tied high, and each output leading to a 2n4401/tip122 which would control -all- ground connections for a single PCB, effectively eliminating the need to use separate switching circuits for all three voltages.
Both mux and demux are controlled by three inputs, and all would be tied to three switches, the different combinations of which would effectively select the PCB to be connected to the monitor/amp etc.
I know this circuit would be rather large, but I can get the 40pcs of 27f251 for about $2, and the 4051 is about 20 cents.
Nevertheless:
-Does anyone have an idea to make this more simple whilst keeping cost down?
-Would power being applied to all 8 pcbs tax my powersupply even if ground is only applied to a single PCB effectively keeping the rest shut off?
-Could anyone enlighten me about the ower requirements of the vdd vss vee pins of the 4051? The datasheet I've found is an utter mess...
Thanks for all your input!
The goal: 8 way switching between the in/outputs of PCBS, including power supply lines and audio lines. If any of you are familiar with arcade cabinets, I am trying to design my own 8 way switching circuit for JAMMA boards. (The remote control solution available on ebay is just not to my taste)
A bit of scope to those who may not know much about arcade boards:
The JAMMA standard is an universal pinout of 2x28 pins on a PCB edge connector, carrying all input/output signals as well as power connections.
What I'm looking to switch:
Switches that go to joysticks/buttons are pulled down to ground when activated.
Monitor RGB and sync signals
Unamplified audio signals.
+12v, +5v (High current, can be up to 10 amps or more on occasion), +5v, Common GND
My idea:
I'm planning to use 27F251 8 way multiplexers to select which of the 8 boards' data lines get sent to the output connector (that goes to the monitor, joys, etc). about 40 of these would be needed (I do not need all the pins of a jamma connector as some are just keys or NC, etc). These ICs would switch all logic level signals, including the unamplified mono.
For the power supply lines, 4051 analogue demuxers would be my choice at the moment, with the input pin tied high, and each output leading to a 2n4401/tip122 which would control -all- ground connections for a single PCB, effectively eliminating the need to use separate switching circuits for all three voltages.
Both mux and demux are controlled by three inputs, and all would be tied to three switches, the different combinations of which would effectively select the PCB to be connected to the monitor/amp etc.
I know this circuit would be rather large, but I can get the 40pcs of 27f251 for about $2, and the 4051 is about 20 cents.
Nevertheless:
-Does anyone have an idea to make this more simple whilst keeping cost down?
-Would power being applied to all 8 pcbs tax my powersupply even if ground is only applied to a single PCB effectively keeping the rest shut off?
-Could anyone enlighten me about the ower requirements of the vdd vss vee pins of the 4051? The datasheet I've found is an utter mess...
Thanks for all your input!
