GeorgeSpinner
Grand Master
I was looking for a way to add -5v to a cheap Chinese Supergun that didn't support -5v.
I came across the MC34063A - Voltage Reverser
The MC34063A costs anywhere from $2 - $5 per unit.
It takes input of 3.6v to 36v and outputs -1.5v to -36v.
It's rated for 1.5A but they recommend a lot less than that.
I assembled a JAMMA passthrough PCB and mounted the MC34063A to the JAMMA harness using 3M outdoor double sided tape.
I connected the MC34063A input to the 5v JAMMA (pin 3), GND to JAMMA GND (pin 1), and OUTPUT to the -5v JAMMA (pin 5).
I could have used JAMMA 12v (pin 6) but opted not to.
After it was wired, I used the potentiometer to adjust the output to as close to -5v as I could.
I did the adjustment with no PCB connected.
I tested it with a few PCBs and it seemed to work pretty well, but after 10 minutes (or so) the sound would cut out.
I was probably working the MC34063A too hard. It didn't feel hot or anything but that's my guess.
I added a small heatsink to the MC34063A's main chip and the working time went up to about 35-40 minutes.
This was starting to get good.
I added a 2nd MC34063A wired in parallel (Input (5v) - pin 4, GND - pin 2, Output (-5v) - pin 5).
I was able to use this configuration for several hours, without issue, without the use of any heatsinks.
I tested the -5v converter with Rastan Saga, Nastar Warrior, Double Dragon, Double Dragon II, and Vigilante.
This is the -5v converter I created using 2 MC34063A Voltage Reverser components:
This is the -5V converter running on my Double Dragon PCB:
This was a fun/easy little project that will get me some more use out of the cheap Chinese Supergun, or my Shogun MVS Supergun.
I usually use the Chinese Supergun with my PI2JAMMA or RGP-PI, but maybe I'll use it more often now. It actually works pretty well.
This could also be used to add -5v to a cabinet that doesn't have a -5v power supply.
I would probably just buy the correct power supply for my cabinet, but it's an option.
The only hiccup I had while doing this project was related to being sent the wrong part when I placed my original order.
tinkersphere.com sent me what they advertise as "MC34063 Positive to Negative Voltage Reverser" but it was in fact a Voltage Booster.
The PCB looks VERY similar to the Voltage Reverser I used, but the configuration of some of the components is different.
Component "D1" is horizontal on the Voltage Reverser.
Component "D1" is vertical on the Voltage Booster.
I emailed tinkersphere.com about this but they have ignored my email, so far.
I don't care about the money (and I'll keep the Voltage Boosters they sent me) but I don't want anyone else to end up getting the wrong item.
This is the item you DON'T want for this project:
I see how anyone could be confused, but when you are in the business of selling these components, you probably should know the difference.
Amazon was able to get me the right part for the same price.
I came across the MC34063A - Voltage Reverser
The MC34063A costs anywhere from $2 - $5 per unit.
It takes input of 3.6v to 36v and outputs -1.5v to -36v.
It's rated for 1.5A but they recommend a lot less than that.
I assembled a JAMMA passthrough PCB and mounted the MC34063A to the JAMMA harness using 3M outdoor double sided tape.
I connected the MC34063A input to the 5v JAMMA (pin 3), GND to JAMMA GND (pin 1), and OUTPUT to the -5v JAMMA (pin 5).
I could have used JAMMA 12v (pin 6) but opted not to.
After it was wired, I used the potentiometer to adjust the output to as close to -5v as I could.
I did the adjustment with no PCB connected.
I tested it with a few PCBs and it seemed to work pretty well, but after 10 minutes (or so) the sound would cut out.
I was probably working the MC34063A too hard. It didn't feel hot or anything but that's my guess.
I added a small heatsink to the MC34063A's main chip and the working time went up to about 35-40 minutes.
This was starting to get good.
I added a 2nd MC34063A wired in parallel (Input (5v) - pin 4, GND - pin 2, Output (-5v) - pin 5).
I was able to use this configuration for several hours, without issue, without the use of any heatsinks.
I tested the -5v converter with Rastan Saga, Nastar Warrior, Double Dragon, Double Dragon II, and Vigilante.
This is the -5v converter I created using 2 MC34063A Voltage Reverser components:
This is the -5V converter running on my Double Dragon PCB:
This was a fun/easy little project that will get me some more use out of the cheap Chinese Supergun, or my Shogun MVS Supergun.
I usually use the Chinese Supergun with my PI2JAMMA or RGP-PI, but maybe I'll use it more often now. It actually works pretty well.
This could also be used to add -5v to a cabinet that doesn't have a -5v power supply.
I would probably just buy the correct power supply for my cabinet, but it's an option.
The only hiccup I had while doing this project was related to being sent the wrong part when I placed my original order.
tinkersphere.com sent me what they advertise as "MC34063 Positive to Negative Voltage Reverser" but it was in fact a Voltage Booster.
The PCB looks VERY similar to the Voltage Reverser I used, but the configuration of some of the components is different.
Component "D1" is horizontal on the Voltage Reverser.
Component "D1" is vertical on the Voltage Booster.
I emailed tinkersphere.com about this but they have ignored my email, so far.
I don't care about the money (and I'll keep the Voltage Boosters they sent me) but I don't want anyone else to end up getting the wrong item.
This is the item you DON'T want for this project:
I see how anyone could be confused, but when you are in the business of selling these components, you probably should know the difference.
Amazon was able to get me the right part for the same price.
