Dear Mr. Parallax - High Voltage Propeller Proto Board

idbruce

Hello Mr.Parallax And Everyone

Over the last three years I have been contending with voltage and power supply problems concerning peripherals controlled by Propeller Proto Boards, and I am sure that I am not the only one. Without going into too much detail concerning my problems, I would much rather discuss a solution.

I like the Proto Boards because of the prototyping area, the memory is already onboard, and the ability to easily program them with a PropPlug. Just plug in a power supply and a PropPlug, and you can start creating magic. I am a big fan of the Proto Boards!



However, in my case, the biggest drawback for the Propeller Proto Board has always been the power connector and the limitations of the LM1086-5.0 and the LM1086-3.3. Many of you already know me and you also know that I am more into the industrial application of the Propeller, as compared to hobby applications. Whereas the LM1086-5.0 and the LM1086-3.3 are perfect for hobby applications, this certainly is not true for industrial applications. And as time marches forward, I am certain that the Propeller will gain more and more use in industrial applications. So what I present here is a concept for a modified version of the Propeller Proto Board, let's call it the Industrial High Voltage Propeller Proto Board or the Propeller Proto Board HV. Without making too many changes to the original Proto Board design, I only recommend two changes for a new version.

1. Change the power connector to a 2-position wire screw clamp
2. Swap out the existing regulators for something like the LM2591HV-5.0 and LM2591HV-3.3

These two changes would allow the Propeller Proto Board to be powered up from a voltage source of up to 60VDC and eliminate the need to have ready access to 120VAC outlet for a smaller AC adapter.

I am certain that not everyone will agree, but for those of you who are into industrial applications, these small suggestions could make life a lot simpler for developing industrial applications for the Propeller chip.

Bruce

Leon

The market for such a board would be quite small, I'd have thought. Most industrial users who wanted something like that would simply design their own board.

StefanL38

Hi Bruce,

I second what Leon said. Industrial (EMV noise, high voltage, high current) environments need industrial designs. Take a look on the boards that BTX designed.

Anyway: I haven't looked up the regultarors datasheet. what I know about industrial designs (in europe) 24V is the standard voltage in industrial controls for valves and sensors of all kinds

I worked in a company who developed machines for the assembling of automobiles. When an extrapart needed 5V a suitable 5V powersupply is mounted inside the electric cabin.

For maintenance in non-vibrative environments a DIP40-chip is much easier to change than a protoboard.
You have to desolder a lot of wires or you have to solder wireconnectors on the protoboard. Then you have to replace the whole protoboard.
So what's the advantage of protoboards over a custom designed DIP40-board?

best regards
Stefan

idbruce

@Leon - If they are still in the prototype stage, it would be a perfect solution before contracting the creation of numerous boards. And I think the market maybe larger than you might think. The MakerBot projects are gaining traction here, and where you have stepper motor applications, there is almost always a desire for higher voltage.

Bruce

idbruce

@StefanL38

So what's the advantage of protoboards over a custom designed DIP40-board?

I also recommend a Propeller HV DIP Plus Kit

Leon

I simply designed a driver board with four big MOSFETs and two Micrel driver chips, which could be connected to a Proto board, when I prototyped a high-power system. I made the PCB at home.

idbruce

@Leon - But you had to provide two power sources instead of one

Bruce

Leon

That's OK for a prototype.

idbruce

@Leon - I should post some pics of the inside of my control panel for my CNC equipment, then you might understand my dilema. Perhaps my use of the word "industrial" was a little strong, maybe I should have used high voltage applications instead. For most of my projects, I have used Propeller Proto Boards or the Propeller DIP Plus Kit. I can make my own boards, but the Proto Board or the DIP kit almost always provided what I needed, except it always required two different power sources, (1) particularly just to power the propeller and another to power the equipment.

If I have 50VDC going into a cabinet to power my drivers, and the cabinet also contains Proto Board(s), I shouldn't need a seperate power source to feed the Proto Boards, I already have 50VDC in there

Bruce

idbruce

At the very least, the following setup makes this type of application much more difficult, and it is a real pain.

In fact, I have to do this very setup once again, and I ask myself why, which is the reason for this post.

Tubular

idbruce,

Have you seen this Parallax product?
There is also a discussion thread on it where some ideas you raise were discussed. It is a flexible kit, can save pins using serial driving mode, and you can choose SSR or Relays as output drivers.

In my opinion the change you request is easily handled by a DC-DC converter, there are some simple "7805 style" ones from Cui, Inc, and plenty of others (Newport NME series etc) for under $10. These are easily fitted to the proto board. But to be useful for industrial you really want some 24vdc inputs and outputs in addition to modifying the power supply, and then you may as well design it all to fit in a din rail enclosure.

idbruce

@Tubular - No, I had not seen that kit and it is pretty nice, so thanks for the link, however, to me it is a different solution to a different problem.

In my opinion the change you request is easily handled by a DC-DC converter

I agree, but then why buy a Proto Board, I could just use a DIP Plus kit or use Leon's suggestion and create a custom board. I like the Proto Board layout and setup, except for the power plug and regulators.

Bruce

graffix

I agree with Tubular, all our equipment uses PLC's and are quite happy with 12v logic.

http://www.aboutplcs.com/directlogic/
http://www.ab.com/

Cluso99

Sorry Bruce, you are trying to use a cheap board for an expensive solution. In your circumstances, as Leon said, you need a custom board.

The only thing your suggested options would do would be to increase the cost of the protoboards.

idbruce

It is sooooo very easy to say "That is a bad idea".

Bruce

JonnyMac

Sorry Bruce, you are trying to use a cheap board for an expensive solution.

Yep. It's silly to ask a manufacturer -- especially in these economic times -- to produce a low-potential product.

@Bruce: I designed the Propeller Platform to solve these kinds of problems. Nick offers them for sale in my *classic* version, and his shorter version that includes a microSD socket and space for an RTC. You could use ExpressPCB or DipTrace to create a daughter-board for the P/P that handles your needs. The ExpressPCB files are available for the Propeller Platform (classic) if you want to change the regulators, or you can put your own regulators on the daughter-board and route power to the Propeller through the connections.

You get a custom solution at a very reasonable cost.

prof_braino

Maybe this is the start of something interesting.

I mean, any application that needs a custom solution would need some set of common parts, can we describe a set of parts that would be common to any/many /most high voltage industrial applications? Something like an "industrial high voltage" proto board? Just a thought.

idbruce

Yep. It's silly to ask a manufacturer -- especially in these economic times -- to produce a low-potential product.

When was the last time that you researched CNC on the internet. It appears to be a pretty significant market to me.

EDIT: In fact, during hard economic times, many companies survive only because of their ability to diversify.

idbruce

@prof_braino

Just like I stated above, a 2-pos wire screw clamp and some different regulators.

JonnyMac

When was the last time that you researched CNC on the internet. It appears to be a pretty significant market to me.

When was the last time you researched anything or read a datasheet before posting here? (if you give snide, I'll give it back) You're asking for a high voltage prototyping board. Honestly, how many people would actually use it beyond you? And if they made the change you ask for on all boards then every customer is penalized for your specialty need.

I just did a big "Hollywood" job last week and instead of asking Parallax for a specialty board, I designed and built an add-on module for the Propeller Platform. Now, to me, anyway, "Hollywood" is a big market as lots of movies are made that require electronically controlled props, especially for LED control. But not to Parallax. Same for CNC; big to you because it's your focus. For Parallax it would likely be a waste of time to spend the resources that only a few people would actually use.

Trust me, it's harder than it looks. I've worked for manufacturers, including Parallax, and the process and resources for getting what ultimately ends up a seemingly simple product are not insignificant.

idbruce

@JonnyMac

instead of asking Parallax for a specialty board

I would not have even made this post if I did not believe that Parallax could profit from such a product. I am not asking Parallax to design a board specifically for me.

Bruce

idbruce

@JonnyMac

And if they made the change you ask for on all boards then every customer is penalized for your specialty need.

If you read earlier parts of the thread, I suggest a completely different board for high voltage applications.

JonnyMac

I would not have even made this post if I did not believe that Parallax could profit from such a product.

Well then, you're mistaken. And listen, I'm human, too; I often believe that what's good for me personally will be good for everyone else, espeically those that I can get to do hard work for me.

Since you dinged me on research, let me present you with some: You suggest changing the LM1086 with the LM2591 as if it's a 1-for-1 change. It's not. To start with, it's a different footprint which means the PCB has to be redesigned (time and $$$). Second is the cost delta. In 1000-unit buys from Digi-Key (using only for comparison) the 1086 is $1.15 and the 2591 is $2.86. Is Parallax just supposed to eat $1.71 per board for one customer? But it doesn't stop there. The switcher requires a choke and a diode -- again, more cost that will necessarily have to be pushed to the consumer.

Let me suggest that if you think CNC is such a great market you take the Propeller Platform ExpressPCB files and update them for HV input. If you're right, you could make some extra cash by selling the board to all those you think are just waiting for it. If you're wrong, you haven't spent a lot of money and you still have a board that works for you.

Mike Green

It's still an economically bad idea to make a special variation of the Protoboard or change the Protoboard's design for the case where someone wants to use a higher voltage supply. It's a bad idea anyway to use a linear regulator to supply 5V from a source much above 12V. There's too much power that has to be dissipated. The Protoboard is a general purpose board and may, very legitimately, have circuitry installed on it that may draw 500mA or even 1A. With a 12V power source, that's 3.5W or 7W that needs to be dissipated, way too much for a regulator with a minimal heatsink. A simple and pretty cheap solution would be to use a commercial switching regulator. Dimension Engineering makes a ready-to-go module for $25 that accepts inputs up to 60V and has an adjustable output anywhere between 2V and 14V at 1A that could be set to 6V to feed directly into the Protoboard's power input. I'm sure you could find cheaper ones or build your own.

idbruce

@JonnyMac

Since you dinged me of research, let me present you with some: You suggest changing the LM1086 with the LM2591 as if it's a 1-for-1 change. It's not. To start with, it's a different footprint which means the PCB has to be redesigned (time and $$$). Second is the cost delta. In 1000-unit buys from Digi-Key (using only for comparison) the 1086 is $1.15 and the 2591 is $2.86. Is Parallax just supposed to eat $1.71 per board for one customer? But it doesn't stop there. The switcher requires a choke and a diode -- again, more cost that will necessarily have to be pushed to the consumer.

I realize all this. I would have been happy to pay $200 for such a board for all the grief that it would have saved me.

I am not trying to get on your bad side, I just have my own opinion.

Bruce

JonnyMac

I would have been happy to pay $200 for such a board for all the grief that it would have saved me.

But you're the only one which is why -- as so many have pointed out -- this was a bad idea. Again, there are resources out the to help you make specialty boards, and as you know, there are people that will help you (with reasonable requests) here in the forums. Just scan through to see all the specialty PCBs that users create for their low-volume ideas.

idbruce

@Mike Green

A simple and pretty cheap solution would be to use a commercial switching regulator.

Mike thats what I am saying, provide a Proto Board that has a switching regulator instead of a linear one.

JonnyMac

Mike thats what I am saying, provide a Proto Board that has a switching regulator instead of a linear one.

Oi vey.... you may have an opinion but no grip on economic realities of small businesses like Parallax. To produce your desired product would impact sales of the other, and be low volume hence drive all prices higher. Bad idea for Parallax (higher prices which hurt customers and more products to inventory and support). Mike gave you a great idea which you now want to foist onto Parallax to save yourself a little sweat. That switcher module is just a switcher module hence can be used on anything, so there's a market for it.

idbruce

I have an exposure box, no need to get all upset Jon

idbruce

In fact, once those changes have been worked out, then modify the board a little more by adding 3 or 4 L6208 ICs and then you have a nice CNC controller.

Bruce

EDIT: And since it is Christmas, please add a MM74C922 keypad encoder

smbaker

From what I've seen, Parallax isn't beyond promoting the occasional specialty product. I recall one Nuts & Volts issue where they showcased a propeller-based audio board on the back page. I think it was the AP-16. That's quite a niche product to dedicate that much advertising space to. That board looks like it was designed (and manufactured?) by a third party, EFX-TEK.

I think something a step beyond just a high-voltage power-supply proto board would be handy. Throw in some high current drivers, and/or some opto-isolated IO and you could have a winner. It just might take 3rd party involvement to get it rolling, that's one good thing about the Prop, 3rd parties seem to be very adept at rolling out various platform boards.