Solenoid driver

[KeepItSimpleStupid]

I kinda goofed in terms of what I wanted to say. Brain isn't working well.

I meant to say you can Matrix the solenoids using High and Low side drivers. Just google "high side driver" and "low side driver" and even "solenoid drivers".

You can also Matrix the switches. It doesn;t matter if it's one switch out of 88 (like the one example) or the keypad of 000A and 000B, they still get the job done. "C" might be clear. and "D" might be erase 1 digit. True, you may need a small display too, but that should be cheap too.
A 4x20-line serial module might work just fine.

e.g. you type 001 and it displays the name of the switch and the state. then you type A or B to change the state. Maybe E is reserved for Toggle and "F" is "leave as display" or it just times out.

Without doing selection, I'll just give you this https://www.nxp.com/products/interf...us-portfolio/i2c-general-purpose-i-o:MC_41850 to look at.

I2C is known as Inter IC Communications. It can be made long if necessary. You can't just hang any number of the same devices off the I2C bus. The addresses are assigned by Phillips. Some IC's have multiple available addresses. If you need more expanders, you need to expand the I2C bus.

My point is, you can make it cost-effective for 50 switches or 100 solenoids. I really don't think you want 50 switches?

I wanted to try to get you to understand one concept before moving on to another.

Concept 1 which is the most important is controlling 50 switches. You can matrix them and create the pulse in software.
Concept 2 is the state of the switch: A) FRAM or B) A physical switch
Concept 3: is how to activate said switch: A) A simple display and a keypad or B) Single switches like you envision
(50 switches are expensive vs a $10.00 USD keypad)

Concept 4: Display the State of the switch. Basically I have no idea what your planning here.
50 LED's?; Red/green? LEDS that the train sees? And to be weird: Some sort of positive train control where if the switch is wrong the train stops.

I like throwing stuff out no matter how silly it is, At this point we are brainstorming, so anything goes.

 

[spec]

Just a bit of information: typically the point coils have a resistance of 3.5 Ohms to 4 Ohms. **broken link removed**

spec

 

[chemelec]

Chemelec, I agree with you: your design is just the best and will be used on my layout; all here have contributed so much, and in the end a lot come out of here. This board has given me so much in terms of information, friendship, help, sociability and feedback.. I feel in debt to you all.
Your offer of a pcb I gladly accept, I appreciate it a lot but I would like to know how I can return the favour: pm me anytime, I gladly reply.
Have a good day,
Erik

Hi Erik, I Don't see a PM link?
Send me an Email.
chemelec at Hotmail.com

 

[KeepItSimpleStupid]

Chemelec: They are called Conversations. Click on a member name and then "Start a conversation". Try PM Erik.

 

[chemelec]

Chemelec: They are called Conversations. Click on a member name and then "Start a conversation". Try PM Erik.

Thanks, But either way, I would prefer him to Email me and include his Mailing Address.

 

[chemelec]

Erik, Here is what I came up with.

 

[alec_t]

Text says 'Preferably with center off''. Isn't centre off essential? If any one switch is held at the 'Left' or 'Right' position then no other switch will be able to trigger the monostable.

 

[chemelec]

YES that is what would occur.

 

[spec]

Nice circuit and layout too. Can I suggest that you increase the decoupling capacitor from 0.1uF to at least 1uF and perhaps drop the decoupling resistor from 100R to 10R.

spec

 

[alec_t]

If you want a turnout left/right indicator for use with a centre-off switch, perhaps you could make something like this (excuse my graphics) :-

A slider with an elongated aperture could provide a certain amount of 'lost motion' so that it remains in the last operated left/right state even when the switch returns to the centre position.

 

[spec]

An alternative is this (with an inverter transistor on the 555 trigger input) :

 

[chemelec]

Nice circuit and layout too. Can I suggest that you increase the decoupling capacitor from 0.1uF to at least 1uF and perhaps drop the decoupling resistor from 100R to 10R.

spec

The 100 Ohm resistor will be OK to supress any Spikes from the solenoids.
This is driving a Mosfet so Output current is almost nothing.
A Breadboard of this Circuit has been built and tested.

I had considered a 1uf or 10uf Tantalum, But he might have problems getting tantalums.
That .1 Will work Ok.

I am offering him the PCB for Free, Including the Postage Cost, just sending it in a Letter.

I Could supply him with the PCB and All Parts, Including up to 20, Center Off Switches, But than it becomes a Parcel.
Between the Higher Cost of Shipping and all the Parts, I Can't do that for Free.

 

[spec]

Wow- what a helpful and thoughtful person you are.

spec

 

[chemelec]

It is Either sell these parts, even at a Cheap price, or Thrown them in the Garbage in the near future.
I have well over $100,000 of new parts in Stock.

 

[spec]

$100K ! That's about the same value of stock as a small distributor- how come so much? What have you got?

spec

 

[chemelec]

$100K ! That's about the same value of stock as a small distributor- how come so much? What have you got?
spec

Previously, Prior to 1999, I was Designing and Manufacturing Electronic Equipment.
In 2002, I started my website and have supplied parts for all my projects, so more increase in stock.
It has been Fun, but all things come to an end sometime.
I have planned to shut it down on the Oct 16 2017, Its Renewal Date.

I live in a TINY Village, No one here to use these items.

 

[spec]

Ah, I understand- just had a look at chemelec.com. I remember looking at your site about a year ago, when I first joined ETO, and being amazed.

spec

PS: I think an entry here would be appropriate: https://www.electro-tech-online.com...climb-a-mountain-build-your-own-house.149182/

 

[spec]

I live in a TINY Village, No one here to use these items.

Have you thought about selling your stock on the net, say through your site, or on ebay?

I once got hold of a load of 74 TTL chips that were being junked at work.

I made a list and posted copies off to as many component brokers I could find. Nearly all made low bids, but one company must have had a customer who wanted the parts and made a very good offer. I made quite a packet on that deal. Mind you, it took me a while to sort the bits and put them in plastic tubes, which were also being dumped.

spec

 

[spec]

If you want a turnout left/right indicator for use with a centre-off switch, perhaps you could make something like this (excuse my graphics) :-
View attachment 101605
A slider with an elongated aperture could provide a certain amount of 'lost motion' so that it remains in the last operated left/right state even when the switch returns to the centre position.

Brilliant Alec,

I have thought of a few schemes but, none are as neat and simple as that.

spec

 

[chemelec]

I did unload some stock to a company in the USA. (mainly 24KV Diodes)
But didn't get much for them.

Problem these days is Shipping Costs and Customs Declarations to other countries.
Many Countries are cracking down on parts that don't meet ROHS Specifications.

I Have basically No Digital Parts, Except for the 4000 Series.
Basically just Linear electronic, Through hole Parts.