Brokenrecord
New Member
Hey Guys, so I just finished this schematic based around the aforementioned voltage regulator. Any suggestions/corrections?
Thanks
Thanks
120VAC Solenoid and 12V fan control
- Thread starter Brokenrecord
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After a quick look:
You need a 1 meg resistor from the mosfet gate to the picaxe output. Ditto with the other two regulator controllers.
The LM317 input capacitor is from Vin to Ground, not in series with power in. Make that correction to all of your .1uF bypass caps.
I do not understand your switching plan for programming the 08Ms, but it doesn't look doable. Suggest you use sockets and program the 08Ms off-board. Put a 10K resistor from serin to ground on all three chips.
You need a 1 meg resistor from the mosfet gate to the picaxe output. Ditto with the other two regulator controllers.
The LM317 input capacitor is from Vin to Ground, not in series with power in. Make that correction to all of your .1uF bypass caps.
I do not understand your switching plan for programming the 08Ms, but it doesn't look doable. Suggest you use sockets and program the 08Ms off-board. Put a 10K resistor from serin to ground on all three chips.
Brokenrecord
New Member
Thanks so far,
Here's a pdf with much more resolution than the bitmap
oh and i forgot to take out the switchable 08m label at the bottom sorry
Here's a pdf with much more resolution than the bitmap
oh and i forgot to take out the switchable 08m label at the bottom sorry
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You need to correct the bypass caps at the 08M +5 and the 28x +5.
R4,8,12 -- 10K will not give you 12V out -- only 11.25max.
why are serout tied together, and where does the loose wire go to?
In 5 & 6 are tied together -- therefore the buttons are tied together.
I suggest that you look at every single connection, especially on the 28x, and be sure that it makes sense to you. Look for duplicate connections, look for pins tied together that should not be tied together. To be safe, each pin that needs a 10K to ground needs a *separate* 10K to ground.
Good luck with your project.
R4,8,12 -- 10K will not give you 12V out -- only 11.25max.
why are serout tied together, and where does the loose wire go to?
In 5 & 6 are tied together -- therefore the buttons are tied together.
I suggest that you look at every single connection, especially on the 28x, and be sure that it makes sense to you. Look for duplicate connections, look for pins tied together that should not be tied together. To be safe, each pin that needs a 10K to ground needs a *separate* 10K to ground.
Good luck with your project.
Brokenrecord
New Member
Wapo,
What do you mean correct the bypass caps +5? Do you mean they should be 5uF? And I do realize that they will not give the full 12v output, however I was just following the diagram provided. From my understanding the LM317 is governed by the equation Vin - 3 = Vout anyways. And since I can't find a 15v source I'll just have to live with it.
Also I have one voltage regulator with 24v in, so to give me a close maximum output I put two resistors in parallel; 4.7K and 10K. Is that correct? And finally I tied the serial outs of the 08m's together so that each one could send they're data to in 7 of the 28X1. I'll be implementing a polling mechanism to acquire temperature data and store it in the eeprom. Does that make sense or is it even feasible?
What do you mean correct the bypass caps +5? Do you mean they should be 5uF? And I do realize that they will not give the full 12v output, however I was just following the diagram provided. From my understanding the LM317 is governed by the equation Vin - 3 = Vout anyways. And since I can't find a 15v source I'll just have to live with it.
Also I have one voltage regulator with 24v in, so to give me a close maximum output I put two resistors in parallel; 4.7K and 10K. Is that correct? And finally I tied the serial outs of the 08m's together so that each one could send they're data to in 7 of the 28X1. I'll be implementing a polling mechanism to acquire temperature data and store it in the eeprom. Does that make sense or is it even feasible?
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Bypass caps are installed *in parallel* with the chip, between +5 and ground, not in series as you have them depicted.Wapo,
What do you mean correct the bypass caps +5? Do you mean they should be 5uF? And I do realize that they will not give the full 12v output, however I was just following the diagram provided. From my understanding the LM317 is governed by the equation Vin - 3 = Vout anyways. And since I can't find a 15v source I'll just have to live with it.
Also I have one voltage regulator with 24v in, so to give me a close maximum output I put two resistors in parallel; 4.7K and 10K. Is that correct? And finally I tied the serial outs of the 08m's together so that each one could send they're data to in 7 of the 28X1. I'll be implementing a polling mechanism to acquire temperature data and store it in the eeprom. Does that make sense or is it even feasible?
Your understanding of the LM317 is incorrect, suggest you read the LM317 data sheet. It is not governed by the equation Vin minus 3. What you read here only helps to clarify what you learn by reading the data sheets.
You need to re-read BCJKiwi's explanation of the voltage regulator, and of the voltage divider controlling the mosfet gate. The resistor values are determined so that as the 08M reads a maximum of 5 volts, the LM317 will be delivering whatever maximum voltage you want. To deliver 10.75 volts to the adjust pin (12V minus 1.25V - read the lm317 data sheet to understand this) when the 08M reads 5 volts, your divider resistors would be 10K and 11.5K.
I would suggest you start by building a voltage-regulator & fan assembly first, then a temperature controlled voltage regulator & fan and write the code as you go along, and gradually expand the project while you learn how this stuff works. Your full project is very ambitious and should be addressed in building blocks if you are learning as you proceed. That's my recommendation. Good luck with it.