Running an LM386, NE555, NE556, JRC4558, & PT2399 circuit sharing Power supply?

Started by Jasonmatthew911, March 14, 2012, 02:53:32 PM

Previous topic - Next topic

Jasonmatthew911

Hey guys, I was just wondering if a 9V Boss PSA-120 adapter with 500mA would be able to supply sufficient power to an oscillator synth project I'm working on, which involves powering 5 IC's (LM386, NE555, NE556, JRC4558, & PT2399)???....Also, do you think I have to worry about problems if these 5 IC's are all on the same Supply +V rail?...the power would first go into a 7809 Regulator, then a .1 Cap to GND, followed by an Electrolytic of 470uf - 1000uf to GND and then a 1N4001 Diode to GND, for the PT2399 I would add the 7805 Regulator so it doesn't get more than 5V...Would I need something else to isolate the IC's from each other, or will these parts work fine?...Oh, and if I wanted to run this circuit on a 9V battery will that be enough, or would I have to parallel (2) 9V batteries so that my batteries will last a few hours and provide enough power to the 5 IC's??

Can anyone help me with my doubts about this?

frequencycentral

http://www.frequencycentral.co.uk/

Questo è il fiore del partigiano morto per la libertà!

CynicalMan

Your power supply has enough current to supply all of those chips, but the amount of filtering and isolation necessary would depend on the circuit. With oscillators, it's easy to get signal in the power line if you're not careful. What circuit(s) are you making?

This project would eat through batteries like popcorn. It would probably work, but not for long. Also, batteries in parallel are bad. If one has a higher voltage than the other, it will pass current through the other battery. This wastes charge and is potentially dangerous.

amptramp

If you have a 9-volt adapter, it will not run a 7809.  A 7809 needs about 11 volts minimum and 12 volts preferably to provide the dropout voltage necessary to generate a solid 9 volts.  Start with a 12-volt adapter and things will work better.

Jasonmatthew911

Quote from: CynicalMan on March 14, 2012, 03:06:20 PM
Your power supply has enough current to supply all of those chips, but the amount of filtering and isolation necessary would depend on the circuit. With oscillators, it's easy to get signal in the power line if you're not careful. What circuit(s) are you making?

This project would eat through batteries like popcorn. It would probably work, but not for long. Also, batteries in parallel are bad. If one has a higher voltage than the other, it will pass current through the other battery. This wastes charge and is potentially dangerous.

Thanks....Here it is:
    Basically I'm building an Atari Punk Console w/ 556 chip going into an Active Low-Pass Filter using the 4558 chip, then from the LPF it will go into 1 input of a passive ring mod using 2 transformers and 4 Germanium diodes, then into the other input of the Passive ring mod will be a 555 LFO, which I can also feed into the CV of the 556 APC...I will have a DPST switch to take the 555 LFO out of the circuit, like to turn the ring mod off or to feed an external instrument into the other input of the P. ring mod through an external jack, then the output of the ring mod will be pre-amplified with an LM386 circuit, not connecting pin 1 to pin 8 for minimal gain...Finally the LM386 will go to a DPDT switch to either go directly to output jack or directly into a Lo-fi Delay PT2399 circuit...And then just for fun I will add an arcade button killswitch...hehe

Let me know if you think all of that is gonna give me problems if they are sharing the same supply rail?....Would there be a difference between putting 1 large electrolytic Cap Vs. 5 large Caps for each chip so they can be close to the chip???...Could it help, or what do you think would help?

The reason I asked my original question was because I built a 2W mini amp with a 4558 Pre-amp going into an LM380 running both chips at 18V with heatsinks, and just those 2 chips were sharing the same supply rail, and besides the large Cap, extra .1 cap to GND I had a 10 ohm resistor in parallel with a ferrite bead to try and get rid of oscillation noises, but in the end it turned out I had to add a certain resistor at the input of the LM380, so I'm not really sure if sharing the supply rail had anything to do with that....Anyways, let me know what you guys think, now that you know what I'm trying to do...Thanks again

Jasonmatthew911

Quote from: amptramp on March 14, 2012, 08:28:01 PM
If you have a 9-volt adapter, it will not run a 7809.  A 7809 needs about 11 volts minimum and 12 volts preferably to provide the dropout voltage necessary to generate a solid 9 volts.  Start with a 12-volt adapter and things will work better.

I think I can leave the 7809 out...I was originally gonna put the 7809 because I was gonna use my 18V / 1A Dunlop adapter, just in case the Boss 9V with 500mA wasn't enough...I will only use the 7805 for the PT2399....I guess the 9V 1-Spot adapter is another good option to power this circuit since it can handle a little over 1A....My only concern now, is if I will have problems with these 5 chips sharing the same supply rail?

Thanks for the help...

Jasonmatthew911


Jasonmatthew911

Thanks....Here it is:
    Basically I'm building an Atari Punk Console w/ 556 chip going into an Active Low-Pass Filter using the 4558 chip, then from the LPF it will go into 1 input of a passive ring mod using 2 transformers and 4 Germanium diodes, then into the other input of the Passive ring mod will be a 555 LFO, which I can also feed into the CV of the 556 APC...I will have a DPST switch to take the 555 LFO out of the circuit, like to turn the ring mod off or to feed an external instrument into the other input of the P. ring mod through an external jack, then the output of the ring mod will be pre-amplified with an LM386 circuit, not connecting pin 1 to pin 8 for minimal gain...Finally the LM386 will go to a DPDT switch to either go directly to output jack or directly into a Lo-fi Delay PT2399 circuit...And then just for fun I will add an arcade button killswitch...hehe

Let me know if you think all of that is gonna give me problems if they are sharing the same supply rail?....Would there be a difference between putting 1 large electrolytic Cap Vs. 5 large Caps for each chip so they can be close to the chip???...Could it help, or what do you think would help?


The reason I asked my original question was because I built a 2W mini amp with a 4558 Pre-amp going into an LM380 running both chips at 18V with heatsinks, and just those 2 chips were sharing the same supply rail, and besides the large Cap, extra .1 cap to GND I had a 10 ohm resistor in parallel with a ferrite bead to try and get rid of oscillation noises, but in the end it turned out I had to add a certain resistor at the input of the LM380, so I'm not really sure if sharing the supply rail had anything to do with that....Anyways, let me know what you guys think, now that you know what I'm trying to do...Thanks again

Jasonmatthew911

Posting again just to see if anyone here can give me some more advice on the circuit I'm about to build... :icon_wink: :icon_cool:

CynicalMan

Relax, this isn't that fast a forum.

The 7805 should isolate the PT2399, so I wouldn't worry about that. Most of the other chips are all processing the same signal, so bleeding won't be a big issue. I'd probably put a separate power filter going to the LFO chip. 100 ohms and 100uF should do it. You'll need someone more experienced than me with big circuits to say if anything else is necessary, but I don't think you'll have many issues.

Jasonmatthew911

Quote from: CynicalMan on March 15, 2012, 11:50:40 AM
Relax, this isn't that fast a forum.

The 7805 should isolate the PT2399, so I wouldn't worry about that. Most of the other chips are all processing the same signal, so bleeding won't be a big issue. I'd probably put a separate power filter going to the LFO chip. 100 ohms and 100uF should do it. You'll need someone more experienced than me with big circuits to say if anything else is necessary, but I don't think you'll have many issues.

Haha, right on...Thanks for the help...I'll try to be more patient next time...I'll let you guys know how everything worked out when I'm done.