Selecting Power supply

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello to all,

Having trouble selecting the right power supply for the circuit in the attachment.

The attachment has two circuits , both of them belong to one project (audio spectrum Grafix)

Circuit (1) on the upper page is "Filter & switching" & the lower one is "Oscillator ,counter& decoder,VUled:

Both the Circuits are connected (control connection on both the circuits)

It would be very nice if any one can advise me , What kind of Power supply should i use for Circuit "1" ?
Do i use a separate Power supply for Circuit "2" ?

REGARDS,
LUBNAAN
 

Attachments

bertus

Joined Apr 5, 2008
20,173
Hello,

Is there no info on the site you found the schematics?

It looks like the "analog" schematic uses a dual powersupply for the opamps.
The "digital control" schematic uses a single powersupply +VCC.

The values of the voltages are not given.

Greetings,
Bertus
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

Is there no info on the site you found the schematics?

It looks like the "analog" schematic uses a dual powersupply for the opamps.
The "digital control" schematic uses a single powersupply +VCC.

The values of the voltages are not given.

Greetings,
Bertus
Following are the information i collected from the PDF Databook i found with the schematics.

OP AMPs in this circuit use dual power supply. Because we need 10 filters
so we use 2 ICs with 4 OP AMPs inside and 1 IC with 2 OP AMPs. ICs used
are TL084 (4 OP-AMPs) and TL082 (2 OP-AMPs).
The following is specification of two ICs:
- Working voltage: ±3 ¸ ±18V.
- Offset voltage Vos(max): 15mV.
- Input bias IB(max): 400pA.
- Bandwith: 3MHz.
- Maximum input voltage: ±30V.
- Increasing voltage speed: 13V/ms.
- Input resistance: >1012W.
- Consumption current(max): 5,6mA for TL082 and 11,2mA for
TL084.
Specification at condition of Vcc = ±15V, temperature T = 25oC.
 

bertus

Joined Apr 5, 2008
20,173
Hello,

I know the specs of the TL08X.
The 4017 and the 4069 will work from 5 to 15 volts.
The LM3914 will work from 9 to 25 volts.

I would take ± 12 Volts for the "analog" schematic and + 12 Volts for the "digital" part.

Is there no info given on the site where you got the schematics?

Greetings,
Bertus
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

I know the specs of the TL08X.
The 4017 and the 4069 will work from 5 to 15 volts.
The LM3914 will work from 9 to 25 volts.

I would take ± 12 Volts for the "analog" schematic and + 12 Volts for the "digital" part.

Is there no info given on the site where you got the schematics?

Greetings,
Bertus
To be honest , i was sent a PDF file from an old friend , it was especially meant for building of Audio spectrum Analyzer project , There is no such site where i found the schematic .
The schematic are all from the PDF sheet itself.

Regards
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Which of the following Transformers is recommended for the Analog schamatic ?

1) 0,5W 2x9V/28 mA
2)
1,5W 2x9V/85mA
3)
1,5W 2x12V/63mA
4) 2
,5W 2x9V/140mA
5) 2,5W 2x12V/105mA
6) 4
W 2x12V/170mA
7) 6W 2x6V/500mA
8) 6W 2x9V/330mA
9) 6W 2x9V/330mA

Before recommending the transformer, Please consider that , I will have to build a Rectifier circuit aswell & the capacitor will pump up the voltage .
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

You could try something like this using transformer 6:



Greetings,
Bertus
Thank you for your reply Bertus
OK, will proceed with your instructions.
I have attached a picture of my project , the Hardware is almost complete,
The big Circuit is ANALOG & the Smaller one is DIGITAL .
I'll be glad to receive Comments or advises if any.
 

Attachments

bertus

Joined Apr 5, 2008
20,173
Hello,

What powersupply are you going to use for the display / control part?
I think this needs to be more than 0.5 A (when all leds in one row are lighting) at the 12 Volts mentioned.

Greetings,
Bertus
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

What powersupply are you going to use for the display / control part?
I think this needs to be more than 0.5 A (when all leds in one row are lighting) at the 12 Volts mentioned.

Greetings,
Bertus
I was planning to use 12volt , 500mA Wall DC power supply.
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

Is the wall DC powersupply a stabelized one?

Greetings,
Bertus
Its just a Simple DC wall adapter that came along with my Panasonic Home Cordless Telephone.
I don't know if its Stabilized or no .

It has an output of 12V / 500mA
 

bertus

Joined Apr 5, 2008
20,173
Hello,

You could try.
Put the ground connections of both boards together.
This way you will not have a "floating" ground.

Bertus
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Thankyou,
Got your point .
Will keep Updated.
Hello

Just found a dual output Transformer in my Storeroom with the following parameters ,

Output Voltage : 2 x 12 Volt
Output Ampere : 3 Amps
Output Power 45 : watts

Is it appropriate to use the above Transformer for the analog circuit .
 

bertus

Joined Apr 5, 2008
20,173
Hello,

That is perhaps a bit overdone for the analog part.
There are only a couple of filters on that board.

Greetings,
Bertus
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

That is perhaps a bit overdone for the analog part.
There are only a couple of filters on that board.

Greetings,
Bertus
As a matter of fact, new Transformers over here in my City are very Expensive & I was trying to avoid spending extra buck by buying a new transformer for the analog circuit , So found this one , but it seems its too powerful & can be a risk factor .
 

bertus

Joined Apr 5, 2008
20,173
Hello,

You can use it.
The 7812 and 7912 will reduce the current to the board to about 1.5 A.
Do you have the datasheets of the stabelizers?
The transformer is powerfull enough to power both boards.
If you want to have a seperate power for the controller board you can use a second 7812 for it.

Greetings,
Bertus
 

Attachments

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Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

You can use it.
The 7812 and 7912 will reduce the current to the board to about 1.5 A.
Do you have the datasheets of the stabelizers?
The transformer is powerfull enough to power both boards.
If you want to have a seperate power for the controller board you can use a second 7812 for it.

Greetings,
Bertus
Hello,
Thank you for your reply & the Data-sheets.
I will go ahead & follow the instructions you posted & will keep you updated.
 

Thread Starter

lubnaan90

Joined Jan 13, 2010
198
Hello,

You could try something like this using transformer 6:



Greetings,
Bertus
Hello,

What is the use of 1N4001 Diode connected to the input & the output of both the IC,s & also the diodes which is grounding the Outputs , are those diodes necessary to be present on the circuit ?

Is it ok to use the circuit i have attached ?
 

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