Voltage Doubler Circuit stompbox - ICL7660 CMOS

Started by ANDYEFFECT, February 07, 2006, 04:52:01 AM

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ANDYEFFECT

 ICL7660 CMOS

How to apply " Voltage Doubler Circuit " in all the pedals for more headroom?

http://www.diystompboxes.com/pedals/vdbl.html


thanks

D Wagner

Andy,

You can't do this with all pedals.  Watch the power ratings of the IC's and capacitors in an exisitng circuit.  It is not uncommon to see a 10v electrolytic cap in a B*ss pedal.  It will likely fail if you put 18v through it.

You would need to make a small board for your circuit, and mount it somewhere in the box where it won't contact anything.  Then you would use the 18v out where your 9v battery lead used to go, and the ground is still the ground.  The 9v shown on the schematic is for reference, or if you have a bipolar power supply requirement.  (The 9v would then be your Vref., between 18v and ground.)

Pay attention to the note about shielding the input.  The MAX1044 will not have the whine problem, as it can be clocked above the audio signal frequency.  It is not much more than the ICL7660.

Derek



TheBigMan

You'd need to use the ICL7660S, which is higher rated and has the same frequency boost feature as the MAX1044.  There are stripboard layouts for doublers and bipolar/inverting supplies in my Layouts gallery.

ANDYEFFECT

Quote from: D Wagner on February 07, 2006, 07:28:33 AM
Andy,

You can't do this with all pedals.  Watch the power ratings of the IC's and capacitors in an exisitng circuit.  It is not uncommon to see a 10v electrolytic cap in a B*ss pedal.  It will likely fail if you put 18v through it.

You would need to make a small board for your circuit, and mount it somewhere in the box where it won't contact anything.  Then you would use the 18v out where your 9v battery lead used to go, and the ground is still the ground.  The 9v shown on the schematic is for reference, or if you have a bipolar power supply requirement.  (The 9v would then be your Vref., between 18v and ground.)

Pay attention to the note about shielding the input.  The MAX1044 will not have the whine problem, as it can be clocked above the audio signal frequency.  It is not much more than the ICL7660.

Derek




I will feed just some pedals, as bluesbraker, ts-808, maxon-808 and some booster. 
 
are the pins of ICL7660 the same of MAX1044?

D Wagner

Quote from: TheBigMan on February 07, 2006, 07:53:52 AM
You'd need to use the ICL7660S, which is higher rated and has the same frequency boost feature as the MAX1044.  There are stripboard layouts for doublers and bipolar/inverting supplies in my Layouts gallery.

Big Man,

Thank you for the tip about the ICL7660S.  I did not know about the "new and improved" version.  I like the price, as compared to the MAX1044!

Derek

Processaurus

Quote from: ANDYEFFECT on February 07, 2006, 12:34:15 PM
Quote from: D Wagner on February 07, 2006, 07:28:33 AM
Andy,

You can't do this with all pedals.  Watch the power ratings of the IC's and capacitors in an exisitng circuit.  It is not uncommon to see a 10v electrolytic cap in a B*ss pedal.  It will likely fail if you put 18v through it.

You would need to make a small board for your circuit, and mount it somewhere in the box where it won't contact anything.  Then you would use the 18v out where your 9v battery lead used to go, and the ground is still the ground.  The 9v shown on the schematic is for reference, or if you have a bipolar power supply requirement.  (The 9v would then be your Vref., between 18v and ground.)

Pay attention to the note about shielding the input.  The MAX1044 will not have the whine problem, as it can be clocked above the audio signal frequency.  It is not much more than the ICL7660.

Derek




I will feed just some pedals, as bluesbraker, ts-808, maxon-808 and some booster. 
 
are the pins of ICL7660 the same of MAX1044?

Hi, Derek is right, with some pedals that ask for a 9V supply you run the risk of breaking them by running them at too high a voltage, plus 3 out of the 4 pedals your plainning on doing this too don't need "headroom", because they're distortion boxes (that use diodes for clipping), and their clipping action limits the peak output to about a volt or two (basically "no headroom"), no matter how hard you play and how much voltage you're supplying it with.  The clipping voltage is independant of the power supply.

The only one I would think could benefit from a higher supply voltage is your booster, if its meant to be clean, because you could easily get an 18v peak to peak transient (which is huge, the typical guitar output is about 200mV) if you had the gain up high.

Some stompbox choruses and flangers that ask for a 9V supply can benefit from a 12v supply rather than the 9, to get better headroom (because they aren't meant to intentionally distort).

ANDYEFFECT

Quote from: Processaurus on February 07, 2006, 06:16:12 PM
Quote from: ANDYEFFECT on February 07, 2006, 12:34:15 PM
Quote from: D Wagner on February 07, 2006, 07:28:33 AM
Andy,

You can't do this with all pedals.  Watch the power ratings of the IC's and capacitors in an exisitng circuit.  It is not uncommon to see a 10v electrolytic cap in a B*ss pedal.  It will likely fail if you put 18v through it.

You would need to make a small board for your circuit, and mount it somewhere in the box where it won't contact anything.  Then you would use the 18v out where your 9v battery lead used to go, and the ground is still the ground.  The 9v shown on the schematic is for reference, or if you have a bipolar power supply requirement.  (The 9v would then be your Vref., between 18v and ground.)

Pay attention to the note about shielding the input.  The MAX1044 will not have the whine problem, as it can be clocked above the audio signal frequency.  It is not much more than the ICL7660.

Derek




I will feed just some pedals, as bluesbraker, ts-808, maxon-808 and some booster. 
 
are the pins of ICL7660 the same of MAX1044?

Hi, Derek is right, with some pedals that ask for a 9V supply you run the risk of breaking them by running them at too high a voltage, plus 3 out of the 4 pedals your plainning on doing this too don't need "headroom", because they're distortion boxes (that use diodes for clipping), and their clipping action limits the peak output to about a volt or two (basically "no headroom"), no matter how hard you play and how much voltage you're supplying it with.  The clipping voltage is independant of the power supply.

The only one I would think could benefit from a higher supply voltage is your booster, if its meant to be clean, because you could easily get an 18v peak to peak transient (which is huge, the typical guitar output is about 200mV) if you had the gain up high.

Some stompbox choruses and flangers that ask for a 9V supply can benefit from a 12v supply rather than the 9, to get better headroom (because they aren't meant to intentionally distort).



Yes my friend, do I know about that I will really want to use this project in the mini boutique amz booster and perhaps in the maxon od-808 that I will do, the ci´s ICL7660 and MAX1044 has the same pins?

TheBigMan

Yes, the ICL7660S and MAX1044 have the same pinout.  The 7660S is made by Intersil, datasheet is at their website.

ANDYEFFECT

Quote from: TheBigMan on February 08, 2006, 07:59:43 AM
Yes, the ICL7660S and MAX1044 have the same pinout.  The 7660S is made by Intersil, datasheet is at their website.

ok thanks

ANDYEFFECT

am I setting up a maxon od-808, placing this circuit to increase the voltage in the circuit him od-820 would be?