Author Topic: 9V to 12V best way  (Read 945 times)

Amitay3333

9V to 12V best way
« on: July 10, 2022, 05:47:46 PM »
What the best way to convert 9V to 12V?
I mean Forget the 78L12 regulator, what the best small compact charge pump circuit I can use?(for my deluxe mistress clone)
Thinking more LT1054 less ICL7660s

MikeA

Re: 9V to 12V best way
« Reply #1 on: July 10, 2022, 10:43:00 PM »
Simplest solution?  A Traco TEC 2-0912, +9V in, +12V regulated out, up to 167 mA.  Not cheap ($10) but you gets what you pays for.  You can also configure a TI LT-1054 for regulated +9V to +12V conversion up to ~100 mA with the addition of an op amp, using Figure 28 from the LT1054 datasheet plus some modifications detailed in this thread:  https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/878723/lt1054-positive-voltage-doubler-with-regulation/3279191


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DrAlx

Re: 9V to 12V best way
« Reply #2 on: July 11, 2022, 11:51:29 AM »
I have used a DC-DC MT3608 boost board (common and cheap on eBay) for my EM clone but I have onboard 78L12 regulator on the clone.
A few things to bear in mind with this approach...

1) The board switches at over 1MHz and you have to keep it away from audio sections of your PCB.
    I wrap the board in foil to provide shielding. You can always use the boost-board to make an external dongle to give boosted supply for other pedals.

2) The RF section of the EM (i.e. VCO) will affect the RF circuitry on the boost board itself, leading to noise in the audio.
    That can be solved by adding a 100nF ceramic cap on the boost board directly between its VOUT+ and VOUT- pads.
    So my overall supply is as follows with the 100nF soldered on the boost board, and the rest on the PCB.

Code: [Select]
   BOOST_BOARD_VOUT+ ----+--- 47R ---+--- 78L12_Input
                         |           |
                       100nF       100uF
                         |           |
   BOOST_BOARD_VOUT- ----+-----------+--- Gnd on PCB

imJonWain

Re: 9V to 12V best way
« Reply #3 on: July 11, 2022, 09:01:46 PM »
Do you really need 12V?
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TFRelectronics

merlinb

Re: 9V to 12V best way
« Reply #4 on: July 12, 2022, 04:30:55 AM »
Do you really need 12V?
Surely not?

Amitay3333

Re: 9V to 12V best way
« Reply #5 on: July 12, 2022, 05:48:33 AM »
Do you really need 12V?

Well I don't need, it's the pedal that demands it😜

amz-fx

Re: 9V to 12V best way
« Reply #6 on: July 12, 2022, 11:20:04 AM »
I did a couple of projects with the Recom isolated power modules:

http://www.muzique.com/lab/24v_iso.htm

The modules are available in several output voltages, though you can trim them to other output values by the jumper that I put on the schematic.

Best regards, Jack

GGBB

Re: 9V to 12V best way
« Reply #7 on: July 15, 2022, 09:57:59 AM »
Maybe have a look at something like the LM2577 https://www.ti.com/product/LM2577.
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Amitay3333

Re: 9V to 12V best way
« Reply #8 on: July 23, 2022, 05:44:43 PM »
Simplest solution?  A Traco TEC 2-0912, +9V in, +12V regulated out, up to 167 mA.  Not cheap ($10) but you gets what you pays for.  You can also configure a TI LT-1054 for regulated +9V to +12V conversion up to ~100 mA with the addition of an op amp, using Figure 28 from the LT1054 datasheet plus some modifications detailed in this thread:  https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/878723/lt1054-positive-voltage-doubler-with-regulation/3279191



Thanks MikeA!
I like the idea of the dc converter, I'll think about it, I want to check also MPD and Recom stuff...
after a little search I found the new "xo deluxe mistress"
Uses icl7660s converter and that seems to me a little wired since I know the icl7660s current capability is up to 10MA which is pretty low I guess, also I didn't find the right LT1054 schematic for voltage doubler maybe someone can help me with that, I also understand the lt1054 capability is up to 50MA as a voltage doubler(I saw couple of schematics online)
« Last Edit: July 23, 2022, 05:47:17 PM by Amitay3333 »

GGBB

Re: 9V to 12V best way
« Reply #9 on: July 23, 2022, 09:37:29 PM »
If current is a concern - the LM2577-12 can easily deliver well over 1A of regulated 12V from a 9V input if you need it - and the circuit is super simple although it requires a small inductor. Here's the circuit for 5V->12V - component values would vary for 9V input, and output current requirements would dictate the inductor choice:


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amptramp

Re: 9V to 12V best way
« Reply #10 on: July 24, 2022, 08:23:45 AM »
Are you sure you need anything more than this?



One of these is used on an RF doorbell I just bought.  It is the diameter of a AAA battery but about 60% of the length of a AAA battery at 28.2 mm long by 10.0 mm diameter.  These are usually rated at 55 mAh.  You could make your own with coin cells and a plastic cylinder to put them in.  Alternatively, you could just use three lithium cells and some versions would get you 13.8 volts and some would be rechargeable.  No RF noise!

PRR

Re: 9V to 12V best way
« Reply #11 on: July 24, 2022, 02:54:08 PM »
Are you sure you need anything more than this?....  These are usually rated at 55 mAh. ...

The Deluxe Mistress is 9 op-amps? Could be 27mA right there. 55mA battery implies 2 hour service. A 2-hour rate is a heavy discharge and capacity will reduce to ~~29mAh (@6V, which we can't use). And at ~~~$1.50 each that's good value but maybe >$1.50/Hour is more than I am worth?

Yes, major redesign for lower consumption would work. The 9 opamps could be <<1mA types and get the total budget down to 3mA (a bit more at short delay).
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Amitay3333

Re: 9V to 12V best way
« Reply #12 on: July 31, 2022, 01:53:18 PM »
Simplest solution?  A Traco TEC 2-0912, +9V in, +12V regulated out, up to 167 mA.  Not cheap ($10) but you gets what you pays for.  You can also configure a TI LT-1054 for regulated +9V to +12V conversion up to ~100 mA with the addition of an op amp, using Figure 28 from the LT1054 datasheet plus some modifications detailed in this thread:  https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/878723/lt1054-positive-voltage-doubler-with-regulation/3279191



Thanks MikeA!
I like the idea of the dc converter, I'll think about it, I want to check also MPD and Recom stuff...
after a little search I found the new "xo deluxe mistress"
Uses icl7660s converter and that seems to me a little wired since I know the icl7660s current capability is up to 10MA which is pretty low I guess, also I didn't find the right LT1054 schematic for voltage doubler maybe someone can help me with that, I also understand the lt1054 capability is up to 50MA as a voltage doubler(I saw couple of schematics online)
I didn't understand yet why the mistress uses icl7660s and what schematic is the right one for the lt1054 can someone help me with that?
« Last Edit: July 31, 2022, 01:54:51 PM by Amitay3333 »

Amitay3333

Re: 9V to 12V best way
« Reply #13 on: August 03, 2022, 02:18:46 PM »
https://www.arrow.com/en/reference-designs/typical-application-using-lt1054is8-positive-doubler/15359ab8d7c88edc29b1baf18edbd2c4
Is it legit? I try to found the smallest possible schematic for LT1054 voltage doubler...

MikeA

Re: 9V to 12V best way
« Reply #14 on: August 03, 2022, 03:40:53 PM »
https://www.arrow.com/en/reference-designs/typical-application-using-lt1054is8-positive-doubler/15359ab8d7c88edc29b1baf18edbd2c4
Is it legit? I try to found the smallest possible schematic for LT1054 voltage doubler...
Yes, this is taken from the data sheet and will work as a voltage doubler.  Actual output voltage is a bit less than double, something like 2x the input voltage less 2 diode drops and the internal voltage loss of the charge pump.  So +9V in will give you around +16V out, depending on the current and your choice of diodes.
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Rob Strand

Re: 9V to 12V best way
« Reply #16 on: August 03, 2022, 07:25:05 PM »
https://www.google.com/search?q=lt1054+voltage+doubler&oq=lt&aqs=chrome.2.69i57j69i60j69i59j35i39j0i512l4.1669j0j7&client=ms-android-samsung-gj-rev1&sourceid=chrome-mobile&ie=UTF-8#imgrc=ocwPjEzQs_xQbM
So I gues that though isn't legit?
Mike A already said it all!

Main points:
- voltage is less than double
- the output voltage drops under load.

You can see the doubler in the fig 20 of the manufacturer's datasheet,
https://www.ti.com/lit/ds/symlink/lt1054.pdf

Good idea to have a larger input cap.

You can scrape a little more output with Schottky diodes.
Larger caps can also help upto a point:
- The output cap (shown 100uF) sets the ripple.  That can help increase the effective output voltage
   as it raises the dips in the output waveform ripple.  The average output measurement by a DMM might
   not be affected so much.
- The transfer cap (shown 10uF) has a small effect on the output voltage.  However there's a point where the voltage drops in the device exceed any improvements in making the cap larger.
- The input cap (show 2uF) can raise the output voltage when you have high impedance supplies like old batteries
   It mainly helps prevent noise getting onto the ground lines.
« Last Edit: August 03, 2022, 08:28:08 PM by Rob Strand »
Send:     . .- .-. - .... / - --- / --. --- .-. -

amptramp

Re: 9V to 12V best way
« Reply #17 on: August 03, 2022, 09:41:00 PM »
There are boost regulators with the general flyback circuit topology and they are commonly used for low-wattage power since all of the energy to be delivered is stored in a magnetic element so it has size issues above a certain wattage (about 50 watts).  But for a low-power supply it has the advantage that when inductor current turns on, the current ramps up, causing little interference whereas a voltage doubler circuit has a step function of current both during charge and transfer of charge.  The voltage peak in a flyback can be regulated and only the peak charging current switching to low current in the opposite direction causes noise.

Amitay3333

Re: 9V to 12V best way
« Reply #18 on: August 04, 2022, 04:27:53 AM »
Thanks a lot guys!!
I didn't see it right on the datasheet probably because I was tired...
Are you sure you need anything more than this?....  These are usually rated at 55 mAh. ...

The Deluxe Mistress is 9 op-amps? Could be 27mA right there. 55mA battery implies 2 hour service. A 2-hour rate is a heavy discharge and capacity will reduce to ~~29mAh (@6V, which we can't use). And at ~~~$1.50 each that's good value but maybe >$1.50/Hour is more than I am worth?

Yes, major redesign for lower consumption would work. The 9 opamps could be <<1mA types and get the total budget down to 3mA (a bit more at short delay).
I still didn't understand what have you said/ask(my english not perfect) what do you mean by "The Deluxe Mistress is 9 op-amps?"