Personal View site logo
Make sure to join PV on Telegram or Facebook! Perfect to keep up with community on your smartphone.
Please, support PV!
It allows to keep PV going, with more focus towards AI, but keeping be one of the few truly independent places.
Voltage Step Down Module
  • Vitaliy_KiselevVitaliy_Kiselev

    image

    • Input voltage: 4~40V;
    • Output voltage: 1.5~35V (adjustable);
    • Max output current: 3A
    • Voltage step down converter

    http://www.dealextreme.com/p/mini-dc-4-40v-to-dc-1-5-35v-voltage-step-down-transformer-module-142488

  • 27 Replies sorted by
  • jakerockwelljakerockwell

    I have a bunch of these 14.8v batteries: http://www.all-battery.com/TenergyLi-Ion18650_14.8V13000mAhBatteryPackPCBandConnector-31047-02.aspx

    Can I use this step down module to go from 14.8v to 7.2V?

    How about to go from 14.8v to 12v for a Black-Magic camera converter? http://www.blackmagicdesign.com/products/atemconverters/

  • Alfi666Alfi666

    @bangkng: Original batery does have a chip.. that's why 7.2V is enough... for external power you need 8.4 at least... And as Vitaliy said, you can have even 20 of those batteries in parallel and run the GH2 for 20 days in row ;)

  • MarcusMarcus

    step-up from a 7.2V battery grip to 9V for powering the GH2 and in a smaller form factor would be more useful.

  • bangkngbangkng

    @vitaliy_kiselev you are saying it doesn't matter what my batter capacity is as long as my voltage is in the right range it'll work? so that means i can have 10 of these batteries in parallel then attach a step up converter and i am good to go?

  • Vitaliy_KiselevVitaliy_Kiselev

    my concern is whether or not 8000mAh is too much for the gh2 to handle.

    LOL. 8000mAh together with voltage defines battery capacity. While original battery can be less, external DC power must be more for GH2.

  • bangkngbangkng

    @alfi666 but gh2 original battery is only 7.2v. my concern is whether or not 8000mAh is too much for the gh2 to handle. it's not going to melt my gh2 right?

  • Alfi666Alfi666

    @bangkng 7.4V is not enough... you need step-up

  • fehafeha

    here is my video tutorial :

  • bangkngbangkng

    hi guys, i have a sony f970 battery and it's 7.4v 8000mAh. do i need to use a step up/down module to connect the battery to my gh2 or can i just connect it directly?

  • Alfi666Alfi666

    @kavadni : maybe worth to mention that I've used a 3rd party battery which I took apart.... so I can't comment on the insides of original coupler.

    And since I'm using a step-up converter that was a bit too long to fit into battery, I had to cut down the PCB partially and relocate the capacitor to side.

  • kavadnikavadni

    @alfie666 That looks great, I've ordered a couple of these .. I'll be in touch to find out where the snap lugs are on the DCC-8

  • Alfi666Alfi666

    @kavadni : If you're using standard 3 pin voltage regulator, then you are wasting your battery capacity, as those regulators are quite unefficient and they generate heat. These DC-DC converters are much more efficient. That's how mine is stucked inside a GH2 battery :)

    photo (5).JPG
    598 x 800 - 143K
  • alcomposeralcomposer

    @Alfi666

    Good job!

  • kavadnikavadni

    Nasty phone pic .. this is what mine looks look .. Standard 3 pin voltage regulator .. couple of caps and a few resistors .. mine outputs 9volts .. and accepts any voltage from 9v to 30V

    I used a $5 kit from Altronics .. electronic hobby store .. liken to RS Components .. Tandy

    For $4.20 it looks smaller, I'll get one .. and a smaller box

    IMAG0007.jpg
    2048 x 1360 - 360K
  • fatpigfatpig

    very nice!

  • Alfi666Alfi666

    You just need a voltmeter with which you will adjust it very precisely... it couldn't be done with DIP switches. Everyone tinkering with electronics must have a voltmeter, so this is very easy solution.

    I personally use a similar step-up module directly built in into the battery which goes into GH2 - so to the outgoing wire I can connect standard 7.4V Sony L battery.

    So far without any issues, so I can recommend :)

  • dishedishe

    you mean that little screw? Yikes, there had BETTER be some dipswitches on the other side of that blue thing!

  • Vitaliy_KiselevVitaliy_Kiselev

    Look at blue thing :-) It is adjustable.

  • dishedishe

    Interesting... this could go nicely in a little plastic housing coming off the wire from a 12v battery. I wonder how the voltage is set? Are there dipswitches hidden out of view?

  • Vitaliy_KiselevVitaliy_Kiselev

    Is this the kind that just gives off the extra energy in heat?

    No, of course. They are quite efficient.

  • dishedishe

    Is this the kind that just gives off the extra energy in heat? Or is it one of the energy efficient models that actually converts?

  • alcomposeralcomposer

    @kankala. ($4 for the whole thing- not only the IC etc). The IC even has overheating protection!

    Ahh... Zenner - those are those things that create white smoke when you plug in the wrong power supply to a HDD? Save the drive but fry the diode- shunt to earth.

  • kankalakankala

    Zenner diodes "fuse" for voltage. They are made to open at different voltages, alas to provide proper protection (i just used 3 words that start with pro :-), you would need one that can withstand the max output current provided by the supply module without exploding. that may require a heatsink on the diode, and it will probably fry the supply module, but that's the idea, better it than the GH2

    @alcomposer usually it's the transformer/coil that is present in such circuits that's the expensive one, not the IC itself, at least that's what i remember

  • alcomposeralcomposer

    The 'brains' of this Buck style step-down converter is the Texas Instruments LM2596:

    http://www.ti.com/lit/ds/symlink/lm2596.pdf

    Don't be fooled by its 'cheep as chips' price... $4 is a very expensive component- considering they make millions of these units.

    I believe that from reading the PDF the LM2596 features 'many' self protection circuits including an emergency shut down mode.

    Remember that these can get hot- so if you are going to be 'retrofitting' them to 14.8v V-locks or whatever- remember to try to keep them coolish, (heat sink from your local electrical shop).

    To answer @Sangye... I think that fuses work on Amps not Volts. So you could only protect the device if for example there is a short circuit and draws stupid amounts of Amps.

    Otherwise I think you may need some 'other' device in chain.

  • SangyeSangye

    I know very little about circuitry, but would it be possible to wire a fuse that blows if the voltage exceeds 10v, after the step down module? That way if anything goes wrong with the module, it still won't fry the camera body.

Add a Comment