Making a phone charger with my existing batteries

Discussion in 'General Electronics Chat' started by shredofme, May 16, 2013.

  1. shredofme

    Thread Starter New Member

    May 16, 2013
    1
    0
    Dear All,
    I have 4*18650 batteries, so my nominal output voltage is 4*3.7=14.8 DC
    I want to convert this voltage to a USB compatible (5.25 to 4.45 V and 1000 mAh)
    By definition I can use a buck (step-down) converter as it is a DC/DC converter. I looked at Texas Instrument website (following link) and ticked the specification required and here is what I have got:
    TPS51427
    TPS59650
    TPS51427A
    http://www.ti.com/paramsearch/docs/parametricsearch.tsp?family=analog&familyId=661&uiTemplateId=NODE_STRY_PGE_T&DCMP=hpa_pmp_tps4306x_en&HQS=regulators-pr
    Having looked at their datasheets they don’t match my problem (wrong components).
    Am I in a wrong route?
    Could you help me what to pick? Is a buck converter a good idea?
    Thanks
    Update: it seems that I had ticked Buck controller instead of buck converter.This time I ticked Buck/Boost converter and Step-Down (Buck converter) with my desired input and output voltage and got 210 components.
    Which one to pick again?
    Peripheral question: what is Vout2 (min) for?
    Thanks
     
  2. Dr.killjoy

    Well-Known Member

    Apr 28, 2013
    1,190
    156
    Instead of building one why don't you use an old car charger and work from there...
     
Loading...