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LiPo Loader-IC - how to solder a MSOP 10 package — Parallax Forums

LiPo Loader-IC - how to solder a MSOP 10 package

StefanL38StefanL38 Posts: 2,292
edited 2010-09-13 21:21 in General Discussion
Hello,

I want to build a LiPo Lithium-Polymer-Accu loader-circuit for a small single-cell (3.7V)

So far I have found the LTC1733 which seems very suitable as this IC
does all the loading-management. It seems to be only deliverable in a MSOP10-package.

Do I understand right that 0.5 BSC means pin-pitch 0,5mm?
That's pretty small for hobbyists. I have found a manufacturer for adapterboards. BUT - how can I solder this MSOP10 IC to the adapter-board???

I guess using a really small solder-iron will be very difficult. I don't plan
to use a lot of SMTs so I'm not gonna by a reflow-oven.

Can it still be done with hobbyists equipment?

Would a schmart-board
.5mm Pitch SMT Connector Board
be a solution?

Maybe somebody knows a chip or a circuit with a DIP-package that has
the same funcionality

Any kind of tips are very appreciated

best regards

Stefan

Comments

  • LeonLeon Posts: 7,620
    edited 2010-09-05 01:48
    Yes, the leads have 0.5 mm spacing. I don't have any problems soldering devices like that, even on home-made PCBs. I use a stereo microscope and a Metcal soldering system. The Schmart board should work.
  • TubularTubular Posts: 4,718
    edited 2010-09-05 03:38
    I think that particular Schmartboard only has one row of 0.5mm pads, as would be used with an LCD flat panel connector (FPC). You might be able to put two back to back to do what you want, but someone else must have a more suitable MSOP 0.5mm breakout.

    That particular chip needs its underbelly soldered to the pcb to dissipate the heat. And that (I think) really requires a custom pcb, otherwise the chip will limit its charging current.

    The MAX1555 is in a SOT23-5 pin package. 4 pins are on corners and so there's really just one tricky pin in the middle (pin 2). SOT23-5 breakout adapter boards are readily available. Charging current is less (280mA?) but unless you heatsink the LTC1733 it won't achieve 1.5A anyway
  • BenClarkBenClark Posts: 20
    edited 2010-09-13 08:34
    Does anyone know where to buy a MAX1555?
    Every where I look, they are either out of stock or you have to buy a minimum of 2500.

    Thanks
  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2010-09-13 17:52
    You migh want to look at this

    http://focus.ti.com/lit/ds/symlink/ucc3956.pdf


    or look at this

    These are in stock in a 8 SO PIN-PACKAGE

    http://www.mouser.com/ProductDetail/Maxim-IC/MAX1811ESA+/?qs=1THa7WoU59FxvQ%2fjYxmqcA%3d%3d

    http://datasheets.maxim-ic.com/en/ds/MAX1811.pdf
  • TubularTubular Posts: 4,718
    edited 2010-09-13 20:52
    You could also look at the MAX1551, which is very similar but has some difference with the status output (i think)
  • WBA ConsultingWBA Consulting Posts: 2,935
    edited 2010-09-13 21:21
    Sparkfun sells the MAX1555 but they are currently out of stock. They have a small board laid out nicely for $16.99 that is basically the reference design.

    I have thought of making the same circuit my PowerTwig formfactor so it would be easier for me to use 3.7v LiPos with my Propeller projects.
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