Results 1 to 7 of 7

Thread: ARP : 7812 and LM 317 ???

Hybrid View

  1. #1
    Administrator T-1000 vikas's Avatar
    Join Date
    Feb 2004
    Location
    Delhi
    Posts
    1,922
    Blog Entries
    14

    Default ARP : 7812 and LM 317 ???

    Hi all

    I was building a basic cicuit and here are a few question

    Should i put in a battery charger ... simple lm 317 based ( Ni -cd and Mh ) ??? what do you say

    Also do you think putting in 7812 will be a good idea ( for motors ) ??? Or a simple 7805 is enough

  2. #2
    Senior Member T-1000
    Join Date
    Jun 2004
    Location
    Bombay/Mumbai
    Posts
    498

    Default

    Just clip in a 7805 for all control logic..

    The motors can be run externally...most of the time they do not need regulators...

  3. #3
    Senior Member T-1000
    Join Date
    Jun 2004
    Location
    Bombay/Mumbai
    Posts
    498

    Default

    Just a suggestion..
    wont it be good to have a regulator or supply unit..just like an SMPS..delivering voltages like 5V,6V,9V,12V..

    They can be routed to required boards from there

  4. #4

    Default 317...

    I think its a smart idea to put in a charger.... 317 or equivalent... have the batteries been decided ?

    With NiMH rechargeables.. its this ever going to fit into 1k ??

    It is'nt a good idea to add a 7812 for the motors though... linear regulators have huge Vce*I losses.... a Switching supply (or PWM) is better... although i dont get why a direct connection wont do... Is there feedback planned - i.e. is the motor circuit a closed loop?

  5. #5
    Administrator T-1000 vikas's Avatar
    Join Date
    Feb 2004
    Location
    Delhi
    Posts
    1,922
    Blog Entries
    14

    Default hmm

    ill drop 7812 but keep lm 317 .

    Ni cd - 8 battries cost abt rs 160 [ 800 mha ]

    Ni - MH - dunt know the price

    anyay if you intend to use the charger can charge both .

  6. #6
    Senior Member Cyborg
    Join Date
    Aug 2004
    Location
    Bangalore
    Posts
    173

    Default

    I bought 8 Samsung NiMH 2100mAH batteries a few days ago....cost me a whooping 900 Bucks + charger another 200 bucks. But i would say the performance was worth it.

    One thing I would like to point is that NiCd would get heated up if more than two toy dc motors are run...it boils down to a tradeoff between performance & cost.....
    Sumandeep Banerjee
    M.Tech, IIT Kharagpur,
    B.Tech, IIT Kharagpur,
    http://www.robotix.in

  7. #7
    Senior Member Cyborg
    Join Date
    Aug 2004
    Location
    Bangalore
    Posts
    173

    Default

    NiMH take arround 10 hrs to charge on 200mA standard charger ..... it's the other drawback
    Sumandeep Banerjee
    M.Tech, IIT Kharagpur,
    B.Tech, IIT Kharagpur,
    http://www.robotix.in

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •