Results 1 to 4 of 4

Thread: 78xx replacement

  1. #1
    Raw Wave SNOtwistR's Avatar
    Join Date
    Nov 2009
    Keswick,On Canada

    78xx replacement

    I have found this little gizmo and wondered if anyone has any past experience using them. They claim no heat @90% efficiency. SNO
    Name:  4670884.jpg
Views: 782
Size:  4.8 KB

  2. #2
    FLAC rray's Avatar
    Join Date
    Apr 2012
    SF Bay Area
    And you can run them with no load, and do not require filtering. Nice find, perfect for powering USB devices.

  3. #3
    Raw Wave
    Join Date
    Nov 2009
    Noting that the analogs (79xx, 79xx, 317 etc) usually only require a minimum load of 10mA - eg, a LED or 500 (560) Ohm resistor. For the 317, a 120 Ohm resistor is often chosen for its 1.2V reference resistor (it could be larger if a LED etc is used across its outputs).

    I saw SMPS equivalents to 3-terminal linears ages ago, but they were never that cheap! So x2 - nice find!

    As to no heat... well, the ~0.8W at full load should be fairly insignificant, and is far better than the equivalent 13W from a linear.
    And of course the usual SMPS theory where no filtering should be required for inputs or outputs (HF noise excepted). (Strange that high power amps need max voltage for max output eh?)

  4. #4
    Join Date
    May 2007
    I suggest you have a look at switching regulators, they tend to give the most eff. and low heat, lm2575 - 1 amp. and lm2576- 3 amp.. these regulators come as standard 5v/12v versions and also adjustable versions. i have been using these for many years now and have found them to be very reliable.

Similar Threads

  1. 700 TSV replacement
    By 2poor4mods in forum Xenarc Monitors Forum
    Replies: 1
    Last Post: 03-08-2010, 06:02 PM
  2. BMW e90 replacement bluetooth pc handfree replacement
    By dirtylarry in forum General MP3Car Discussion
    Replies: 2
    Last Post: 01-05-2010, 09:05 AM
  3. Replacement
    By joncole in forum General Hardware Discussion
    Replies: 2
    Last Post: 12-26-2007, 05:37 PM
  4. replacement TS?
    By theflygtiguy in forum LCD/Display
    Replies: 5
    Last Post: 09-12-2006, 07:17 AM
  5. t6 replacement
    By jure1873 in forum Power Supplies
    Replies: 7
    Last Post: 08-16-2002, 07:07 PM


Posting Permissions

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