Author Topic: Missing inverter components identification  (Read 465 times)

0 Members and 1 Guest are viewing this topic.

Offline jerrykTopic starter

  • Regular Contributor
  • *
  • Posts: 228
  • Country: us
Missing inverter components identification
« on: January 14, 2024, 05:10:13 am »
I have a Magnum MS2012 inverter that had some components removed that I'm trying to identify.  I have attached some photos of an old board that I repaired that had these components intact if this helps.  Problem is they are ceramic caps with no labels and part of me thinks the cap values could be critical on the charge pump IC. Just afraid of screwing it up by experimenting.   Here are the datasheets for the two IC's.  AD8672 (missing cap C33) and the TC7662B (missing cap C35).  I attached a couple of crude partial schematics showing the caps location in the circuits.

It's actually a nice little inverter that I think it's only original problem was corrosion.  Then the owner dropped the cover on the main board.  Hence the missing components.

As always any help is appreciated.

Jerry

 

Offline fzabkar

  • Super Contributor
  • ***
  • Posts: 2735
  • Country: au
Re: Missing inverter components identification
« Reply #1 on: January 14, 2024, 08:47:02 pm »
The application examples in the TC7662B datasheet would suggest a value of 10uF for C35.

AD8672-A appears to be configured as a voltage follower. Is OUT A connected to +IN B of AD8672-B via a resistor? If so, what is the value of this resistor?
« Last Edit: January 14, 2024, 08:58:30 pm by fzabkar »
 
The following users thanked this post: jerryk

Offline jerrykTopic starter

  • Regular Contributor
  • *
  • Posts: 228
  • Country: us
Re: Missing inverter components identification
« Reply #2 on: January 14, 2024, 10:55:41 pm »
Here is a more complete schematic of the 8672.  I corrected the resistor value between OUT B and -IN B

Edit: I cannot find where the input to the voltage divider that feeds +IN B.  I don't know if that's needed or not.  Also sorry about the crude schematics above.  I screwed up Kicad on my laptop and took a moment to figure out what I did.

Jerry
« Last Edit: January 15, 2024, 07:20:35 pm by jerryk »
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf