Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

What voltage should we see on Buck controller pins?

cupoftea

Advanced Member level 4
Joined
Jun 13, 2021
Messages
1,034
Helped
24
Reputation
48
Reaction score
44
Trophy points
48
Activity points
5,747
TPS57040 (buck controller) ….just soldered 10 of them to the board and none working. Suspect my solder technique, or dodgy chips. [Have done 10MSOPs before (months/years ago) though with success] Now going to just solder the lower divider resistor and the clock pin resistor and comp pin res and cap and SS cap, so don’t have to solder the entire buck converter to find out if I soldered the controller on well.

On the failed soldered units, got Soft start voltages of between 1v and 6v, and RT pin voltages of 200mv to 2v, comp pin voltage 200mv

Do you know what voltage we should see on these pins if we just solder the aforementioned components?

Also, the TPS57040Q i have here is package marked "5704Q"...and the datasheet doesnt say what the package marking should be.......do you know?........maybe i have the wrong chip here?

TPS57040
 
Last edited:

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
49,894
Helped
14,483
Reputation
29,236
Reaction score
13,391
Trophy points
1,393
Location
Bochum, Germany
Activity points
286,515
Also RT pin voltage is specified in the datasheet with about 0.5 V. Seeing 2 V suggests either incomplete ground connection or defective device.
 

c_mitra

Advanced Member level 5
Joined
Nov 13, 2012
Messages
3,800
Helped
929
Reputation
1,860
Reaction score
919
Trophy points
1,393
Activity points
29,962
Voltage readings may not be reliable if the device is not fully/ properly connected. If it is not properly connected, the voltage readings may not be indicative of any possible chip defect of malfunction.
 

LaTeX Commands Quick-Menu:

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top