ADC Problem with SMD Components

[mdvrajkot]

Hello,

I am working on a project, which uses the inbuilt ADC of the microcontroller MSP430. When used the through hole components, it works well but when used SMD components, it does not work. Though Both PCB having same schematic and the components with same rating. So what could be the problem ?

 

[tantalos]

Through hole components have bigger parasitic inductance, so you have to add inductors with smd components.
Seriously how can we help you not seeing the design. :roll:, using a crystal ball?

 

[KlausST]

Hi,

tanatlos is right.
To give you good assistance we need:
* schematic
* board layout
* maybe a picture of the board
* a detailed error description. "doesn´t work" is no description.
* informations like: Supply voltage, supply current, system clock, control signals (always behaviour/value of the THM board and the SMD board)

My first hint, if it is a hand soldered board: check every SMD pin for good solder joint.

Klaus

 

[doraemon]

Hello!

It sounds very suspicious. I've been using 430s for more than 10 years, and have never
experienced malfunction. And I don't see any technical reason that would cause ADC only
to fail. By the way, only ADC fails? Or (more likely) nothing works at all?
If nothing works, that's good! At least we are in a known situation. In this case, I would
guess you forgot to wire the test pin (which was not mandatory on older chips), you forgot
the VCORE capacitor or something like that.

Dora.