i need some suggestion related to Selection of tactile switch. We know there two type of switch SMD and THT version. Which switch are better .when we need to use SMD and THT hole version Switch
I have used both switch for my application. I have faced Lot of SMD switches are failure. where as THT version works well in same application.kindly give some suggestion if any.
There are two sorts of failure here.
One is pure mechanical - the SMD devices are generally smaller and must clearly be more fragile. It very much depends on the mechanism you use to apply pressure to the button since it is never directly exposed to the user (except on prototyping modules such as Arduinox ). The TH switches are larger, some have long shafts to be directly operated through a housing.
The second failure mode relates to contact greases that some buttons use which degrade over time and absorb moisture, causing leakage currents. This is very much a quality matter, and indeed the overall problems with these buttons are basic quality matters.
In SMD switches also We have avilablity of height from 8 to 12.5mm But there 2 type gull wing and j lead type. If we use SMD switches they are more failure rates than THT version
I have used new switches in my end products. i have tested switches continuously more than 10k operation to check performance . they works well properly after that when subjected to actual feild condition they are failed.
i found most people prefer THT version than SMD version. To make process easier i preferred SMD version.
As u said i accept when i got switches they are open condition and corroded. so i took new switch but for SMD switches i found more failure rates. I have used recommend ckt from switch 12V 50mA
SMD switches can have a lower profile.
SMD switches soldered in an oven might have plastic damaged.
THD switches soldered by a hand iron might be less hurt by heating.
I straighten THD switch leads (take out all those bends) with needle nose pliers prior to soldering.
THD switches might better align to openings in panels etc.
THD switches leads can be cut with nippy cutters for removal.
Suggest you avoid submersion cleaning.