smd components selection

[cool.man]

Hi,
I am going to design a pcb in which most of the components will be smd.
I have searched on internet and found that there are many packages of each components like if i select resistor then there are list of available packages like 2020,2512,1210 etc for capacitors available packages are 2412,2318,2917 etc.
will anyone tell me about the crieteria of selecting components, also how do i seach those components?

 

[analogLow]

Hello-
>will anyone tell me about the crieteria of selecting components, also how do i seach those components?
Selecting the components depends on pcb area requirements, cost, and component performance. The first thing to do would be to find out the required component values you need. Also, you need to identify any other component requirements (e.g. type of capacitor or requirement that the capacitor ESR must be XXX ohms). Then you can start to search for the biggest and cheapest components that meet those requirements. If the parts are too big, then go for smaller. Smaller components cost more but the pcb will be smaller and thus will cost less.

If you need some general pcb help check out this:
**broken link removed**

Cheers,
analogLow