Electronic – FPC cable contacts. Bottom vs Top and Bottom

connectordatasheetfpcpcb

I would like to design custom FPC cables as extensions of my flex pcb that will connect to this connector of another PCB.

My question is about the Connector/Contact type. In the digikey page it mentions "Contacts, Top and Bottom" compared for example to this connector where it just says "Contacts, Top".

My questions are:

1) what is the difference between the two types?

2) In designing the FPC cable for the first connector according to the datasheet
(see image below) do I assume that the contact between the FPC cable and the connector happens in the top side or the bottom side of the connector? The reason for the question is that it will determine if the FPC cable will be designed in the top or bottom layer of the flex pcb.

FPC footprint guide from datasheet

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Best Answer

The description is basically telling you which side the metallic contacts on the connector are located.

  • Contacts Top - means that the pads on your FPC need to be facing towards the top of the connector
  • Contacts Bottom - means the opposite, that the pads on the FPC face downwards
  • Contacts Top, Bottom - means literally both, there are contacts on both sides, so you can connect either way up.

In the case of the connector you are interested in (Datasheet), the terminals in the connector contact both the top and bottom sides of the FPC, which means that you can place the pads on your FPC on either side - it is up to you which one you choose.