QUESTION

Question

Hello,

The antenna selector suggested using an A10192H based on my board shape and antenna location.

1) This is a 3 pin antenna from all the pictures, but the datasheet says "9. Schematic symbol and Pin definition The circuit symbol for the antenna is shown below. The antenna has 5 pins with only two as functional. All other pins are for mechanical strength."   I'm going to assume this is just a copy paste error.

2) Section 9 table shows pins 1,2 as Feed pins and pin 3 as a mechanical NC pin.  However sections 11.2 and 14 show schematics where pin 2 is a NC pin not a feed pin.  Which is correct?  Is pin 1 the ONLY Feed pin?

3) The Bottom side drawing does NOT show which pads are which pin #.  Is the single pad on the left pin 3?  Is the pad above the single pad pin 1 or pin 2? 

4) Section 12.1 states "Where possible the antenna should be clear of ground from both sides,"  I assume that means left and right of the antenna.  Question: How about the layers UNDER the antenna?  Should all ground be removed?

I think a layout file of the A10192H Evaluation Board would probably answer most of my questions.  Is is possible to provide a layout?  

Thank You

Paul

Answer 1

Hi Paul,

Here are my comments:

1. Yes, this is an error on the datasheet there are only 3 pins.
2. Pin 1 is the feeding pin so the transmission line will be connected to pin 1 only.
3. The single pad is pin 3, the top pad is pin 2 and the bottom pad is pin 1.
4. The Fusca antenna needs to be placed in the corner with minimum 2mm ground clearance on left/right side of the antenna depending which corner the antenna is implemented. The layers under the antenna + the 2mm clearance needs to be free of groundplane or metal. This is known as the clearance area.

I will also send you the layout file

Best regards,

Yu Kai Yeung