Hi,
I have CC2531 USB Dongle rev 2.1. I have the following doubt regarding the balun mounted on this. As per the BOM list given in the reference design document (ti.com/litv/zip/swrr067), the balun is Johanson Technology, Inc.’s 2450BM15A0002 balun. Now:
1) According to Johanson website for this balun (http://www.johansontechnology.com/en/technical-notes/integrated-passives-rf-comp/2450bm15a0002-matched-balun-for-the-texas-instruments-cc2530-zigbee-transceiver.html), the pins on the balun should be connected as:
Pin 1 - Antenna
Pins 2,5,6 - Ground
Pins 3,4 - CC253X IC
2) However, when I look at the USB Dongle, I find the balun is connected as:
Pin 1 - Antenna
Pins 2,5 - Ground
Pin 3 - Ground through a cap
Pin 4,6 - CC2531 IC.
Why is there a difference in the two implementations? Is it possible that the balun placed on the CC2531 USB Dongle is NOT 2450BM15A0002? The balun on my dongle does not have any numbers/markings so it is not possible for me to figure out the part number exactly.
Can anyone please help me with this?
Thank you
Ricky
