I downloaded 2 files from TI website
1) Swrc144a has CC2530EM Discrete schematic. See RF_P and RF_N pins 0724.CC2530EM_1_3_1_discrete_schematic.pdf
2) Swrc173c has CC2530EM w 2450BM15A0002 schematic. See RF_P and RF_N pins 4162.CC2530EM w 2450BM15A0002_1_0_schematic.pdf
As the file names, the only difference between these 2 files is in the RF portion, the swrc144a has discrete components while the swrc173c has 2450BM15A0002.
What are the advantages and disadvantages between these 2 circuits. Any functional difference?
I want to replace the external antenna with the internal antenna, any suggestion on how to do it? Which circuit I should use?
Thanks, Alice
Alice,
The two designs are equivalent. i.e. They get the RF signal to and from the antenna in the best possible way. The discrete component version of the RF balun is more tunable as the component values can be easily tweaked. It is a lot cheaper as well, as it is only made up of passives. On the flip side, you require RF expertise to be able to tune he RF network well. Also, this type of balun is more susceptible to ground plane depth variations (difference in depth of ground plane in reference design as compared to depth of ground plane in your board)
The chip balun on the other hand is less susceptible to ground plane depth variation, the matching is done for you. However, there is a cost associated with this. Also, if you have a small form factor, it is almost always better to use the chip balun
For antenna you can choose any 2.4 GHz antenna from the Antenna Selection Guide (http://www.ti.com/lit/an/swra161b/swra161b.pdf) and replace the SMA. Just make sure to add a shunt and series component at the feed point of the antenna so that you can tune the antenna on the board
---------------------------------------------------------------------------------------------------------Please click the Verify Answer button on this post if it answers your question.---------------------------------------------------------------------------------------------------------
Chatto,
I downloaded the CC2430DB Reference Design (swrr034.zip), there is a CADSTAR folder (attached here).
2605.Cadstar_files.zip
When I open the CC2430B_1_3 CADSTAR PCB file, I got a window pop up
“Part information is missing from the design. Do you wish to attempt to import it now? Your library must be set up correctly for this to work.”
I also attached the CC2430DB Schematic.
4024.CC2430DB_schematic_1_4.pdf
In page 4, there is a waveform connected RF_P & RF_N, what is that? The CC2530 doesn’t have the pin “TXRX_SWITCH”.
I assume CC2430DB used 2.4GHz Inverted F Antenna (DN007). http://www.ti.com/lit/swru120
For the shunt and series component at the feed point of the antenna, can I copy those in the CC2430 schematic L341 (L_1NB_0402_S) and C341 (C_5P6_0402_NP0_J_50)?
I also downloaded CC2530_ZNP CADSTAR files (swrr076.zip attached).
0116.swrr076.zip
When I open the CADSTAR PCB file, the antenna is missing. The antenna was shown in both Schematic and Layout pdf files (see attached)
3125.CC2530_ZNP_Layout.pdf
0172.CC2530_ZNP_Schematic.pdf
I assume CC2530_ZNP used small size 2.4 GHz PCB Antenna (AN043).
http://www-s.ti.com/sc/techlit/swra117
In page 2 of the attached CC2530_ZNP Schematic, there are shunt and series component at the feed point of the antenna C251 (C_1P8_0402_NP0_C_50) and L252 (L_2N0_0402_S), should I use this set of components?
If I want to use CC2530EM w 2450BM15A002 design w/ balun,
0083.CC2530EM w 2450BM15A0002_1_0_schematic.pdf
0842.CC2530EM w 2450BM15A0002_1_0_layout.pdf
can 2.4GHz Inverted F Antenna (DN007 http://www.ti.com/lit/swru120 ) fit into the existing board area?
Thanks