LAUNCHXL-CC1350: Is the reference Sub 1GHz balun correct?

Dorian Levy

Part Number: LAUNCHXL-CC1350
Other Parts Discussed in Thread: CC1350

Hi,

I am working on a design using the CC1350 and am following the reference design. The reference schematic has more components (C17 and C18 I believe) than the physical Launchpad. Is the schematic correct? Is there a reference available for what is on the Launchpad, using less components? Here is the reference and a pic of the physical Launchpad.

over 8 years ago

0 Dorian Levy over 8 years ago

Intellectual 610 points

Sorry C17 and C18 was the 5xD design. It is C72 and C73 that are missing.

0 Sverre over 8 years ago in reply to Dorian Levy

TI__Mastermind 39860 points

I assume the schematic and the actual PCB revisions are not the same in your case.

The two shunt capacitors where added to reduce the effect of VCO pulling. Without the capacitors there will be poor TX modulation quality and the close-in phase noise will vary with frequency. The transient power when switching the PA on/off will also be high.

We recommend to use the two shunt capacitors in the sub-1 GHz path.

Sub-1 GHz

Sub-1 GHz forum

LAUNCHXL-CC1350: Is the reference Sub 1GHz balun correct?