please i have three questions:
first, i read two silabs documents named AN369 and AN369_rev01. i found two top layouts slightly different as mentionned in the attached files. So why they are two versions. what's the best ?
Second, the value of C1 capacitor (connected between TX+ and TX-) is not specified, just it's written non-pop.
Third, i bought an si4010 keyfob dev board, the L1 inductor and C1 (as shown in the attached file transmetteur_V1) are replaced by a meander inductor. the Vcc is placed in the middle of this meander inductor. the other parts of the meander is connected in Tx+ and TX-. so this configuration is different also from the two above configurations. so which ones is the best?
I've attached two design packs for the Si4010 434MHz reference keyfob designs.
- WES0021-03.zip: this is what you most likely have in hands. This design uses a separate area for the circuit components.
- WES0021-04.zip: this reference design uses the antenna trace along the entire PCB circumference in order to maximize the antenna gain. (The bigger antenna loop area you have the larger antenna gain you can get.) The circuit components are placed within the antenna loop area.
These are the latest design files for these two different approaches and recommended to follow.
L1 (RF choke) inductor is only needed if larger 2nd harmonic suppression is needed, and then the C5 capacitor (with part of the antenna) can shunt that harmonic to GND. The new designs are ETSI and FCC compliant without the need of L1 and C5.
Depending on the antenna loop size C1 capacitor (between the TX pins) might be required. If it is shown as non-pop, then it means that it is not necessary to mount (non-populated), since the on-chip Si4010 TX capacitance is enough.
HI, thanks for this files. Question, which software are based this files to be able to open? I have tried import wizard from altium without success and couldn´t open.