Question: I am looking on page 9 of the [TI CC8520 Documentation](http://www.ti.com/lit/ds/symlink/cc8520.pdf) and I see that there are some capacitors and inductors around the antenna with labels such as C306. What does that mean? How can I know the values of these components?

Answer: 
You may be able to run the microcontroller (μC), motor, solenoid from a single power source1. That's probably the first approach that you should try. Make sure to include back-EMF diodes for motor and solenoid.

1 Of course, you need to generate the appropriate supply voltages from that power source. I assume that you understand this.

Solenoids and motors can in fact generate voltage spikes, which may cause problems for the μC. For example, spikes can cause a brownout. (Such spikes are a type of conducted interference. The term "noise" is often used for such nuisances. More rigorous definition of noise [here](http://en.wikipedia.org/wiki/Noise_%28electronics%29).) Whether you will encounter these problems or not depends on the size of the coils and the capacitance between the supply rail and ground in your circuit.

Here's a [related thread](https://electronics.stackexchange.com/q/67768/7036), where someone ran into problems with spikes generated by a solenoid valve.

**edit:**  

Here's a [detailed answer](https://electronics.stackexchange.com/a/66309/7036) in another related thread.  

Here's a [page on EMI suppression for motors](http://www.beam-wiki.org/wiki/Reducing_Motor_Noise).
When people talk about "power supply" they mean one of two things:

1. power source
2. power regulating circuit

What is meant by having two power supplies is not using two batteries but having two separate independent power regulating circuits.

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Noise refers to voltage that changes rapidly (and usually randomly). The reason motors solenoids make circuits noisy is that they generate back-EMF which creates temporary voltage spikes in the circuits. In the case of motors the spikes are periodic.