Portable audio device having reduced sensitivity to RF interference and related methods
View Patent ↗A portable audio device having reduced sensitivity to RF interference over a predetermined frequency range from an adjacent mobile wireless communications device may include a portable housing, a battery carried thereby, a recharging power input connected to the battery, a digital signal input, and an audio analog signal output. A digital-to-analog converter (DAC) may be carried by the portable housing and powered by the battery for converting a selected digital audio file from a memory into an analog audio signal. An audio analog amplifier may be connected between the DAC and the audio analog signal output. A first RF filter(s) may be connected to the recharging power input, and a second RF filter(s) may be connected to the audio analog signal output, both for reducing RF interference over the predetermined frequency range from the adjacent mobile wireless communications device.
1. A portable electronic device comprising:
a portable housing;
a battery carried by said portable housing;
a recharging power input coupled to said battery;
a signal input;
an audio signal output;
a memory carried by said portable housing and powered by said battery for storing audio files input thereto via said signal input;
an audio analog amplifier powered by said battery and coupled between said memory and said audio signal output;
at least one first RF filter coupled to said recharging power input; and
at least one second RF filter coupled to said audio signal output.
2. The portable electronic device of claim 1 further comprising at least one third RF filter coupled to said signal input.
3. The portable electronic device of claim 2 wherein said at least one third RF filter comprises a parallel coupled capacitor.
4. The portable electronic device of claim 1 further comprising:
an audio input coupled to said audio analog amplifier; and
at least one fourth RF filter coupled to said audio input.
5. The portable electronic device of claim 4 wherein said at least one fourth RF filter comprises a series coupled inductor and a parallel coupled capacitor.
6. The portable electronic device of claim 1 wherein said at least one first RF filter comprises a parallel coupled capacitor.
7. The portable electronic device of claim 1 wherein said at least one second RF filter comprises a series coupled inductor and parallel coupled capacitor.
8. The portable electronic device of claim 1 wherein said at least one first and second filters each filters frequencies in a frequency range of from about 30 MHz to 6 GHz.
9. The portable electronic device of claim 1 wherein the stored audio files comprise digital stereo audio files.
10. The portable electronic device of claim 1 further comprising at least one display carried by said portable housing; and at least one user input device carried by said portable housing.
11. A portable electronic device comprising:
a portable housing;
a battery carried by said portable housing;
a recharging power input coupled to said battery;
a signal input;
an audio signal output;
a memory carried by said portable housing and powered by said battery for storing digital stereo audio files input thereto via said signal input;
an audio analog amplifier powered by said battery and coupled between said memory and said audio signal output;
at least one first RF filter coupled to said recharging power input;
at least one second RF filter coupled to said audio signal output; and
at least one third RF filter coupled to said signal input.
12. The portable electronic device of claim 11 further comprising:
an audio input coupled to said audio analog amplifier; and
at least one fourth RF filter coupled to said audio input.
13. The portable electronic device of claim 11 wherein said at least one first, second and third filters each filters frequencies in a frequency range of from about 30 MHz to 6 GHz.
14. The portable electronic device of claim 11 further comprising at least one display carried by said portable housing; and at least one user input device carried by said portable housing.
15. A method for reducing sensitivity of a portable electronic device to RF interference, the portable electronic device comprising a portable housing, a battery carried by the portable housing, a recharging power input coupled to the battery, a signal input, an audio signal output, a memory carried by the portable housing and powered by the battery for storing audio files input thereto via the signal input, and an audio analog amplifier coupled between the memory and the audio signal output, the method comprising:
coupling at least one first RF filter to the recharging power input; and
coupling at least one second RF filter to the audio signal output.
16. The method of claim 15 further comprising coupling at least one third RF filter to the signal input.
17. The method of claim 16 wherein the at least one third RF filter comprises a parallel coupled capacitor.
18. The method of claim 15 wherein the portable audio device further comprises an audio input coupled to the audio analog amplifier; and further comprising coupling at least one fourth RF filter to the audio input.
19. The method of claim 18 wherein the at least one fourth RF filter comprises a series coupled inductor and a parallel coupled capacitor.
20. The method of claim 15 wherein the at least one first RF filter comprises a parallel coupled capacitor.
21. The method of claim 15 wherein the at least one second RF filter comprises a series coupled inductor and parallel coupled capacitor.
22. The method of claim 15 wherein the at least one first and second filters each filters frequencies in a range of from about 30 MHz to 6 GHz.
23. The method of claim 15 wherein the stored digital audio files comprise digital stereo audio files.
24. The method of claim 15 wherein the portable electronic device further comprises at least one display carried by the portable housing; and at least one user input device carried by the portable housing.