AN2274 Freescale Semiconductor / Motorola, AN2274 Datasheet - Page 18

• Manufacturer Part Number: AN2274
• Description: Generic Tone Generation on the StarCore SC140 Core
• Manufacturer: Freescale Semiconductor / Motorola

Using and Testing the Generic Tone Generator
3.4 Examples of Generated Signaling Tones
Figure 7 and Figure 8 illustrate the spectrum of two typical signaling tones. The figures on the left correspond to
the FFT magnitude plots of actual data generated from the proposed module; the figures on the right correspond to
measured spectra (using a spectrum analyzer). Observe that the noise floor of the measurements is around 80 dB
below the peak values.
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Generic Tone Generation on the StarCore™ SC140/SC1400 Cores, Rev. 1
MATLAB
MATLAB
Figure 8. Germany Dial Tone: 425 or 450 Hz
Figure 7. USA Busy Tone: 480 + 620 Hz
Measured Spectrum
Measured Spectrum
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