| 摘要 |
An FM transmitter and a small electronic device using the same are provided to reduce the circuit scale of FM transmitters. An FM transmitter(100) comprises a stereo modulator(10), a frequency modulator(20), and the first and second programmable frequency dividers(40,42). The stereo modulator converts inputted audio signals(S1L,S1R) into a stereo composite signal(S2). The frequency modulator comprises a PLL(Phase Locked Loop) circuit, and executes frequency modulation using the stereo composite signal, outputted from the stereo modulator, as a modulation signal. The first programmable frequency divider(40) executes frequency division for an inputted external clock signal(CKext) at the first divider rate and outputs it. The second programmable frequency divider(42) executes frequency division for the external clock signal at the second divider rate and output it. The output signal of the first programmable frequency divider is used as a reference clock signal to create the stereo composite signal. The output signal of the second programmable frequency divider is used as a reference clock signal for the PLL circuit.
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