Communication ICs PLL tone decoder IC BA1604 / BA1604F The BA1604 and BA1604F are tone decoder ICs that enable the frequency to be selected in precise detail, using a PLL system.
These ICs are configured of a PLL circuit, a detection circuit, a voltage comparator circuit and an output logic drive circuit.
When the input signal is within the transmission range of the circuit, PLL is synchronized (locked) to the input signal.
At this point, the output voltage of the decoder drops, and the change