BA1604 Datasheet, PDF (1/5 Pages) Rohm – PLL tone decoder IC

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 turns on the transistors for the voltage comparator
and output logic drive circuits. A load of up to 100mA can be driven.The center frequency (f0) of the decoder is set by
the mobile oscillation frequency of the current control oscillator. This frequency is determined by selecting a CR con-
nected to Pins 5 and 6.
FApplications
Telephones
Data communication systems
Remote control systems
FFeatures
1) The detection bandwidth can be varied independent-
ly between 0 and 14%.
2) The output circuit can withstand a load current of up
to 100mA, and is directly coupled to the logic circuit.
3) The center frequency offers a high level of stability.
4) High out-of-band signal and noise rejection capabili-
ty.
5) Frequency can be changed over a range of 20 : 1 us-
ing an external resistor.
6) Compatible with EXAR XR-567 and Signetics
NE567.
FBlock diagram
212