IL6840
Figure2 : Single output applied pin#6
1 F, 250VAC
0.22 F
10K
2.2 K
R2
TIP
C2
10K
5
4
8
6
TEL
7
IL6840
Piezo
VOUT
C3
10 F
2
1
3
1300:8
RING
R1
14K
C1
100nF
VS
f1 = 3.22 •104 / R1 (KΩ); f2 = 5/7 f1; fsweep = 1000 / C1(nF)
DESCRIPTION
The IL6840 tone ringer derives its power supply by rectifying the AC ringing signal. It uses this power to activate
two tone generators. The two tone frequencies generated are switched by internal oscillator in a fast sequence and made
audible across an output amplifier in the loudspeaker; both tone frequencies and the switching frequency can be
externally adjusted.
The device can drive either directly a piezo ceramic converter (buzzer) or small loudspeaker. In case of using a
loud-speaker, a transformer is needed.
An internal shunt voltage regulator provides DC voltage to the output stage, low frequency oscillator, and high
frequency oscillator. To protect the IC from telephone line transients, a zener Diode is included.
4
INTEGRAL [ INTEGRAL CORP. ]
