Typical Use; Application Notes - Hitachi H8/3637 Hardware Manual

11.4

Typical Use

Figure 11.5 shows an example of the use of the DTMF generator.
H8/3637
Note: Numbers at ends of signal lines are pin numbers of HA16808ANT.
11.5

Application Notes

When using the DTMF generator, note the following point:
Be sure that the DTLR setting (DTL4 to DTL0) matches the system clock frequency at the OSC
pins. Normal DTMF signal output frequencies will not be obtained unless the DTLR setting
matches the OSC frequency.
24 kΩ
TONED
VT
ref
P1
4
360 k Ω
Figure 11.5 Connection to HA16808 ANT
19
2 kΩ
20
+0.47 µF
100 kΩ
11
2SC458
DTMF
HA16808ANT
V
ref1
MUTE
279