U4091BM-N Datasheet, PDF (9/38 Pages) ATMEL Corporation – PROGRAMMABLE TELEPHONE AUDIO PROCESSOR

U4091BM-N
Melody - Confidence
Tone Generation
Melody/confidence tone frequencies are given in Table 3.
The frequencies are provided at the DTMF input of the switch matrix. A sinusoidal wave,
a square wave or a pulsed wave can be selected by the serial bus. A square signal
means the output is half of the frequency cycle high and half low. A pulsed signal means
between the high and low phases are high impedance phases of 1/6 of the period.
Table 3. Status of Melody Generating
Decimal
DTMFM[0:2]
Status
0
000
DTMF generator OFF
1
001
Confidence tone melody on (sinus)
2
010
Ringer melody (pulse)
3
011
Ringer melody (square signal)
4
100
DTMF (mid level)
5
101
DTMF (low level)
6
110
DTMF (high level)
7
111
–
Table 4. DTMF Frequencies
Decimal
DTMFF[0:1]
in DTMF Mode
0
00
1
01
2
10
3
11
Frequency
697
770
852
941
Error (%)
-0.007
-0.156
0.032
0.316
Table 5. DTMF Frequencies
Decimal
DTMFF[2:3]
in DTMF Mode
0
00
1
01
2
10
3
11
Frequency
1209
1336
1477
1633
Error (%)
-0.110
0.123
-0.020
-0.182
Table 6. DTMFF4 in DTMF Mode
Pre-emphasis Selection
0
1
Level
2.5 dB
3.5 dB
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4666B–CORD–08/04