U4091BM TEMIC Semiconductors, U4091BM Datasheet - Page 6

• Manufacturer Part Number: U4091BM
• Description: Programmable Telephone Audio Processor
• Manufacturer: TEMIC Semiconductors

READ:
There is a normal and a fast-read cycle.
In the normal read cycle, the microcontroller sends a 4-bit
address followed by the read indicator, then an 8-bit word
is read out. The U4091BM drives the data line.
The fast read cycle is indicated by a strobe signal. With
the following two clocks the U4091BM reads out the sta-
tus bits RFDO and LIDET which indicate that a ringing
signal or a line signal is present (see figures 4, 5 and 6).
DTMF Dialing
The DTMF generator sends a multi-frequency signal
through the matrix to the line. The signal is the result of
the sum of two frequencies and is internally filtered. The
frequencies are chosen from a low and a high frequency
group.
The circuit conforms to the CEPT recommendation
concerning DTMF option.
Two different levels for the low level group and two
different pre-emphasis (2.5 dB and 3.5 dB) can be chosen
by means of the serial bus (rec. T/CF 46–03).
Melody – Confidence Tone Generation
Melody/confidence tone frequencies are given in the
table below.
The frequencies are provided at the DTMF input of the
switch matrix. A sinus wave, a square wave or a pulsed
wave can be selected by the serial bus. Square signal
means the output is half of frequency cycle high and half
low. Pulsed signal means between the high and low
phases are high impedance phases of 1/6 of the period.
U4091BM
6 (29)
0
1
2
3
4
5
6
7
0
1
2
3
DTMFM[0:2]
DTMFF[0:1]
in DTMF
Mode
000
001
010
011
100
101
110
111
00
01
10
11
DTMF generator OFF
Confidence tone melody
on (sinus)
Ringer melody (pulse)
Ringer melody
(square signal)
DTMF (high level)
DTMF (low level)
Frequency
697
770
852
941
Target Specification
Error / %
–0.007
–0.156
0.032
0.316
DTMFF4 in DTMF mode
10
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
11
0
1
2
3
4
5
6
7
8
9
0
1
2
3
DTMFF
00000
00001
00010
00011
00100
00101
00110
01000
01001
01010
01011
01100
01101
10000
10001
10010
10011
10100
10101
10110
11000
11001
11010
00111
01110
01111
10111
11011
11100
11101
11110
11111
[0:4]
DTMFF[2:3]
0
1
in DTMF
1046.5
1244.5
1318.5
1396.9
1480.0
1568.0
1661.2
1760.0
1864.6
1975.5
2093.0
2217.5
2349.3
2663.3
2983.0
1108.7
1174.7
440.0
466.2
493.9
523.2
554.4
587.3
622.3
659.3
698.5
740.0
784.0
830.0
880.0
932.3
987.8
Mode
Pre-Emphasis Selection
Hz
f
00
01
10
11
Tone-
Name
des
ges
des
ges
des
es
as
es
as
a
b
h
c
d
e
g
a
b
h
c
d
e
g
a
b
h
c
d
f
f
2
3
1
2
2
2
3
3
3
4
1
1
2
2
2
2
3
3
3
3
4
2
2
3
3
2
2
3
3
4
Frequency
Error/%
–0.008
–0.016
–0.003
–0.023
–0.129
–0.216
–0.222
–0.169
–0.014
–0.004
–0.335
–0.355
–0.023
–0.129
–0.214
–0.222
–0.241
–0.302
–0.014
0.014
0.018
0.106
0.126
0.288
0.106
0.126
0.665
0.367
0.387
0.771
–––
–––
1209
1336
1477
1633
Rev. A1, 02-Jun-98
2.5 dB
3.5 dB
697
770
852
941
697
770
852
941
697
770
852
941
697
770
852
941
697
770
852
941
697
770
852
941
697
770
852
941
697
770
852
941
DTMF
Error / %
1209
1209
1209
1209
1336
1336
1336
1336
1477
1477
1477
1477
1633
1633
1633
1633
1209
1209
1209
1209
1336
1336
1336
1336
1477
1477
1477
1477
1633
1633
1633
1633
–0.110
–0.020
–0.182
0.123
Key
A
B
C
D
A
B
C
D
1
4
7
*
2
5
8
0
3
6
9
#
1
4
7
*
2
5
8
0
3
6
9
#