U2090B
| Model | U2090B |
| Description | Monolithic Integrated Feature Phone Circuit |
| PDF file | Total 34 pages (File size: 675K) |
| Chip Manufacturer | ATMEL |
U4090B
GT
DTMF
MICO
MIC2
MIC1
PD
IND
VL
GND
SENSE
VB
SAO
Pin Description
1
2
3
4
5
6
7
8
9
10
11
44
43
42
41
40
39
38
37
36
35
34
TXIN
RECIN
TTXA
2
GR
RECO1
RAC
STIL
STIS
RECO2
MUTR
VM
STO
IREF
AGA
TLDR
TLDT
INLDR
INLDT
ATAFS
MUTX
15
SAI
GSA
12
13
14
11
8
9
10
V
L
GND
7
IND
3
4
5
6
MICO
MIC 2
MIC 1
PD
DTMF
Pin
1
Symbol
Function
A resistor from this pin to GND sets the
G
T
amplification of microphone and DTMF
signals, the input amplifier can be muted
by applying VMP to G
T
.
Input for DTMF signals,
also used for the answering machine
and handsfree input
Output of microphone preamplifier
Non-inverting input of microphone
amplifier
Inverting input of microphone
amplifier
Active high input for reducing the
current consumption of the circuit,
simultaneously V
L
is shorted by an
internal switch
The internal equivalent inductance of
the circuit is proportional to the value
of the capacitor at this pin,
a resistor connected to ground may be
used to reduce the dc line voltage
U4090B
12
33
32
31
30
29
28
27
26
25
24
23
94 7905 e
VMPS 13
VMP 14
SWOUT
COSC
VRING
THA
RFDO
LIDET
IMPSEL
TSACL
15
16
17
18
19
20
21
22
16
Line voltage
Reference point for dc- and ac-output
signals
SENSE A small resistor (fixed) connected
from this pin to V
L
sets the slope of
the dc characteristic and also effects
the line length equalization
characteristics and the line current at
which the loudspeaker amplifier is
switched on
V
B
Unregulated supply voltage for
peripheral circuits (voice switch),
limited to typically 7 V
SAO Output of loudspeaker amplifier
V
MPS
Unregulated supply voltage for
µP,
limited to 6.3 V
V
MP
Regulated supply voltage 3.3 V for
peripheral circuits (especially
microprocessors),
minimum output current: 2 mA
(ringing)
4 mA (speech mode)
SWOUT
Output for driving external switching
transistor
COSC 40 kHz oscillator for ringing power
converter
6 (34)
Preliminary Information
TELEFUNKEN Semiconductors
Rev. C1, 28-Oct-96
