u4090b-p ATMEL Corporation, u4090b-p Datasheet - Page 5

• Manufacturer Part Number: u4090b-p
• Description: U4090b-p Monolithic Integrated Feature Phone Circuit Emi Improved
• Manufacturer: ATMEL Corporation

Table 2-1.
4741C–CORD–11/05
Pin
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
1
2
3
4
5
6
7
8
9
Pin Description
SWOUT
IMPSEL
Symbol
SENSE
VRING
TSACL
INLDR
COSC
ATAFS
INLDT
DTMF
VMPS
RFDO
LIDET
MUTX
MICO
TLDT
MIC2
MIC1
GND
VMP
GSA
SAO
THA
SA I
IND
GT
PD
VB
VL
A resistor from this pin to GND sets the amplification of the microphone and DTMF signals, the input
amplifier can be muted by applying VMP to G
Input for DTMF signals, also used for the answering machine and hands-free 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
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
Line voltage
Reference point for DC- and AC-output signals
A small resistor (fixed) connected from this pin to V
effects the line-length equalization characteristics and the line current at which the loudspeaker amplifier
is switched on
Unregulated supply voltage for peripheral circuits (voice switch), limited to typically 7V
Output of loudspeaker amplifier
Unregulated supply voltage for micorcontroller, limited to 6.3V
Regulated supply voltage of 3.3V for peripheral circuits (especially microprocessors), minimum output
current: 2 mA (ringing) 4 mA (speech mode)
Output for driving external switching transistor
40-kHz oscillator for ringing power converter
Input for ringing signal protected by internal Zener diode
Threshold adjustment for ringing frequency detector
Output of ringing frequency detector
Line detect; output is low when the line current is more than 15 mA
Control input for selection of line impedance
1. 600
2. 900
3. Mute of second transmit stage (TXA); also used for indication of external supply (answering machine);
Time constant of anti-clipping of speaker amplifier
Current input for setting the gain of the speaker amplifier, adjustment characteristic is logarithmical, or
RGSA > 2 M , the speaker amplifier is switched off
Speaker amplifier input (for loudspeaker, tone ringer and hands-free use)
Three-state input of transmit mute:
1. Speech condition; inputs MIC1/MIC2 active
2. DTMF condition; input DTMF active. A part of the input signal is passed to the receiving amplifier as a
3. Input DTMF used for answering machine and hands-free use; receive branch not affected
Attenuation of acoustical feedback suppression, maximum attenuation of AFS circuit is set by a resistor
at this pin, without the resistor, AFS is switched off
Input of transmit level detector
Input of receive level detector
Time constant of transmit level detector
Function
last chosen impedance is stored
confidence signal during dialing
T
L
sets the slope of the DC characteristic and also
U4090B-P
L
is shorted by an
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