U4089B-PFN ATMEL [ATMEL Corporation], U4089B-PFN Datasheet - Page 3

• Manufacturer Part Number: U4089B-PFN
• Description: Monolithic Integrated Feature Phone Circuit
• Manufacturer: ATMEL [ATMEL Corporation]

Pin Configuration
Figure 3. Pinning SSO44
Pin Description
4518A–CORD–05/02
Note:
Pin
10
13
20
21
22
23
11
1
3
4
6
7
8
9
Filters against electromagnetic interference (EMI) are located at the Pins MIC1, MIC2, RECIN and STI.
IMPSEL
Symbol
SENSE
TSACL
DTMF
MIC 2
MIC 1
GND
SAO
GSA
SA I
IND
V
V
V
MP
B
L
Function
Input for DTMF signals. Also used for the answering machine and hands-free input.
Non-inverting input of microphone amplifier.
Inverting input of microphone amplifier.
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
affects the line-length equalization characteristics as well as the line current at which the loudspeaker
amplifier is switched on.
Unregulated supply voltage for peripheral circuits (voice switch); limited to typically 7 V.
Output of loudspeaker amplifier.
Regulated supply voltage 3.3 V for peripheral circuits. The maximum output current is 2 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);
last chosen impedance is stored.
Time constant of anti-clipping of speaker amplifier.
Current input for setting the gain of the speaker amplifier. Adjustment characteristic is logarithmical.
For RGSA > 2 M
Speaker amplifier input (for loudspeaker, tone ringer and hands-free use).
the speaker amplifier is switched off.
L
sets the slope of the DC characteristic and also
U4089B-P
3