SA2532 Datasheet, PDF (2/22 Pages) Sames – VERSATILE SINGLE CHIP TELEPHONE

SA2532
PIN DESCRIPTION
Pin# Symbol Function
23 M1
Microphone Inputs
24 M2
Differential inputs for the microphone (electret).
3
RO1
Receiver Outputs
2
RO2
These are the outputs for driving a dynamic earpiece with an impedance
of 100 to 300Ω
5
A
Analog Ground
GND
This is the analog ground for the amplifiers.
28 RI
Receive Input
This is the input for the receive signal.
6
STB
Side Tone Balance Input
This is the input for side tone cancellation.
1
LS
Line Current Sense Input
This is the input for sensing the line current.
27 LI
Line Input
This input is used for power extraction and line current sensing.
25 CS
Current Shunt Control Output
This N-channel open drain output controls the external high power shunt
transistor for the modulation of the line voltage and for shorting the line
during make period of pulse dialling.
4
V_DD
Positive Voltage Supply
This is the supply pin for the circuit.
26 V
SS
8
MO
Negative Power Supply
Melody Output
Pulse Density Modulated output of the melody generator for tone ringer. At
high impedance when not active.
21 FCI
Frequency Comparator Input
This is a Schmitt trigger input for ring frequency discrimination. Disabled
during off-hook.
10 HS/DP Hook Switch Input and Dial Pulse Output
This is an I/O that is pulled high by the hook switch when off- hook. An open
drain pulls it low during break periods of pulse dialling and flash.
11 OSC
Oscillator Input
Oscillator pin for Xtal or ceramic resonator (3.58 MHz).
9
LLC
Line Loss Compensation
Select pin for line loss compensation.
12 RR
Repetition Rate
Select pin for repetition rate of melody.
22 MODE Signalling Mode Select Input
Mode pin Function
High
LD default mode, make/break = 33/66 ms
Open
MF only
Low
LD default mode, make/break = 40/60 ms
20 R1
Keyboard Rows
19 R2
18 R3
17 R4
16 C1
Keyboard Columns
15 C2
14 C3
13 C4
7
CI
Complex Impedance Input
Input pin for the capacitor in the complex impedance
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