AN1500A
6 General Description
The SA2532K device was developed to provide “plug & play” solution for the Indian DOT, emphasizing high
performance voice transmission and reception. In spite of the fact that voice transmission and reception are the
most vital features in telephony, they are very often ignored or given lower priority compared with some more or
less useless non-voice features. No compromises were accepted during the design phase of the SA2532K, which
is based on the SA2531/2 speech circuit and which supersedes even the hardest PTT requirements worldwide.
The dialler part is based on a long history of producing a wide range of dialer circuits with user-friendly features in
compliance with various national PTT regulations. This knowledge enabled us to develop a specific product to meet
with DOT type approval.
The last piece in the puzzle to complete the full picture of the first CMOS single chip POT was the tone ringer. A
ring frequency discrimination circuit was implemented to avoid false “bell-tinkle” during pulse dialing from a parallel
telephone. The 3-tone melody generator provides the ringing signal.
Note: all the subsequent component numbering is referenced to the AN1500 schematic, shown in pt.22
7 Demo board configuration
The SA2532K is the rare combination of advanced technology and down-to-earth simplicity providing easy and
uncomplicated design effort for the telephone manufacturer. No fussing around: Simply go by the straight forward
guidelines supplied by a highly experienced application group. No technology stress but appealing functionality.
See Fig. 1 for configuration locations:
Sidetone Network
J1 :Line terminal selection
J2: Dial Mode
Selection
Handset Connector
Line connector
J3: line loss compensation
selector
Ringer Capsule
Connector
Fig. 1: Demo board configuration
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sames
SAMES [ SAMES ]
