AK2363 Datasheet, PDF (25/33 Pages) Asahi Kasei Microsystems – Radio Signaling LSI

ASAHI KASEI
[AK2363]
DTMF Receiver Operation
1) DTMF Receiver
The DTMF Receiver detects a received DTMF signal and outputs a 4-bit code.
The output 4-bit codes are listed below.
Output code table
Low tone
[Hz]
High tone
[Hz]
KEY
SD3
(MSB)
SD2
SD1
1209
1
0
0
0
697
1336
2
0
0
1
1477
3
0
0
1
1209
4
0
1
0
770
1336
5
0
1
0
1477
6
0
1
1
1209
7
0
1
1
852
1336
8
1
0
0
1477
9
1
0
0
1336
0
1
0
1
941
1209
*
1
0
1
1477
#
1
1
0
697
1633
A
1
1
0
770
1633
B
1
1
1
852
1633
C
1
1
1
941
1633
D
0
0
0
SD0
(LSB)
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
2) Decoding result output
The result of DTMF RX signal decoding is output on the SD pin through the internal output buffer.
The internal output buffer is controlled with the LOADN pin.
LOADN pin input
0
1
SD pin output
Decoding result output
High level output
MS0583-E-01
- 25 -
2008/06