Silan

Semiconductors

SC9200A/B

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0

2001.02.02

5

FUNCTIONAL DESCRIPTION

The SC9200A/B are DTMF generators for

µC interfaces. They are controlled by a µC in the serial mode.

The SC9200A/B employ a data input, a 5-bit code, and a synchronous clock to transmit a DTMF signal. Every

digital of a phone number to be transmitted is selected by a series of inputs that consist of 5-bit data. Of the 5 bits,

the D0 (LSB) is the first received bit. The SC9200A/B will latch data on the falling edge of the clock (CLK pin).

The relationship between the digital codes and the tone output frequency is shown in Table 1 as for the control

timing diagram, refer to Figure 1.

Table 1: Digits vs. input data vs. tone output frequency (serial mode)

Digit

D4

D3

D2

D1

D0

Tone Output Frequency (Hz)

1

0

0

0

0

1

697+1209

2

0

0

0

1

0

697+1336

3

0

0

0

1

1

697+1477

4

0

0

1

0

0

770+1209

5

0

0

1

0

1

770+1336

6

0

0

1

1

0

770+1477

7

0

0

1

1

1

852+1209

8

0

1

0

0

0

852+1336

9

0

1

0

0

1

852+1477

0

0

1

0

1

0

941+1336

*

0

1

0

1

1

941+1209

#

0

1

1

0

0

941+1477

A

0

1

1

0

1

697+1633

B

0

1

1

1

0

770+1633

C

0

1

1

1

1

852+1633

D

0

0

0

0

0

941+1633

--

100

00

697

--

100

01

770

--

100

10

852

--

100

11

941

--

1

0

1

0

0

1209

--

1

0

1

0

1

1336

--

1

0

1

1

0

1477

--

1

0

1

1

1

1633

DTMF OFF

111

11

--

*Notes: The codes not listed in Table 1 are not used D4 is MSB.