Silan
Semiconductors
SC9270C/D
3. Tone duration = 40mS Tone pause = 40mS.
4. Nominal DTMF frequencies are used.
5. Both tones in the composite signal have an equal amplitude.
6. Tone pair is deviated by ±1.5% ±2Hz.
7. Bandwidth limited (3kHz) Gaussian Noise.
8. The precise dial tone frequencies are (350Hz and 440Hz) ±2%.
9. For an error rate of less than 1 in 10,000.
10. Referenced to the lowest level frequency component in DTMF signal.
11. Referenced to the minimum valid accept.
12. For guard time calculation purpose.
13. Referenced to Fig.10 Input DTMF Tone level at –25dBm(-28dBm at GS Pin) interference Frequency
Range between 480—3400Hz.
5V
SC9270C 0.1µf
100nf
100kΩ
100kΩ
1 IN+
2 IN-
3 GS
VDD 18
St/GT 17
ESt 16
4 VREF
StD 15
5 IC
Q4 14
6 IC
3.58MHz 7 OSCI
Q3 13
Q2 12
8 OSCO Q1 11
9 VSS
TOE 10
100nf
300kΩ
Figure 2. Single ended input cofiguration
5V
Vin
5V
100nf
100kΩ
100kΩ
3.58MHz
SC9270D 0.1µf
1 IN+
VDD 18
2 IN-
St/GT 17
3 GS
ESt 16
4 VREF
StD 15
5 INH
Q4 14
6 PWDN Q3 13
7 OSCI
Q2 12
8 OSCO Q1 11
9 VSS
TOE 10
100nf
300kΩ
Figure 3. Single ended input cofiguration
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.1 2001.04.27
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