
¡ Semiconductor
When the DTMF tone is sent
TEN
tSDT
tHDT
DTG1
DTG2
DTG3
DTG4
DTO
941 Hz + 1447 Hz
Figure 2 DTMF Transmit Timing
When the call progress tone (CPT) is detected
400 Hz
AIN
CP
CPW = "1"
MSM7715
CP
CPW = "0"
tDELCP
tHOLCP
Figure 3 Call Progress Tone Detect Timing
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