75T2089/2090/2091
DTMF Transceivers
CALL PROGRESS DETECTOR: Electrical Characteristics
(Continued)
PARAMETER
TON
TON
TOFF
TOFF
TD2
TR2
Signal Time for Detect
Signal Time for No Detect
Interval Time for Detect
Interval Time for No Detect
CONDITIONS
MIN
40
NOM
MAX
10
UNIT
ms
ms
ms
ms
ms
ms
40
20
40
40
Detect Time
Release Time
TON
TOFF
TON
TOFF
tone burst 1
DIN
TD1
TR1
tone burst 2
tone burst 1
DIN
TD1
TR1
tone burst 2
DV
TSU1
THD1
DV
TSU1
THD1
D0, D1, D2, D3
TED
TER
D0, D1, D2, D3
ED
*
*
75T2091 only
FIGURE 6: DTMF Decoder
FIGURE 7: Call Progress Detector
(75T2090/2091 only)
THD2
D4, D5, D6, D7
TSU2
TPW
LATCH
TPW
(SEE NOTE)
RESET
TSTART
TRP
DTMF OUT
NOTE: THE INDICATED TIME MAY BE AS SMALL AS 0 SEC., MEANING THAT THE
LATCH AND RESET LINES MAY BE TIED TOGETHER.
FIGURE 8: DTMF Generator
7
TDK [ TDK ELECTRONICS ]
