參數(shù)資料
型號: MT88L89
廠商: Mitel Networks Corporation
英文描述: 3V Integrated DTMFTransceiver with Adaptive Micro Interface
中文描述: 3V的綜合DTMFTransceiver自適應微型接口
文件頁數(shù): 5/20頁
文件大?。?/td> 352K
代理商: MT88L89
Advance Information
MT88L89
4-129
signal duration to be recognized by the receiver. A
value for C1 of 0.1 μF is recommended for most
Figure 6 - Guard Time Adjustment
V
DD
St/GT
ESt
V
DD
St/GT
ESt
C1
R1
R2
C1
R1
R2
t
GTA
= (R1C1) In (V
DD
/V
TSt
)
R
P
= (R1R2) / (R1 + R2)
t
GTP
= (R
P
C1) In [V
DD
/ (V
DD
-V
TSt
)]
t
GTA
= (R
p
C1) In (V
DD
/V
TSt
)
R
P
= (R1R2) / (R1 + R2)
t
GTP
= (R1C1) In [V
DD
/ (V
DD
-V
TSt
)]
a) decreasing tGTP; (tGTP < tGTA)
b) decreasing tGTA; (tGTP > tGTA)
applications, leaving R1 to be selected by the
designer. Different steering arrangements may be
used to select independent tone present (t
GTP
) and
tone absent (t
GTA
) guard times. This may be
necessary to meet system specifications which place
both accept and reject limits on tone duration and
interdigital pause. Guard time adjustment also allows
the designer to tailor system parameters such as talk
off and noise immunity.
Increasing t
REC
improves talk-off performance since
it reduces the probability that tones simulated by
speech will maintain a valid signal condition long
enough to be registered. Alternatively, a relatively
short t
REC
with a long t
DO
would be appropriate for
extremely noisy environments where fast acquisition
time and immunity to tone drop-outs are required.
Design information for guard time adjustment is
shown in Figure 6. The receiver timing is shown in
Figure 7 with a description of the events in Figure 9.
Call Progress Filter
A call progress mode, using the MT88L89, can be
selected allowing the detection of various tones,
which identify the progress of a telephone call on the
network. The call progress tone input and DTMF
input are common, however, call progress tones can
only be detected when CP mode has been selected.
Figure 7 - Receiver Timing Diagram
V
in
ESt
St/GT
RX
0
-RX
3
b3
b2
Read
Status
Register
IRQ/CP
EVENTS
A
B
C
D
E
F
t
REC
t
REC
t
ID
t
DO
TONE #n
TONE
#n + 1
TONE
#n + 1
t
DP
t
DA
t
GTP
t
GTA
t
PStRX
t
PStb3
DECODED TONE # (n-1)
# n
# (n + 1)
V
TSt
相關PDF資料
PDF描述
MT88L89AC 3V Integrated DTMFTransceiver with Adaptive Micro Interface
MT88L89AE 3V Integrated DTMFTransceiver with Adaptive Micro Interface
MT88L89AN 3V Integrated DTMFTransceiver with Adaptive Micro Interface
MT88L89AP 3V Integrated DTMFTransceiver with Adaptive Micro Interface
MT88L89AS 3V Integrated DTMFTransceiver with Adaptive Micro Interface
相關代理商/技術參數(shù)
參數(shù)描述
MT88L89AC 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:3V Integrated DTMFTransceiver with Adaptive Micro Interface
MT88L89AE 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:3V Integrated DTMFTransceiver with Adaptive Micro Interface
MT88L89AN 制造商:Microsemi Corporation 功能描述:
MT88L89AN1 制造商:Microsemi Corporation 功能描述:DTMF TXRX 3.58MHZ CMOS 3V 24SSOP - Rail/Tube
MT88L89ANR1 制造商:Microsemi Corporation 功能描述:DTMF TXRX 3.58MHZ CMOS 3V 24SSOP - Tape and Reel 制造商:MICROSEMI CONSUMER MEDICAL PRODUCT GROUP 功能描述:IC TXRX DTMF 3V 24SSOP 制造商:Microsemi Corporation 功能描述:IC TXRX DTMF 3V 24SSOP