MT8889CN Zarlink Semiconductor, Inc., MT8889CN Datasheet - Page 6
MT8889CN
Manufacturer Part Number
MT8889CN
Description
Integrated DTMF Transceiver with Adaptive Micro Interface
Manufacturer
Zarlink Semiconductor, Inc.
Datasheet
1.MT8889CN.pdf
(29 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
MT8889CN
Manufacturer:
ZARLINK
Quantity:
20 000
Guard Time Adjustment
The simple steering circuit shown in Figure 5 is adequate for most applications. Component values are chosen
according to the following inequalities (see Figure 7):
V
St/GT
ESt
V
St/GT
ESt
DD
DD
V
DD
MT8889C
St/GT
V
ESt
Figure 6 - Guard Time Adjustment
t
DD
t
R1
Figure 5 - Basic Steering Circuit
REC
R1
REC
t
t
ID
DO
Zarlink Semiconductor Inc.
t
DAmax
t
t
t
DPmax
DAmin
DPmin
MT8889C
t
t
GTA
GTP
t
R1
t
GTP
GTP
R2
a) decreasing tGTP; (tGTP < tGTA)
b) decreasing tGTA; (tGTP > tGTA)
C1
R2
C1
+ t
= (R1C1) In (V
= (R1C1) In [V
+ t
+ t
+ t
= (R
= (R1C1) In [V
6
GTAmax
GTAmin
t
GTPmin
t
GTPmax
GTA
GTA
P
C1) In [V
R
R
Vc
= (R1C1) In (V
P
P
= (R
C1
= (R1R2) / (R1 + R2)
= (R1R2) / (R1 + R2)
- t
- t
- t
p
- t
C1) In (V
DD
DD
DPmin
DPmax
DAmax
DD
DD
DAmin
/ (V
/ V
/ (V
/ (V
TSt
DD
DD
DD
DD
DD
)
-V
-V
-V
/V
/V
TSt
TSt
TSt
TSt
TSt
)]
)]
)]
)
)
Data Sheet