am7945 Advanced Micro Devices, am7945 Datasheet - Page 11

• Manufacturer Part Number: am7945
• Description: Subscriber Line Interface Circuit
• Manufacturer: Advanced Micro Devices

Thermal Management Equations (Normal Active and Tip Open States)
P
Z
Z
R
C
R
I
C
R
P
OHT
RTMG
SLIC
T
RX
DC1
DC
D
CAS
TMG
=
=
=
=
+
=
200 Z
=
=
375
-------- -
I
R
---------- -
G
=
1.5 ms
------------------------------- -
T
500 V 0.66
------------------------------- -
R
Z
V
---------------------------- -
3.4 10
DC2
42L
V
DC1
------------------------------------------------------------- -
L
,
BAT
V
BAT
I
2WIN
LOOP
BAT
=
C
+
1
------------------------------------------------------ -
Z
Note:
E0 High enables DET.
D
–
------------- -
I
R
T
LOOP
500
5
R
------------------------------- -
R
=
6 V
–
–
DC2
I
+
State
DC1
L
DC1
f
6 V
2R
0.5 ms
---------------- -
200 Z
R
c
–
0
1
2
3
4
5
6
7
R
200 Z
TMG
F
+
D
P
–
RTMG
R
R
L
DC2
I
DC2
L
+
C3 C2 C1
T
2 R
0
0
0
0
1
1
1
1
–
R
L
R
L
2
0
0
1
1
0
0
1
1
Table 2. User-Programmable Components
F
I
L
0
1
0
1
0
1
0
1
2
+
0.12 W
Table 1. SLIC Decoding
2-Wire Status
Open Circuit
Ringing
Active
On-Hook TX (OHT)
Tip Open
Standby
Reserved
Reserved
SLIC Products
Z
resistors are R
impedance. When computing Z
pole and any external stray capacitance between VTX and
RSN must be taken into account.
Z
G
R
pin. R
desired loop current in the constant-current region.
R
I
OHT loop current (constant-current region).
C
cutoff frequency.
R
dissipation within the SLIC in Normal Active and Tip Open
states only.
Power dissipated in the T
Tip Open states.
Power dissipated in the SLIC while in Active and Tip Open
states.
T
T
RX
DC1
D
CAS
TMG
42L
is the threshold current between on hook and off hook.
is connected between the VTX and RSN pins. The fuse
and C
is connected from V
, R
is the desired receive gain.
DC1
is the regulator filter capacitor and f
is connected from T
DC2
Ring trip
Ring trip
Loop detector
Loop detector
Loop detector
Loop detector
D
and R
form the network connected from RD to –5 V and
, and C
E1 = 1
F
, and Z
DC2
DC
DET Output
are approximately equal. I
form the network connected to the RDC
2WIN
RX
MG
MG
to R
is the desired 2-wire AC input
resistor, R
to V
Ring trip
Ring trip
Ground key
Ground key
Ground key
Ground key
T
SN
, the internal current amplifier
BAT
E1 = 0
. Z
and is used to limit power
T
TMG
is defined above, and
c
, during Active and
is the desired filter
LOOP
is the
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