stlc3075 STMicroelectronics, stlc3075 Datasheet - Page 14

• Manufacturer Part Number: stlc3075
• Description: Integrated Pots Interface For Home Access Gateway And Wll
• Manufacturer: STMicroelectronics

Functional description
3.2.6
Table 6.
14/36
RRX
RREF
CSVR
RD
CAC
RP
RLIM
RTH
CREV
RDD
CVCC
Name
Rx input bias resistor
Bias setting current
Negative battery filter
Ring trip threshold setting
resistor
AC/DC split capacitance
Line protection resistor
Current limiting programming
Off-hook threshold
programming (Active mode)
Reverse polarity transition
time programming
Pull up resistors
Internally supply filter
capacitor
External components list
In order to properly define the external components value the following system parameters
have to be defined:
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External components for buckboost configuration
the AC input impedance shown by the SLIC at the line terminals Zs to which the return
loss measurement is referred. It can be real (typ. 600 ) or complex.
the AC balance impedance, it is the equivalent impedance of the line ‘Zl’ used for
evaluation of the trans-hybrid loss performances (2/4 wire conversion). It is usually a
complex impedance.
the value of the two protection resistors Rp in series with the line termination.
the line impedance at the TTX frequency Zlttx
the metering pulse level amplitude measured at line termination V
order filtering, V
component (typ. 12 or 16kHz)
the pulse metering envelope rise and decay time constant
the slope of the ringing waveform V
the value of the constant current limit current ’Ilim’
the value of the off-hook current threshold I
the value of the ring trip rectified average threshold current I
the value of the required self generated negative battery V
is 70V). This value can be obtained from the desired ring peak level + 5V.
the value of the maximum current peak drawn from V
Function
LOTTX
represents the amplitude (Vrms) of the fundamental frequency
RREF = 1.3/Ibias
Ibias = 50 A
CSVR = 1/(2
fp = 50Hz
RD = 100/I
2K < RD < 5K
Rp > 30
RLIM = 1300/Ilim
32.5k < RLIM < 65k
RTH = 290/I
27k < RTH < 52k
CREV = ((1/3750) · T/ V
RTH
TH
Formula
TR
fp
/
T
1.8M )
TH
TR
)
POS
22 F 20% 15V @ RD = 4.12k
BATR
’IPK’.
4.12k 1%@ IRTH = 24mA
52.3k 1% @ Ilim = 25mA
22nF 10% 10V @ 12V/ms
32.4k 1% @ I
RTH
in ring mode (max value
100nF 20% 10V
LOTTX
1.5nF 10%
Typ. value
100k 5%
26k 1%
50 1%
100k
100V
. In case of low
TH
= 9mA
STLC3075