IDT82V1671AJ IDT, Integrated Device Technology Inc, IDT82V1671AJ Datasheet - Page 49

• Manufacturer Part Number: IDT82V1671AJ
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of IDT82V1671AJ

• Number Of Channels: 4
• On-hook Transmission: Yes
• Polarity Reversal: Yes
• On-chip Ring Relay Driver: Yes
• Operating Supply Voltage (typ): 3.3V
• Operating Temp Range: -40C to 85C
• Package Type: PLCC
• Operating Temperature Classification: Industrial
• Pin Count: 28
• Mounting: Surface Mount
• Operating Current: 95mA
• Operating Supply Voltage (max): 3.465V
• Operating Supply Voltage (min): 3.135V
• Lead Free Status / RoHS Status: Compliant

calculated as:
necessary:
RSLIC & CODEC CHIPSET
In
When measuring the ringing voltage, the following steps are
• Set the level meter integration time (LM_CN[10:0] bits in
• Clear the Offset Register (word DC Offset in the Coe-RAM).
• Measure the DC content with the rectifier disabled.
• Read the result (LM
• Repeat the measurement above should result in LM
• Perform a new measurement with the rectifier enabled. The result
Figure -
GREG15 and GREG16) to be an integer multiple of the period of
measured ringing signal.
following offset value to the Offset Register:
zero.
is the rectified mean value of the measured signal and can be
calculated as:
V
V
V
OFFSET
V
V
T
T
Ring
IO3
IO4 IO3
ip
ip
I
I
Ring
GND
I
27, if R
–
GND
=
=
------------------------------------------------------ - VCM
K
=
=
=
ADDC
=
R
--------------- -
R
--------------- -
R
--------------- -
1
1
---------------------------------- -
N
1
------------------------------------------------------ -
K
R
R
+
1
= R
+
Samples
ADDC
R
2
+
2
×
Value
R
R
2
LM
LM
R
K
2
2
3
2
×
INT
, R
×
Value
Result
×
) from the result registers and write the
×
(
(
LM
V
V
×
(
K
2
×
V
IO4
IO4
INT
K
IO3
Result
= R
N
INT
–
Samples
–
×
–
VCM
V
4
N
VCM
, the external voltage can be
IO3
Samples
)
)
+
+
)
+
VCM
VCM
Value
to be
49
selecting the VDD voltage to the DC level meter. When measuring the
VDD voltage, an internal gain stage (gain = 1/2) is used to divide the
VDD voltage and provide a limited voltage to the level meter. The VDD is
measured with a reference to VCM.
3.9.6.7
meter may cause a voltage offset error. When selecting the VCM voltage
as the source to the DC level meter, the voltage offset can be measured.
Once the offset value is determined, the offset error can be eliminated
by writing an appropriate compensation value to the Offset Register
(word DC Offset in the Coe-RAM).
3.9.6.8
operational amplifier integrated in the RSLIC. The amplifier will output a
signal to the CODEC through the RTIN pin for ring trip detection. But this
amplifier may introduce an offset and affect the ring trip detection result.
The offset can be measured by selecting the RTIN as the source to the
DC level meter. Refer to
Mode” on page 25
• From this result the peak value and the RMS value can be
The power supply of the CODEC (VDD) can be measured by
The filter, A/D conversion and decimation stages in the DC level
In external ringing mode, the sensed ring current signal is fed to an
calculated.
VDD
V
V
V
Peak
RMS
mean
Voltage Offset Measurement
Ring Trip Operational Amplifier Offset Measurement
=
=
=
=



------------------------------------------------------ - VCM
K
for details.
V
----------- -
------------------------------- -
V
ADDC
LM
--------------------------------------------------------- -
Peak
K
2
mean
ADDC
Result
IDT82V1671/IDT82V1671A, IDT82V1074
“3.4.2.1 Ring Trip Detection In External Ringing
2
×
=
LM
×
K
×
----------------------------------------------------------------------------- -
K
INT
×
π
Result
K
ADDC
LM
K
INT
×
ITDC
Result
N
×
×
Samples
N
×
K
Samples
INT
R
×
Sense
K
×
+
ITDC
N
Samples
×
R



×
Sense
2
×
2
×
×
π
2