SI3050-E-GTR Silicon Laboratories Inc, SI3050-E-GTR Datasheet - Page 27

• Manufacturer Part Number: SI3050-E-GTR
• Description: IC VOICE DAA GCI/PCM/SPI 20TSSOP
• Manufacturer: Silicon Laboratories Inc

Specifications of SI3050-E-GTR

• Function: Data Access Arrangement (DAA)
• Interface: PCM, Serial, SPI
• Number Of Circuits: 1
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 8.5mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-TSSOP
• Includes: Line Voltage Monitor, Loop Current Monitor, Overload Detection, Parallel Handset Detection, Polarity Reversal Detection, TIP and
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power (watts): -
• Lead Free Status / RoHS Status: Supplier Unconfirmed, Lead free / RoHS Compliant

The output then appears to be twice the frequency of
the ring waveform.
The second method to monitor ring detection uses the
ring detect bits (RDTP, RDTN, and RDT). The RDTP
and RDTN behavior is based on the RNG1-RNG2
voltage. When the signal on RNG1-RNG2 is above the
positive ring threshold, the RDTP bit is set. When the
signal on RNG1-RNG2 is below the negative ring
threshold, the RDTN bit is set. When the signal on
RNG1-RNG2 is between these thresholds, neither bit is
set.
The RDT behavior is also based on the RNG1-RNG2
voltage. When the RFWE bit is 0, a positive ring signal
sets the RDT bit for a period of time. When the RFWE
bit is 1, a positive or negative ring signal sets the RDT
bit.
The RDT bit acts like a one shot. When a new ring
signal is detected, the one shot is reset. If no new ring
signals are detected prior to the one shot counter
reaching 0, then the RDT bit clears. The length of this
count is approximately 5 seconds. The RDT bit is reset
to 0 by an off-hook event. If the RDTM bit
(Register 3, bit 7) is set, a hardware interrupt occurs on
the AOUT/INT pin when RDT is triggered. This interrupt
can
(Register 4, bit 7). When the RDI bit (Register 2, bit 2) is
set, an interrupt occurs on both the beginning and end
of the ring pulse as defined by the RTO bits
(Register 23, bits 6:3). Ring validation may be enabled
when using the RDI bit.
The third method to monitor detection uses the DTX
data samples to transmit ring data. If the ISOcap is
active (PDL=0) and the device is not off-hook or in
on-hook line monitor mode, the ring data is presented
on DTX. The waveform on DTX depends on the state of
the RFWE bit.
When RFWE is 0, DTX is –32768 (0x8000) while the
RNG1-RNG2 voltage is between the thresholds. When
a ring is detected, DTX transitions to +32767 when the
ring signal is positive, then goes back to –32768 when
the ring is near 0 and negative. Thus a near square
wave is presented on DTX that swings from –32768 to
+32767 in cadence with the ring signal.
When RFWE is 1, DTX sits at approximately +1228
while the RNG1-RNG2 voltage is between the
thresholds. When the ring becomes positive, DTX
transitions to +32767. When the ring signal goes near 0,
DTX remains near 1228. As the ring becomes negative,
the DTX transitions to –32768. This repeats in cadence
with the ring signal.
To observe the ring signal on DTX, watch the MSB of
the data. The MSB toggles at the same frequency as
be
cleared
by
writing
to
the
RDTI
Rev. 1.11
bit
the ring signal independent of the ring detector mode.
This method is adequate for determining the ring
frequency.
5.19. Ring Validation
Ring validation prevents false triggering of a ring
detection by validating the ring parameters. Invalid
signals, such as a line-voltage change when a parallel
handset goes off-hook, pulse dialing, or a high-voltage
line test are ignored. Ring validation can be enabled
during normal operation and in low-power sleep mode
when a valid external PCLK signal is supplied.
The ring validation circuit operates by calculating the
time between alternating crossings of positive and
negative ring thresholds to validate that the ring
frequency is within tolerance. High and low frequency
tolerances are programmable in the RAS[5:0] and
RMX[5:0] fields. The RCC[2:0] bits define how long the
ring signal must be within tolerance.
Once the duration of the ring frequency is validated by
the RCC bits, the circuitry stops checking for frequency
tolerance and begins checking for the end of the ring
signal, which is defined by a lack of additional threshold
crossings for a period of time configured by the
RTO[3:0] bits. When the ring frequency is first validated,
a timer defined by the RDLY[2:0] bits is started. If the
RDLY[2:0] timer expires before the ring timeout, then
the ring is validated and a valid ring is indicated. If the
ring timeout expires before the RDLY[2:0] timer, a valid
ring is not indicated.
Ring validation requires the following five parameters:





The RNGV bit (Register 24, bit 7) enables or disables
the ring validation feature in both normal operating
mode and low-power sleep mode.
Ring validation affects the behavior of the RDT status
bit, the RDTI interrupt, the INT pin, and the RGDT pin.
Timeout parameter to place a lower limit on the
frequency of the ring signal (the RAS[5:0] bits in
Register 24). The frequency is measured by
calculating the time between crossings of positive
and negative ring thresholds.
Minimum count to place an upper limit on the
frequency (the RMX[5:0] bits in Register 22).
Time interval over which the ring signal must be the
correct frequency (the RCC[2:0] bits in Register 23).
Timeout period that defines when the ring pulse has
ended based on the most recent ring threshold
crossing.
Delay period between when the ring signal is
validated and when a valid ring signal is indicated to
accommodate distinctive ringing.
Si3050 + Si3011
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