SI3050-E-FM Silicon Laboratories Inc, SI3050-E-FM Datasheet - Page 35

• Manufacturer Part Number: SI3050-E-FM
• Description: IC VOICE DAA GCI/PCM/SPI 24-QFN
• Manufacturer: Silicon Laboratories Inc
• Series: -r

Specifications of SI3050-E-FM

• Function: Data Access Arrangement (DAA)
• Interface: GCI, PCM, SPI
• Number Of Circuits: 1
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 8.5mA
• Power (watts): *
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 24-WFQFN Exposed Pad
• Includes: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

with the on-hook transition during pulse dialing. These
tests provide an inductive dc feed resulting in a large
voltage spike. This spike is caused by the line
inductance and the sudden decrease in current through
the loop when going on-hook. The traditional way of
dealing with this problem is to put a parallel RC shunt
across the hookswitch relay. The capacitor is large
(~1 µF, 250 V) and relatively expensive. In the Si3050,
loop current can be controlled to achieve three distinct
on-hook speeds to pass spark quenching tests without
additional BOM components. Through the settings of
four bits in three registers, OHS (Register 16), OHS2
(Register 31), SQ0, and SQ1 (Register 59), a slow ramp
down of loop current can be achieved which induces a
delay between the time the OH bit is cleared and the
time the DAA actually goes on-hook.
To ensure proper operation of the DAA during pulse
dialing, disable the automatic resistor calibration that is
performed each time the DAA enters the off-hook state
by setting the RCALD bit (Register 25, bit 5).
5.22. Receive Overload Detection
The Voice DAA chipset is capable of monitoring and
reporting receive overload conditions on the line. Billing
tones, parallel phone off-hook events, polarity reversals
and other disturbances on the line may trigger multiple
levels of overload detection as described below.
Transient events less than 1.1 V
filtered out by the low-pass digital filter on the Si3050 +
Si3011 and Si3050+Si3019. The ROV and ROVI bits
are set when the received signal is greater than 1.1
V
condition until a zero is written to clear. The OVL mirrors
the function of the ROV and ROVI bits but it
automatically clears after the overload condition has
been removed. When the OVL bit returns to 0, the DAA
initiates an auto-calibration sequence that must
complete before data can be transmitted. An external
interrupt can optionally be triggered by the ROVI bit by
setting the ROVM and INTE bits.
Certain events such as billing tones can be sufficiently
large to disrupt the line-derived power supply of the
Voice DAA line side device (Si3011, Si3018 or Si3019.)
To ensure that the device maintains the off-hook line
state during these events, the BTE bit should be set. If
such an event occurs while the BTE bit is set, the BTD
and BTDI bits will be asserted. A zero must be written to
the BTE bit to clear the BTD and BTDI bits. An external
interrupt can optionally be triggered by the BTDI bit by
setting the BTDM and INTE bits.
In the event that a line disturbance causes the loop
current to collapse below the minimum required
operating current of the Voice DAA, the DOD and DODI
PK
.
Both bits will continue to indicate an overload
PK
on the line are
Rev. 1.4
bits will be set. An external interrupt can optionally be
triggered by the DODI bit by setting the DODM and
INTE bits.
5.23. Billing Tone Filter (Optional)
Optionally, a billing tone filter may be inserted between
the line and the voice DAA to minimize disruptions
caused by large billing tones. The notch filter design
requires two notches, one at 12 kHz and one at 16 kHz.
Because these components are expensive and few
countries utilize billing tones, this filter is typically placed
in an external dongle or added as a population option.
Figure 25 shows a billing tone filter example. Table 19
gives the component values.
L1 must carry the entire loop current. The series
resistance of the inductors is important to achieve a
narrow and deep notch. This design has more than
25 dB of attenuation at both 12 kHz and 16 kHz.
The billing tone filter affects the DAA’s ac termination
and return loss. The global compromise complex ac
termination as selected by ACIM[3:0] = 1111 passes
global return loss specifications with and without the
billing tone filter by at least 3 dB. This ac termination is
optimized
Table 19. Component Values—Optional Billing
Component
From Line
Si3050 + Si3011/18/19
C1,C2
RING
C3
L1
L2
TIP
Figure 25. Billing Tone Filter
for
frequency
3.3 mH, >120 mA, <10  , ±10%
10 mH, >40 mA, <10  , ±10%
Tone Filters
0.027 µF, 50 V, ±10%
0.01 µF, 250 V, ±10%
C1
C2
L1
response
Value
C3
L2
DAA
To
and
hybrid
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