SI3220-KQ Silicon Laboratories Inc, SI3220-KQ Datasheet - Page 42

• Manufacturer Part Number: SI3220-KQ
• Description: IC SLIC/CODEC DUAL-CH 64TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: ProSLIC®r

Specifications of SI3220-KQ

• Package / Case: *
• Function: Subscriber Line Interface Concept (SLIC), CODEC
• Interface: GCI, PCM, SPI
• Number Of Circuits: 2
• Voltage - Supply: 3.3V, 5V
• Current - Supply: 65mA
• Power (watts): 941mW
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Includes: Battery Switching, BORSCHT Functions, DTMF Generation and Decoding, FSK Tone Generation, Modem and Fax Tone Detection
• Product: Telecom
• Supply Voltage (min): 3.13 V
• Supply Current: 22 mA
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Number Of Channels: 2
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Si3220/Si3225
Internal Sinusoidal Ringing
A sinusoidal ringing waveform is generated by the on-
chip digital tone generator. The tone generator used to
generate ringing tones is a two-pole resonator with a
programmable frequency and amplitude. Since ringing
frequencies are low compared to the audio band
signaling frequencies, the sinusoid is generated at a
1 kHz rate. The ringing generator is programmed via the
RINGFREQ, RINGAMP, and RINGPHAS registers. The
equations are as follows:
For example, to generate a 60 V
ringing signal, the equations are as follows:
In addition to the variable frequency and amplitude, a
selectable dc offset (V
waveform is included. The dc offset is defined in the
RINGOF RAM location.
As with the tone generators, the ringing generator has
two timers which function as described above. They
42
RINGAMP
Ringing Initial Phase
Sinusoidal
Trapezoid
External Ringing
Ringing Relay Driver Enable
(Si3225 only)
Ringing Overhead Voltage
RINGAMP
RINGFREQ
0x7EFD9D
Table 25. Register and RAM Locations Used for Ringing Generation (Continued)
Parameter
=
coeff
1
-- -
4
RINGFREQ
=
-------------------- -
1.99211
coeff
00789
1
-- - 1 coeff
4
=
=
RINGPHAS
99211
cos
----------------------- -
1
OFF
=
+
–
coeff


×
cos
-------------------- -
1000Hz
), which can be added to the
(
2π20
×
2
=
15


(
2
-------------------- -
1000Hz
×
coeff 2
)
23
×
2πf
(
=
2
)


-------------------- -
160.173
15
=
0
=
rms
(
RELAYCON
RINGPHAS
)
Mnemonic
85
99211
VOVRING
8322461
Register/


×
23
DesiredV
---------------------------------
RAM
)
(87 V
160.173V
=
273
PK
=
=
Preliminary Rev. 0.91
), 20 Hz
PK
0x111
RINGPHAS[15:0]
VOVRING[15:0]
Register/RAM
RDOE
Bits
allow on/off cadence settings up to 8 s on/8 s off. In
addition to controlling ringing cadence, these timers
control the transition into and out of the ringing state.
To initiate ringing, the user must program the
RINGFREQ,
addresses as well as the RINGTA and RINGTI registers,
and select the ringing waveshape and dc offset. After
this is done, TAEN and TIEN bits are set as desired.
Ringing state is invoked by a write to the linefeed
register. At the expiration of RINGTA, the Dual ProSLIC
turns off the ringing waveform and goes to the on-hook
transmission state. At the expiration of RINGTI, ringing
is initiated again. This process continues as long as the
two timers are enabled and the linefeed register
remains in the ringing state.
Internal Trapezoidal Ringing
In
waveform, the Dual ProSLIC can generate a trapezoidal
ringing waveform similar to the one illustrated in
Figure 26.
RINGPHAS RAM addresses are used for programming
the ringing wave shape as follows:
RINGPHAS = 4 x Period x 8000
RINGAMP = (Desired V/160.8 V) x (2
RINGFREQ = (2 x RINGAMP)/(t
RINGFREQ is a value that is added or subtracted from
the waveform to ramp the signal up or down in a linear
fashion. This value is a function of rise time, period, and
amplitude, where rise time and period are related
through the following equation for the crest factor of a
trapezoidal waveform.
where
addition
The
Enabled/Disabled
to
Programmable
RINGAMP,
0 to 662.83 mA
0 to 1.024 s
0 to 63.3 V
t
RISE
the
Range
RINGFREQ,
N/A
=
traditional
3
-- - T 1
4


and
–
RISE
---------- -
CF
1
2
RINGPHAS
sinusoidal


2.6 mA (20.3 µ A)
x 8000)
15
RINGAMP,
Resolution
)
(LSB Size)
(4.907 mV)
31.25 µ s
1.005 V
N/A
N/A
ringing
RAM
and