SI3220-BQ Silicon Laboratories Inc, SI3220-BQ Datasheet - Page 40

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

Specifications of SI3220-BQ

• 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: -40°C ~ 85°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: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Number Of Channels: 2
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Si3220/Si3225
When generating a high-voltage ringing amplitude using
the Si3220, the power dissipated during the OHT state
typically increases due to operating from the ringing
battery supply in this mode. To reduce power, the
Si3220/Si3200
accommodate up to three separate battery supplies by
implementing a secondary battery switch using a few
low-cost external components as illustrated in Figure
22. The Si3220’s BATSEL pin is used to switch between
the VBATH (typically –48 V) and VBATL (typically
–24 V) rails using the switch internal to the Si3200. The
Si3220’s GPO pin is used along with the external
transistor circuit to switch the VRING rail (the ringing
voltage battery rail) onto the Si3200’s VBAT pin when
ringing is enabled. The GPO signal is driven
automatically by the ringing cadence provided that the
RRAIL bit of the RLYCON register is set to 1 (signifying
that a third battery rail is present).
40
Component
VBATH
VBATL
VBAT
Figure 23. 3-Battery Switching with Si3220/
Table 24. 3-Battery Switching Components
R101
D1
Q1
Q2
0.1 µF
0.1 µF
VBAT
VBATH
VBATL
806 kΩ
Si3200
chipset
200 V, 200 mA
1/10 W, ± 5%
100 V PNP
100 V NPN
BATSEL
Value
Si3200
provides
SVBAT
40.2 kΩ
R9
Si3220
IN4003
D1
1N4003 or similar
the
40.2 kΩ
CXT5401 or
CXT5551 or
Comments
R6
V
2.4 k Ω for
3.9 k Ω for
V
DD
similar
similar
DD
R102
Q2
CXT5551
Q1
=3.3 V
ability
=5 V
Preliminary Rev. 0.91
10 kΩ
R101
CXT5401
R103
402 kΩ
to
Ringing Generation
The Si3220-based Dual ProSLIC chipset provides a
balanced ringing waveform, with or without dc offset.
The ringing frequency, cadence, waveshape, and dc
offset are register programmable.
Using a balanced ringing scheme, the ringing signal is
applied to both the TIP and the RING lines using ringing
waveforms that are 180° out of phase with each other.
The resulting ringing signal seen across TIP-RING is
twice the amplitude of the ringing waveform on either
the TIP or the RING line, which allows the ringing
circuitry to withstand half the total ringing amplitude
seen across TIP-RING.
An internal ringing scheme provides >40 Vrms into a
5REN load at the terminal equipment using a user-
provided ringing battery supply. The specific ringing
supply voltage required depends on the ringing voltage
desired.
equipment depends on the loop impedance as well and
Component
V
Table 24. 3-Battery Switching Components
GND
BATH
R102
R103
SLIC
V
V
RING
TIP
The
Figure 24. Balanced Ringing
402 k Ω ,1/10 W,± 1%
10 k Ω ,1/10 W, ± 5%
ringing
V
PK
Value
V
V
RING
TIP
amplitude
V
CM
V
OFF
V
at
OV
RING
Comments
TIP
the
terminal
V
OFF