SI3200-BS Silicon Laboratories Inc, SI3200-BS Datasheet - Page 44

• Manufacturer Part Number: SI3200-BS
• Description: IC LINEFEED INTRFC 100V 16SOIC
• Manufacturer: Silicon Laboratories Inc
• Series: ProSLIC®r

Specifications of SI3200-BS

• Function: Subscriber Line Interface Concept (SLIC), CODEC
• Interface: GCI, PCM, SPI
• Number Of Circuits: 2
• Voltage - Supply: 3.3V, 5V
• Current - Supply: 110µA
• Power (watts): 941mW
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Includes: Battery Switching, BORSCHT Functions, DTMF Generation and Decoding, FSK Tone Generation, Modem and Fax Tone Detection
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Si3232
4.12. Relay Driver Considerations
The Si3232 includes a general-purpose driver output for
each channel (GPOa, GPOb) to drive external test
relays. In most applications, the relay can be driven
directly from the Si3232 with no external relay drive
circuitry required. Figure 21 illustrates the internal relay
driver circuitry using a 3 V relay.
The internal driver logic and drive circuitry is powered
from the same 3.3 V supply as the chip’s main supply
(VDD1–VDD4 pins). When operating external relays
from a V
an internal diode network provides protection against
overvoltage conditions caused by flyback spikes when
the relay is opened. Only 3 V relays may be used in the
configuration shown in Figure 21, and either polarized
or non-polarized relays are acceptable provided both
V
impedance, R
11 Ω while sinking less than the maximum rated 85 mA
into the pin.
If the desired operating voltage of the relay, V
higher than the Si3232’s V
external drive circuit is required to eliminate leakage
from V
In this configuration, a polarized relay is recommended
to provide optimal overvoltage protection with minimal
external components. Figure 22 illustrates the required
external
recommended values for R
characteristics
impedance, R
63 Ω while sourcing less than the maximum rated
28 mA out of the pin.
44
CC
Figure 21. Si3232 Internal Relay Drive Circuitry
Si3232
and V
Driver
Relay
CC
Logic
CC
to V
DD
drive
supply that is equal to the chip’s V
are powered by a 3.3 V supply. The input
OUT
IN
DD
, of the relay driver pins is a constant
and
, of the relay driver pins is a constant
through the internal protection diode.
circuit,
GND
V
DD
V
CC
and
DD
supplies.
DRV
GPOa/b
supply voltage, an
Table 26
for typical relay
V
CC
The
non-polarized)
3 V/5 V Relay
(polarized or
DD
Preliminary Rev. 0.96
provides
supply,
output
CC
, is
The maximum allowable R
using the following equation:
where
Si3232
ProSLIC
3.3 V
3.3 V
3.3 V
3.3 V
3.3 V
±5%
±5%
±5%
±5%
±5%
V
MaxR
(
------------------------------------------------------------------------------------------------ - R
DD
Table 26. Recommended R
Figure 22. Driving Relays with V
V
β
DD,MIN
Q1,MIN
DRV
Relay
±10%
±10%
±10%
–
3.3 V
±5%
±5%
12 V
24 V
48 V
V
V
5 V
~ 30 for a 2N2222
0.6 V
=
CC
CC,MAX
V
DD
) R
(
1028 Ω
2880 Ω
7680 Ω
–
Relay
R
178 Ω
RELAY
64 Ω
GPOa
GPOb
0.3 V
COIL
DRV
) β
(
value can be calculated
Q1,MIN
Maximum
Polarized
Required
11092 Ω
2718 Ω
6037 Ω
8364 Ω
R
relay
I
R
DRV
DRV
Not
DRV
DRV
)
–
CC
V
SOURCE
Values
CC
Q1
> V
5% Value
mended
Recom-
2.7 kΩ
5.6 kΩ
8.2 kΩ
11 kΩ
DD
—