SI3210-FT Silicon Laboratories Inc, SI3210-FT Datasheet - Page 45

• Manufacturer Part Number: SI3210-FT
• Description: IC SLIC/CODEC PROGRAMMBL 38TSSOP
• Manufacturer: Silicon Laboratories Inc
• Series: ProSLIC®r
• Type: ProSLIC Programmable CMOS SLICr

Specifications of SI3210-FT

• Package / Case: 38-TSSOP
• Function: Subscriber Line Interface Concept (SLIC), CODEC
• Interface: PCM, SPI
• Number Of Circuits: 1
• Voltage - Supply: 3.3V, 5V
• Current - Supply: 88mA
• Power (watts): 700mW
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Includes: BORSCHT Functions, DTMF Generation and Decoding, FSK Generation, Pulse Metering Generation, Voice Loopback Test Modes
• Product: Telecom
• Supply Current: 4 mA
• Maximum Operating Temperature: 100 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 336-1168

where:
N
I
(max value = 2 mA), and
V
It is good practice to provide a buffer of a few more
milliamperes for I
leakages, etc. The total I
smaller than 80 mA.
where
transistors Q5 and Q6.
The minimum value for V
following:
The ProSLIC is designed to create a fully-balanced
ringing waveform, meaning that the TIP and RING
common mode voltage, (V
voltage
automatically set to the following:
VCMR is an indirect register, which provides the
headroom by the ringing waveform with respect to the
V
Register 40 with an LSB voltage of 1.5 V/LSB.
Register 40 should be set with the calculated V
provide voltage headroom during ringing.
Silicon revisions C and higher support the option to
briefly increase the maximum differential current limit
between the voltage transition of TIP and RING from
OS
AC,PK
REN
BATH
is the offset current flowing in the line driver circuit
LCS
is the ringing REN load (max value = 5),
V
rail. The value is set as a 4-bit setting in indirect
= amplitude of the ac ringing waveform.

OVR
is
VBATH
is the minimum expected current gain of
VCM_RING
Processor
=
referred
Signal
Input
I
LOAD , PK
LFS
LOAD,PK
=
V
AC , PK
=
ISP_OUT

to

------------ -
BATH
VBATH VCMR
--------------------------------------------- -
TIP
to account for possible line
+

+
LOAD,PK
as
1
V

+ V
ROFF
is therefore given by the

2
80.6 
VCM_RING
–
RING
Digital
NRTP
+
LPF
current should be
V
)/2, is fixed. This
OVR
+
Figure 23. Ring Trip Detector
1 V

Threshold
Ring Trip
RPTP
and
OVR
Rev. 1.45
–
+
to
is
ringing to a dc linefeed state. This mode is enabled by
setting ILIMEN = 1 (direct Register 108, bit 7).
2.4.6. Ring Trip Detection
A ring trip event signals that the terminal equipment has
gone off-hook during the ringing state. The ProSLIC
performs ring trip detection digitally using its on-chip A/
D converter. The functional blocks required to
implement ring trip detection are shown in Figure 23.
The primary input to the system is the loop current
sense (LCS) value provided by the current monitoring
circuitry and reported in direct Register 79. LCS data is
processed by the input signal processor when the
ProSLIC is in the ringing state as indicated by the
Linefeed Shadow register (direct Register 64). The data
then feeds into a programmable digital low-pass filter
that removes unwanted ac signal components before
threshold detection.
The output of the low-pass filter is compared to a
programmable threshold, RPTP (indirect Register 29).
The threshold comparator output feeds a programmable
debouncing filter. The output of the debouncing filter
remains in its present state unless the input remains in
the opposite state for the entire period of time
programmed by the ring trip debounce interval,
RTDI[6:0] (direct Register 70). If the debounce interval
has been satisfied, the RTP bit of direct Register 68 will
be set to indicate that a valid ring trip has occurred. A
ring trip interrupt is generated if enabled by the RTIE bit
(direct Register 22). Table 31 lists the registers that
must be written or monitored to correctly detect a ring
trip condition.
The recommended values for RPTP, NRTP, and RTDI
vary according to the programmed ringing frequency.
Register values for various ringing frequencies are
given in Table 32.
DBIRAW
Debounce
Filter
RTDI
Si3210/Si3211
RTP
Interrupt
Logic
RTIE
RTIP
45