SI3216PPQ1-EVB Silicon Laboratories Inc, SI3216PPQ1-EVB Datasheet - Page 28

• Manufacturer Part Number: SI3216PPQ1-EVB
• Description: BOARD EVAL W/SI3201 INTERFACE
• Manufacturer: Silicon Laboratories Inc
• Series: ProSLIC®r

Specifications of SI3216PPQ1-EVB

• Main Purpose: Interface, Analog Front End (AFE)
• Utilized Ic / Part: Si3216
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Secondary Attributes: -
• Embedded: -
• Primary Attributes: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Si3216
2.1.2. Linefeed Architecture
The ProSLIC is a low-voltage CMOS device that uses
either an Si3201 linefeed interface IC or low-cost
external components to control the high voltages
required for subscriber line interfaces. Figure 17 is a
simplified illustration of the linefeed control loop circuit
for TIP or RING and the external components used.
The ProSLIC uses both voltage and current sensing to
control TIP and RING. DC and ac line voltages on TIP
and RING are measured through sense resistors R
and R
transistors Q
isolates the high-voltage base of Q
The ProSLIC measures voltage at various nodes in
order to monitor the linefeed current. R
R
sense circuitry is calibrated on-chip to guarantee
measurement
component tolerances. See 2.1.9."Linefeed Calibration"
on page 33 for details.
2.1.3. Linefeed Operation States
The ProSLIC linefeed has eight states of operation as
shown in Table 22. The state of operation is controlled
using the Linefeed Control register (direct Register 64).
The Open state turns off all currents into the external
bipolar transistors and can be used in the presence of
fault conditions on the line and to generate Open Switch
Intervals (OSIs). TIP and RING are tri-stated with a dc
output impedance of about 150 k  . The ProSLIC can
also automatically enter the Open state if it detects
excessive power being consumed in the external bipolar
transistors. See 2.1.5."Power Monitoring and Line Fault
Detection" on page 30 for more details.
In the Forward Active and Reverse Active states,
linefeed circuitry is on, and the audio signal paths are
disabled.
transmission states, audio signal paths are enabled to
provide data transmission during an on-hook loop
condition.
The TIP Open state turns off all control currents to the
external bipolar devices connected to TIP and provides
an active linefeed on RING for ground start operation.
The RING Open state provides similar operation with
the RING drivers off and TIP active.
The
waveforms onto the line.
2.1.4. Loop Voltage and Current Monitoring
The ProSLIC continuously monitors the TIP and RING
voltages and external BJT currents. These values are
available in registers 78–89. Table 23 on page 30 lists
the values that are measured and their associated
28
BAT
provide access to these measuring points. The
Ringing
AC
, respectively. The ProSLIC uses linefeed
In
P
and Q
the
state
accuracy
forward
N
drives
to drive TIP and RING. Q
with
and
programmable
N
standard
from the ProSLIC.
reverse
DC
, R
external
on-hook
SE
ringing
, and
DC
DN
Rev. 1.0
registers. An internal A/D converter samples the
measured voltages and currents from the analog sense
circuitry and translates them into the digital domain. The
A/D updates the samples at an 800 Hz rate. Two
derived values are also reported—loop voltage and loop
current. The loop voltage, V
1-bit sign, 6-bit magnitude format. For ground start
operation, the reported value is the RING voltage. The
loop current, (I
bit sign, 6-bit magnitude format. In RING open and TIP
Open states, the loop current is reported as (I
(I
Q5
–I
Q6
).
Q1
– I
Q2
+ I
Q5
TIP
–I
– V
Q6
)/2, is reported in a 1-
RING
, is reported as a
Q1
– I
Q2
) +