SI3068-B-FT Silicon Laboratories Inc, SI3068-B-FT Datasheet - Page 11

• Manufacturer Part Number: SI3068-B-FT
• Description: IC DAA FCC+ EMBEDDED 10SOIC
• Manufacturer: Silicon Laboratories Inc
• Series: -r

Specifications of SI3068-B-FT

• Function: Direct Access Arrangement (DAA)
• Interface: *
• Number Of Circuits: 1
• Voltage - Supply: *
• Current - Supply: *
• Power (watts): *
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: *
• Package / Case: *
• Includes: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

4.4. Loop Current Sensing
The Si3068 measures loop current when off-hook. The
LCS[4:0] bits measure loop current with 3.3 mA/bit
resolution. The following functions can be performed
with the LCS bits:
LCS BITS
While off-hook, detect if a parallel phone goes on- or
off-hook.
Determine if sufficient loop current is available for
proper operation.
Detect if there is an overload condition.
30
25
20
15
10
5
0
00000
00100
0
LCS[4:0]
11111
b
b
– 00011
– 11110
13.2
b
b
b
Insufficient line current for normal operation. Use the DODI bit
(Register 4, bit 3) to determine if a line is still connected.
Normal operation.
Loop current is excessive (>160 mA).
Table 6. Loop Current Sense Transfer Function
Figure 6. Typical LCS Transfer Function
Loop Current (mA)
Rev. 1.0
4.4.1. Loop Current Measurement
When the DAA is off-hook, the LCS[4:0] bits measure
loop current with 3.3 mA/bit resolution. These bits can
be used to detect another device going off-hook by
monitoring the dc loop current. The transfer function for
LCS is shown in Figure 6 and is detailed in Table 6. The
LCS bits report loop current down to the minimum
operating loop current for the DAA. Below this
threshold, the reported value of loop current is
unpredictable and may vary between zero and the
minimum operating current.
When the LCS bits have reached their maximum value,
the Loop Current Sense Overload Interrupt bit fires;
however, LCSOI firing does not necessarily guarantee
that an overload situation has occurred.
Condition
102.3
Overload
Si3068
160
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