Si3016-KS Silicon Laboratories Inc, Si3016-KS Datasheet - Page 16

• Manufacturer Part Number: Si3016-KS
• Description: Telecom Line Management ICs Line-Side device for processors
• Manufacturer: Silicon Laboratories Inc
• Type: Chipsetr

Specifications of Si3016-KS

• Product: Modem Module
• Interface Type: Wire
• Supply Current: 0.3 mA
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-16
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Si3016
4.7. Off-Hook
The communication system generates an off-hook
command by setting the OH bit. With the OH bit set, the
system is in an off-hook state.
The off-hook state is used to seize the line for incoming/
outgoing calls and can also be used for pulse dialing.
When the DAA is on-hook, negligible dc current flows
through the hookswitch. When the DAA is placed in the
off-hook state, the hookswitch transistor pair, Q1 and
Q2, turn on. This applies a termination impedance
across TIP and RING and causes dc loop current to
flow. The termination impedance has both an ac and dc
component.
When executing an off-hook sequence, the Si3016
requires 1548/Fs seconds to complete the off-hook and
provide phone-line data on the serial link. This includes
16
LVCS[4:0]
00000
00001
11111
Table 10. Loop Current Transfer Function
Insufficient
operation. Use the DOD bit to determine if
a line is still connected.
Minimum line current for normal operation.
Loop current is excessive (overload).
Overload > 140 mA in all modes except
CTR21.
Overload > 54 mA in CTR21 mode.
LVCS
BITS
30
25
20
15
10
5
0
0
3 6
Figure 9. Typical Loop Current LVCS Transfer Function
line
9
Condition
12
15
18
current
21
24
27
30
Loop Current (mA)
33
for
CTR21
36 39 42 45 48
normal
Rev. 1.0
51
54
57
the 12/Fs filter group delay. If necessary, for the shortest
delay, a higher Fs may be established prior to executing
the off-hook, such as an Fs of 10.286 kHz. The delay
allows for line transients to settle prior to normal use.
4.8. DC Termination
The Si3016 has four programmable dc termination
modes that are selected with the DCT[1:0] bits in
Register 16.
FCC mode (DCT[1:0] = 10 b), shown in Figure 10, is the
default dc termination mode and supports a transmit full
scale level of –1 dBm at TIP and RING. This mode
meets FCC requirements in addition to the requirements
of many other countries.
CTR21 mode (DCT[1:0] = 11 b), shown in Figure 11,
60
63
Figure 10. FCC Mode I/V Characteristics
66
69
12
10
11
6
9
7
72
8
.01 .02 .03 .04 .05 .06 .07 .08 .09 .1 .11
75 78 81 84 87 90 93
Loop Current (A)
Overload
FCC DCT Mode
140