SI3015-FS Silicon Laboratories Inc, SI3015-FS Datasheet - Page 79

• Manufacturer Part Number: SI3015-FS
• Description: SI2400 ISOMODEM LINE-SIDE
• Manufacturer: Silicon Laboratories Inc

Specifications of SI3015-FS

• Data Format: V.90
• Interface: Serial
• Voltage - Supply: 3.3 V ~ 5 V
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Baud Rates: -

representative for further assistance in analyzing or
testing systems for this consideration.
DC Termination
The Si2400 has four programmable dc termination
modes which are selected with SF5[3:2] (DCT).
FCC mode (DCT = 10b), shown in Figure 14, 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 = 11b, shown in Figure 15, provides
current limiting while maintaining a transmit full scale
level of –1 dBm at TIP and RING. In this mode, the dc
termination will current limit before reaching 60 mA.
Japan mode DCT = 01b, shown in Figure 16, is a lower
voltage mode and supports a transmit full scale level of
Figure 15. CTR21 Mode I/V Characteristics
Figure 14. FCC Mode I/V Characteristics
20
45
40
35
30
25
15
10
5
12
11
10
.015 .02 .025 .03 .035 .04 .045 .05 .055 .06
8
9
7
6
.01 .02 .03 .04 .05 .06 .07 .08 .09 .1 .11
CTR21 DCT M ode
Loop Current (A )
Loop Current (A )
FCC DCT M ode
Rev. 1.1
–2.71 dBm. Higher transmit levels for DTMF dialing are
also supported. See "DTMF Dialing" on page 80. The
low voltage requirement is dictated by countries such as
Japan and Malaysia.
Low Voltage mode (DCT = 00b), shown in Figure 17, is
the lowest line voltage mode supported on the Si2400,
with a transmit full scale level of –5 dBm. Higher
transmit levels for DTMF dialing are also supported.
See “DTMF Dialing”. This low voltage mode is offered
for situations that require very low line voltage
operation. It is important to note that this mode should
only be used when necessary, as the dynamic range will
be significantly reduced and thus the ISOmodem will
not be able to transmit or receive large signals without
clipping them.
AC Termination
The Si2400 has two ac termination impedances,
Figure 16. Japan Mode I/V Characteristics
10.5
10.5
9.5
8.5
7.5
6.5
5.5
9.5
8.5
7.5
6.5
5.5
10
10
Figure 17. Low Voltage Mode I/V
8
8
9
7
6
9
7
6
.01 .02 .03 .04 .05 .06 .07 .08 .09 .1 .11
.01 .02 .03 .04 .05 .06 .07 .08 .09 .1 .11
Characteristics
Low V oltage M ode
Japan DCT M ode
Loop Current (A )
Loop Current (A )
Si2400
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