Si2400
V. 22
B I S
I S O
M O D E M
®
W I T H
I
N T E G R A T E D
G
L O B A L
D A A
Features
i2
40
0
S
Data Modem Formats
2400 bps: V.22bis
1200 bps: V.22, V.23, Bell 212A
300 bps: V.21, Bell 103
Fast Connect and V.23 Reversing
SIA and other security protocols
Integrated DAA
Capacitive Isolation
Parallel Phone Detect
Globally Compliant Line Interface
Overcurrent Detection
Caller ID Detection and Decode
DTMF Tone Gen./Detection
3.3 V or 5.0 V Power
UART with Flow Control
AT Command Set Support
Integrated Voice Codec
PCM Data Pass-Through Mode
HDLC Framing in Hardware
Call Progress Support
Pb-Free/RoHS-Compliant
Packages Available
Ordering Information
See page 90.
Pin Assignments
Si2400
Applications
Set Top Boxes
Power Meters
Security Systems
ATM Terminals
Medical Monitoring
Point-of-Sale
XTALI
XTALO
CLKOUT
V
D
RXD*
TXD*
CTS
RESET
1
2
3
4
5
6
7
8
S
16
15
14
13
12
11
10
9
EOFR/GPIO1
CD/AIN/GPIO2
ESC/GPIO3
ISOB
GND
C1A
ALERT/GPIO4
AOUT
Description
The Si2400 ISOmodem® is a complete modem chipset with integrated
direct access arrangement (DAA) that provides a programmable line
interface to meet global telephone line requirements. Available in two 16-
pin small outline (SOIC) packages, it eliminates the need for a separate
DSP data pump, modem controller, analog front end (AFE), isolation
transformer, relays, opto-isolators, 2- to 4-wire hybrid, and voice codec.
The Si2400 is ideal for embedded modem applications due to its small
board space, low power consumption, and global compliance.
Si3015
QE2
DCT
IGND
C1B
RNG1
RNG2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
FILT2
FILT
RX
REXT
REXT2
REF
VREG2
VREG
Functional Block Diagram
Si2400
RXD
TXD
Si3015
RX
QB
QE
UART
MUX
μ
Controller
(AT Decoder
Call Progress)
Isolation Interface
RESET
EO FR/G PIO 1
CD/AIN/G PIO 2
ESC/G PIO 3
ALERT/G PIO 4
CTS
Audio
Codec
Clock
Interface
Control
Interface
DSP
(Data Pump)
Isolation Interface
Hybrid
and
DC
Termination
FILT
FILT2
REF
DCT
VREG
VREG2
REXT
REXT2
RNG 1
RNG 2
QB
QE
QE2
Patents pending
Ring Detect
O ff-Hook
CLKOUT
XTALI
XTALO
AOUT
Rev. 1.3 8/06
Copyright © 2006 by Silicon Laboratories
i3
01
5
Si2400
Si2400
T
A B L E O F
C
O N T E N TS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4. Analog Input/Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.1. Digital Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2. Configurations and Data Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.3. Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.4. Global DAA Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.5. Parallel Phone Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.6. Loop Current Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.7. Carrier Detect/Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.8. Overcurrent Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.9. Caller ID Decoding Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
5.10. Tone Generation and Tone Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
5.11. PCM Data Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.12. Analog Codec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.13. V.23 Operation/V.23 Reversing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.14. V.42 HDLC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5.15. Fast Connect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5.16. Clock Generation Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6. AT Command Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
6.1. Command Line Execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.2. < CR > End Of Line Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.3. AT Command Set Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
6.4. S-Register Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
6.5. Alarm Industry AT Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.6. Modem Result Codes and Call Progress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
7. Low Level DSP Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
7.1. DSP Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
7.2. Call Progress Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8. S Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Appendix A—DAA Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Appendix B—Typical Modem Applications Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Appendix C—UL1950 3rd Edition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
9. Pin Descriptions: Si2400 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
10. Pin Descriptions: Si3015 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
11. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
12. Package Outline: 16-Pin SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
Rev. 1.3
3
Si2400
1. Electrical Specifications
Table 1. Recommended Operating Conditions
Parameter
1
Ambient Temperature
Ambient Temperature
Si2400 Supply Voltage, Digital
3
Symbol
T
A
T
A
V
D
Test Condition
K-Grade
B-Grade
Min
2
0
–40
3.0
Typ
25
25
3.3/5.0
Max
2
70
85
5.25
Unit
°C
°C
V
Notes:
1.
The Si2400 specifications are guaranteed when the typical application circuit (including component tolerance) and any
Si2400 and any Si3015 are used. See Figure 3 on page 10 for a typical application circuit.
2.
All minimum and maximum specifications are guaranteed and apply across the recommended operating conditions. Typical
values apply at nominal supply voltages and an operating temperature of 25 °C unless otherwise stated.
3.
The digital supply, V
D
, can operate from either 3.3 V or 5.0 V. The Si2400 interface supports 3.3 V logic when operating
from 3.3 V. The 3.3 V operation applies to both the serial port and the digital signals CTS, CLKOUT, GPIO1–4, and RESET.
4
Rev. 1.3
Si2400
Table 2. Loop Characteristics
(V
D
= 3.0 to 5.25 V, T
A
= 0 to 70°C for K-Grade and –40 to 85°C for B-Grade, See Figure 1)
Parameter
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
DC Termination Voltage
Symbol
V
TR
V
TR
V
TR
V
TR
V
TR
V
TR
V
TR
V
TR
V
TR
Test Condition
I
L
= 20 mA, ACT
1
= 1
b
DCT = 11
b
(CTR21)
I
L
= 42 mA, ACT = 1
b
DCT = 11
b
(CTR21)
I
L
= 50 mA, ACT = 1
b
DCT = 11
b
(CTR21)
I
L
= 60 mA, ACT = 1
b
DCT = 11
b
(CTR21)
I
L
= 20 mA, ACT = 0
b
DCT = 01
b
(Japan)
I
L
= 100 mA, ACT = 0
b
DCT = 01
b
(Japan)
I
L
= 20 mA, ACT = 0
b
DCT = 10
b
(FCC)
I
L
= 100 mA, ACT = 0
b
DCT = 10
b
(FCC)
I
L
= 15 mA, ACT = 0
b
DCT = 00
b
(Low Voltage)
V
TR
= –48V
FCC/Japan Modes
CTR21 Mode
DC current flowing
through ring detection
circuitry
Min
—
—
—
40
—
9
—
9
—
Typ
—
—
—
—
—
—
—
—
—
Max
7.5
14.5
40
—
6.0
—
7.5
—
5.2
Unit
V
V
V
V
V
V
V
V
V
On Hook Leakage Current
2
Operating Loop Current
Operating Loop Current
DC Ring Current
2
I
LK
I
LP
I
LP
—
13
13
—
—
—
—
—
7
120
60
7
µA
mA
mA
µA
Ring Detect Voltage
3
Ring Detect Voltage
3
Ring Frequency
4
Ringer Equivalence Number
5
V
RD
V
RD
F
R
REN
RT = 0
b
RT = 1
b
11
17
15
—
—
—
—
—
22
33
68
0.2
V
RMS
V
RMS
Hz
Notes:
1.
SF[4] (ACT); SF5[3:2] (DCT); SF5[0] (RT).
2.
R25 and R26 installed.
3.
The ring signal is guaranteed to not be detected below the minimum. The ring signal is guaranteed to be detected
above the maximum.
4.
The Si2400 ring detector can be programmed to detect rings between this range.
5.
C15, R14, Z2, and Z3 not installed. SF5[1] (RZ) = 0
b
. See "Ringer Impedance" on page 80.
Rev. 1.3
5