Si2457 34 15 04D

Si2457/34/15/04
V.90, V.34, V. 32 B IS , V.22 B IS I SO MO DE M ®
WITH
G L O B A L DAA
Features
This data sheet applies to Si2457/34/  Integrated DAA
15/04 Revision D
Over 6000 V capacitive
isolation
 Data modem formats

Parallel
phone detect
line
interface
Overcurrent detection
ITU-T,
Bell
bps up to 56 kbps
V.21,V.22, V.29 Fast Connect
V.44, V.42, V.42bis, MNP2-5
Automatic rate negotiation
Globally-compliant
300

Type I and II caller ID decode
No external ROM or RAM required
 UART, SPI, or parallel interface
 Flexible clock options




32.768 kHz oscillator
4.915 MHz oscillator
27 MHz clock input


Low-cost


AT command set support
SMS / MMS support
Firmware upgradeable
EEPROM interface
Lead-free, RoHS-compliant
packages
Commercial or industrial
temperature range
DTMF detection/generation
Ordering Information
This data sheet is valid only for
those chipset combinations listed
on page 50.
Pin Assignments
Applications
Set-top boxes
 Point-of-sale terminals
 Text / video telephones
Si2457/34/15/04
(16-Pin Option)
Digital video recorder
 Digital televisions
 Remote monitoring


Description
The ISOmodem® family of products is a complete modem ranging in speed
from 56,000 bps to 2400 bps. Offered as a chipset with the Si2457, Si2434,
Si2415, or Si2404 system-side device and the Si3018/10 line-side device,
the ISOmodem utilizes Silicon Laboratories’ patented direct access
arrangement (DAA) technology to provide a programmable telephone line
interface with an unparalleled level of integration. These compact solutions
eliminate the need for a separate DSP, modem controller, codec,
transformer, relay, opto-isolators, clocking crystal, and 2-4 wire hybrid.
Available with a system-side packaging option of either a 16-pin SOIC or a
24-pin TSSOP, these devices are ideal for embedded modem applications
due to their flexibility, small footprint, and minimal external component
count.
CLKIN/XTALI
1
16
SS/RTS
XTALO
RI
VD
2
15
DCD
3
4
14
13
MISO/RXD
MOSI/TXD
SCLK/CTS
RESET
5
6
7
12
11
ESC
VA
GND
INT
10
9
C1A
C2A
8
Si2457/34/15/04
(24-Pin Option)
CLKIN/XTALI
1
24
SDO/EECLK/D5
XTALO
CLKOUT/EECS/A0
2
3
23
22
DCD/D4
ESC/D3
FSYNC/D6
4
21
VD3.3
GND
5
6
20
19
VD3.3
GND
VDB
VDA
7
18
SDI/EESD/D2
SS/RTS/D7
8
RI/D1
INT/DO
AOUT/INT
MOSI/TXD/WR
9
10
17
16
15
SCLK/CTS/CS
11
14
C1A
RESET
12
13
C2A
MISO/RXD/RD
System Block Diagram
Si3018/10
QE
DCT
Host
CPU
Host Interface
 UART
 SPI
 Parallel
Rev. 1.3 12/10
Si24xx
System
Side
Si3018
Line
Side
Global
DAA
BOM
Telco
Tip
Ring
1
RX
IB
2
3
4
C1B
C2B
VREG
5
6
7
RNG1
8
16
15
DCT2
14
13
DCT3
QB
QE2
12
11
10
9
IGND
SC
VREG2
RNG2
Capacitive
Isolation Barrier
Copyright © 2010 by Silicon Laboratories
Si2457/34/15/04
Si2457/34/15/04
2
Rev. 1.3
Si2457/34/15/04
TA B L E
OF
C O N T E N TS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3. Bill of Materials: Si2457/34/15/04 Chipset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1. Host Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.2. Command Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3. Data Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.4. Fast Connect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.5. V.80 Synchronous Access Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.6. Clocking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.7. Low-Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.8. Data Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.9. Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.10. Wire Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.11. Caller ID Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.12. Parallel Phone Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.13. Overcurrent Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.14. Global Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.15. Firmware Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.16. DTMF Detection / Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.17. SMS/MMS Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.18. Codec Interface (24-Pin Version Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.19. EEPROM Interface (24-Pin Version Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.20. AT Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.21. Extended AT Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5. S-Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6. User-Access Registers (U-Registers) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
7. Pin Descriptions: Si2457/34/15/04 (16-Pin Option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
8. Pin Descriptions: Si2457/34/15/04 (24-Pin Option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
9. Pin Descriptions: Si3018/10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
10. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
11. Package Markings (Top Markings) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
11.1. Si2457-D-FT Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
11.2. Si2457-D-FS Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
11.3. Si2434-D-FT Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
11.4. Si2434-D-FS Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.5. Si2415-D-FT Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.6. Si2415-D-FS Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.7. Si2404-D-FT Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.8. Si2404-D-FS Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
11.9. Si3010-F-FS Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
11.10. Si3018-F-FS Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
12. Package Outline: 24-Pin TSSOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
13. 24-Pin TSSOP Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
14. Package Outline: 16-Pin SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
15. 16-Pin SOIC Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Rev. 1.3
3
Si2457/34/15/04
1. Electrical Specifications
Table 1. Recommended Operating Conditions
Symbol
Test Condition
Min2
Typ
Max2
Unit
Ambient Temperature
TA
F-grade
G-grade
0
–40
25
25
70
85
°C
Si2457/34/15/04 Supply Voltage,
Digital3
VD
3.0
3.3
3.6
V
Parameter1
Notes:
1. The Si2457/34/15/04 specifications are guaranteed when the typical application circuit (including component tolerance)
and any Si2457/34/15/04 and any Si3018 are used. See "2. Typical Application Schematic" on page 11.
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, VD, operates from 3.0 to 3.6 V.
Table 2. Loop Characteristics
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for F-grade, TA = –40 to 85 °C for G-grade)
Parameter
Symbol
DC Termination Voltage
VTR
DC Termination Voltage
VTR
DC Termination Voltage
VTR
DC Termination Voltage
VTR
DC Termination Voltage
VTR
DC Termination Voltage
VTR
DC Termination Voltage
VTR
On-Hook Leakage Current
Operating Loop Current
Operating Loop Current
DC Ring Current
ILK
ILP
ILP
Ring Detect Voltage2
Ring Detect Voltage2
Ring Frequency
Ringer Equivalence Number
VRD
VRD
FR
REN
Test Condition
1
IL = 20 mA, ILIM = 0
DCV = 00, MINI = 11, DCR = 0
IL = 120 mA, ILIM = 0
DCV = 00, MINI = 11, DCR = 0
IL = 20 mA, ILIM = 0
DCV = 11, MINI = 00, DCR = 0
IL = 120 mA, ILIM = 0
DCV = 11, MINI = 00, DCR = 0
IL = 20 mA, ILIM = 1
DCV = 11, MINI = 00, DCR = 0
IL = 60 mA, ILIM = 1
DCV = 11, MINI = 00, DCR = 0
IL = 50 mA, ILIM = 1
DCV = 11, MINI = 00, DCR = 0
VTR = –48 V
MINI = 00, ILIM = 0
MINI = 00, ILIM = 1
DC current flowing through ring
detection circuitry
RT = 0
RT = 1
Min
Typ
Max
Unit
—
—
6.0
V
9
—
—
V
—
—
7.5
V
9
—
—
V
—
—
7.5
V
40
—
—
V
—
—
40
V
—
10
10
—
—
—
—
1.5
5
120
60
3
µA
mA
mA
µA
12
18
15
—
15
21
—
—
18
25
68
0.2
VRMS
VRMS
Hz
Notes:
1. ILIM = U67, bit 9; DCV = U67, bits 3:2; MINI = U67, bits 13:12; DCR = U67, bit 7; RT = U67, bit 0.
2. The ring signal is guaranteed to not be detected below the minimum. The ring signal is guaranteed to be detected
above the maximum.
4
Rev. 1.3
Si2457/34/15/04
TIP
+
600 
Si3018
IL
VTR
10 µF
RING
–
Figure 1. Test Circuit for Loop Characteristics
Table 3. DC Characteristics, VD = 3.0 to 3.6 V
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for F-grade, TA = –40 to 85 °C for G-grade)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
High Level Input Voltage
VIH
2.0
—
—
V
Low Level Input Voltage
VIL
—
—
0.8
V
High Level Output Voltage
VOH
IO = –2 mA
2.4
—
—
V
Low Level Output Voltage
VOL
IO = 2 mA
—
—
0.35
V
Input Leakage Current
IL
–10
—
10
µA
Pullup Resistance Pins
RPU
50
125
200
k
ID
—
17
35
mA
ID
—
4.4
—
mA
—
80
—
µA
Total Supply Current*
Total Supply Current, Wake on Ring*
Total Supply Current, Powerdown
*
ID
PDN = 1
*Note: All inputs at 0 or VD. All inputs held static except clock and all outputs unloaded (Static IOUT = 0 mA).
Rev. 1.3
5
Si2457/34/15/04
Table 4. AC Characteristics
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for F-grade, Fs = 8 kHz, TA = –40 to 85 °C for G-grade)
Parameter
Symbol
Sample Rate
Test Condition
Fs
Clock Input Frequency
FXTL
default
Min
Typ
Max
Unit
—
8
—
kHz
—
4.9152
—
MHz
Mode1
—
27
—
MHz
Clock Input Frequency
FXTL
27 MHz
Clock Input Frequency
FXTL
32 kHz Mode1
—
32.768
—
kHz
Receive Frequency Response
Low –3 dBFS Corner, FILT = 0
—
5
—
Hz
Receive Frequency Response
Low –3 dBFS Corner, FILT = 1
—
200
—
Hz
VFS
—
1.1
—
VPEAK
Receive Full Scale Level2,3
VFS
—
1.1
—
VPEAK
Dynamic Range4
DR
ILIM = 0, DCV = 11, MINI = 00
DCR = 0, IL = 100 mA
—
80
—
dB
Dynamic Range4
DR
ILIM = 0, DCV = 00, MINI = 11
DCR = 0, IL = 20 mA
—
80
—
dB
Dynamic Range4
DR
ILIM = 1, DCV = 11, MINI = 00
DCR = 0, IL = 50 mA
—
80
—
dB
Transmit Total Harmonic Distortion5
THD
ILIM = 0, DCV = 11, MINI = 00
DCR = 0, IL = 100 mA
—
–72
—
dB
Transmit Total Harmonic Distortion5
THD
ILIM = 0, DCV = 00, MINI = 11
DCR = 0, IL = 20 mA
—
–78
—
dB
Receive Total Harmonic Distortion5
THD
ILIM = 0, DCV = 00, MINI = 11
DCR = 0, IL = 20 mA
—
–78
—
dB
Receive Total Harmonic Distortion5
THD
ILIM = 1,DCV = 11, MINI=00
DCR = 0, IL = 50 mA
—
–78
—
dB
DRCID
VIN = 1 kHz, –13 dBm
—
50
—
dB
Transmit Full Scale
Level2
Dynamic Range (Caller ID Mode)
Notes:
1. Refer to “AN93: ISOmodem® Chipset Family Designer's Guide” for configuring clock input reset strapping.
2. Measured at TIP and RING with 600 termination at 1 kHz, as shown in Figure 1 on page 5.
3. Receive full scale level produces –0.9 dBFS at DTX.
4. DR = 20 x log |Vin| + 20 x log (rms signal/rms noise). Applies to both transmit and receive paths. Vin = 1 kHz, –3 dBFS.
5. Vin = 1 kHz, –3 dBFS. THD = 20 x log (rms distortion/rms signal).
6
Rev. 1.3
Si2457/34/15/04
Table 5. Absolute Maximum Ratings
Parameter
Symbol
Value
Unit
DC Supply Voltage
VD
4.1
V
Input Current, Si2457/34/15/04 Digital
Input Pins
IIN
±10
mA
Digital Input Voltage
VIND
–0.3 to (VD + 0.3)
V
CLKIN/XTALI Input Voltage
VXIND
–0.3 to (VD + 0.3)
V
TA
–10 to 100
°C
TSTG
–40 to 150
°C
Operating Temperature Range
Storage Temperature Range
Note: Permanent device damage may occur if the above absolute maximum ratings are exceeded. Functional operation
should be restricted to the conditions as specified in the operational sections of this data sheet. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Table 6. Switching Characteristics1
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for F-grade, TA = –40 to 85 °C for G-grade)
Parameter
Symbol
Min
Typ
Max
Unit
tBD
–1
—
1
%
RESET to RESET
tRS
5.02
—
—
ms
RESET to 1st AT Command
tAT
300
—
—
ms
Address Setup
tAS
15
—
—
ns
Address Hold
tAH
0
—
—
ns
WR Low Pulse Width
tWL
50
—
—
ns
tWDSU
20
—
—
ns
Write Cycle Time
tWC
120
—
—
ns
Chip Select Setup
tCSS
10
—
—
ns
Chip Select Hold
tCSH
0
—
—
ns
tRL
50
—
—
ns
tRLDD
—
—
20
ns
Data Hold
tDH
10
—
—
ns
RD High to Hi-Z Time
tDZ
—
—
30
ns
UART Timing Parameters
Baud Rate Accuracy
Reset Timing Parameters
Parallel Timing Parameters
Write Data Setup Time
RD Low Pulse Width
RD Low to Data Driven Time
Notes:
1. All timing is referenced to the 50% level of the waveform. Input test levels are VIH = VD – 0.4 V, VIL = 0.4 V.
2. With 32.768 kHz clocking, allow 500 ms for the reset low-to-high minimum pulse on power-up and wake-from-powerdown conditions.
Rev. 1.3
7
Si2457/34/15/04
Table 6. Switching Characteristics1 (Continued)
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for F-grade, TA = –40 to 85 °C for G-grade)
Parameter
Symbol
Min
Typ
Max
Unit
tRC
120
—
—
ns
tWRC
120
—
—
ns
Read Cycle Time
Write to Read Cycle Time
Serial Peripheral Interface (SPI) Timing Parameters
SS Falling to First SCLK Edge
tSE
41
—
—
ns
Last SCLK Edge to SS Rising
tSD
41
—
—
ns
SS Rising to MISO High-Z
tSDZ
—
—
93
ns
SCLK High Time
tCKH
102
—
—
ns
SCLK Low Time
tCKL
102
—
—
ns
MOSI Valid to SCLK Sample Edge
tSIS
41
—
—
ns
SCLK Sample Edge to MOSI Change
tSIH
41
—
—
ns
SCLK Shift Edge to MISO Change
tSOH
—
—
93
ns
SCLK cycle time
tSCK
224
—
—
ns
tNSS_INACT
81
—
—
ns
Inactive time between SS actives
Notes:
1. All timing is referenced to the 50% level of the waveform. Input test levels are VIH = VD – 0.4 V, VIL = 0.4 V.
2. With 32.768 kHz clocking, allow 500 ms for the reset low-to-high minimum pulse on power-up and wake-from-powerdown conditions.
SS
T
T
SE
T
CKL
SD
SCLK*
T
CKH
T
T
SIS
SIH
MOSI
T
SEZ
T
T
SOH
SDZ
MISO
Figure 2. SPI Slave Timing
8
Rev. 1.3
Si2457/34/15/04
t CSS
t CSH
t AS
t AH
CS
ADDRESS = 0 or 1
A0
t RL
t RC
RD
t DZ
t RLDD
t DH
D[7:0]
VALID DATA
VALID DATA
t RLDD
Figure 3. Parallel Interface Read Timing
t CSS
t CSH
t AS
t AH
CS
A0
ADDRESS = 0 or 1
tW L
tW C
WR
t W DSU
t DH
D[7:0]
VALID DATA
VALID DATA
Figure 4. Parallel Interface Write Timing
Rev. 1.3
9
Si2457/34/15/04
CS
A0
ADDRESS = 0 or 1
WR
tWRC
RD
tWDSU
D[7:0]
tDH
VALID DATA
VALID DATA
tRLDD
Figure 5. Parallel Interface Write Followed by Read Timing
10
Rev. 1.3
RESET_
RXD
TXD
CTS_
8
5
6
7
16
15
14
11
3
RESET
RXD
TXD
CTS
RTS
DCD
ESC
INT
GPIO
C51
C2A
C1A
XTALO
CLKIN/XTALI
GND
12
RTS_
DCD_
ESC
INT_
GPIO
4
VD
VA
13
9
Rev. 1.3
C41
R13
R12
Y1
R9
C5
C2
C1
C6
10
7
4
6
5
VREG2
VREG
IB
C2B
C1B
U2
RNG1
RNG2
QE
QE2
QB
DCT2
DCT3
DCT
RX
8
9
1
12
13
16
14
2
3
C4
R1
Q5
R2
R11
R10
C7
Q4
R4
R7
R8
R5
Q1
Z1
R3
Q2
Q3
C10
R6
+
D1
C3
-
FB1
FB2
C9
C8
R15
R16
Emissions option
TIP
RV1
RING
Refer to AN93 Appendix A for layout guidelines.
Please submit layout to Silicon Labs for review
prior to PCB fabrication.
Figure 6. Typical Si2457/34/15/04 Schematic with 16-pin System-Side Option
10
2
1
C40
External crystal option
1
2
U1
IGND
15
C50
SC
+
11
VDD
Si2457/34/15/04
2. Typical Application Schematic
11
RESET_
RXD
TXD
CTS_
8
5
6
7
16
15
14
11
3
RESET
RXD
TXD
CTS
RTS
DCD
ESC
INT
GPIO
C51
C2A
C1A
XTALO
CLKIN/XTALI
GND
12
RTS_
DCD_
ESC
INT_
GPIO
4
VD
VA
13
Rev. 1.3
C41
C40
R13
R12
Y1
R9
C5
C2
C1
C6
10
7
4
6
5
VREG2
VREG
IB
C2B
C1B
U2
RNG1
RNG2
QE
QE2
QB
DCT2
DCT3
DCT
RX
8
9
1
12
13
16
14
2
3
C4
R1
Q5
R2
R11
R10
C7
Q4
R4
R7
R8
R5
Q1
Z1
R3
Q2
Q3
C10
R6
+
D1
C3
-
FB1
FB2
C9
C8
R15
R16
Emissions option
TIP
RV1
RING
Refer to AN93 Appendix A for layout guidelines.
Please submit layout to Silicon Labs for review
prior to PCB fabrication.
Figure 7. Typical Si2457/34/15/04 Schematic with 24-pin System-Side Option
9
10
2
1
External crystal option
1
2
U1
IGND
15
C50
SC
12
+
11
VDD
Si2457/34/15/04
Si2457/34/15/04
3. Bill of Materials: Si2457/34/15/04 Chipset
Component
Value
Supplier(s)
C1, C2
33 pF, Y2, X7R, ±20%
Panasonic, Murata, Vishay
C3
10 nF, 250 V, X7R, ±20%
Venkel, SMEC
1.0 µF, 50 V, Elec/Tant, ±20%
Panasonic
C4
C5, C6, C50, C52
1
0.1 µF, 16 V, X7R, ±20%
Venkel, SMEC
C7
2.7 nF, 50 V, X7R, ±20%
Venkel, SMEC
C8, C9
680 pF, Y2, X7R, ±10%
Panasonic, Murata, Vishay
C10
0.01 µF, 16 V, X7R, ±20%
Venkel, SMEC
C40
C41
4.9152 MHz: 33 pF, 16 V, NPO, ±5%
32.768 kHz: 18 pF, 16 V, NPO, ±5%
27 MHz: Not Populated
1
C51, C53
D1, D2
Venkel, SMEC
2
0.22 µF, 16 V, X7R, ±20%
Venkel, SMEC
Dual Diode, 225 mA, 300 V, CMPD2004S
Central Semiconductor
FB1, FB2
Ferrite Bead, BLM21AG601SN1
Murata
Q1, Q3
NPN, 300 V, MMBTA42
OnSemi, Fairchild
Q2
PNP, 300 V, MMBTA92
OnSemi, Fairchild
Q4, Q5
NPN, 80 V, 330 mW, MMBTA06
OnSemi, Fairchild
RV1
Sidactor, 275 V, 100 A
Teccor, Protek, ST Micro
R1
1.07 k, 1/2 W, 1%
Venkel, SMEC, Panasonic
R2
150 , 1/16 W, 5%
Venkel, SMEC, Panasonic
R3
3.65 k, 1/2 W, 1%
Venkel, SMEC, Panasonic
R4
2.49 k, 1/2 W, 1%
Venkel, SMEC, Panasonic
R5, R6
100 k, 1/16 W, 5%
Venkel, SMEC, Panasonic
R7, R8
20 M, 1/16 W, 5%
Venkel, SMEC, Panasonic
R9
1 M, 1/16 W, 1%
Venkel, SMEC, Panasonic
R10
536 , 1/4 W, 1%
Venkel, SMEC, Panasonic
R11
73.2 , 1/2 W, 1%
Venkel, SMEC, Panasonic
56 , 1/16 W, 1%
Venkel, SMEC, Panasonic
R15, R16
0 , 1/16 W
Venkel, SMEC, Panasonic
U1
Si2457/34/15/04
Silicon Labs
U2
Si3018/10
Silicon Labs
R12, R13
3
32.768 kHz, 12 pF, 100 ppm, 35 k max ESR
4
Y1
4.9152 MHz, 20 pF, 100 ppm, 150  ESR
ECS Inc., Siward
27 MHz (from external clock)
Z1
Zener Diode, 43 V, 1/2 W, BZT84C43
On Semi
Notes:
1. C52 and C53 should not be populated with the Si2457/34/15/04 16-pin package option.
2. Several diode bridge configurations are acceptable. For example, a single DF04S or four 1N4004 diodes may be used.
3. Murata BLM21AG601SN1 may be substituted for R15–R16 (0 ) to decrease emissions.
4. To ensure compliance with ITU specifications, frequency tolerance must be less than 100 ppm including initial
accuracy, 5-year aging, 0 to 70 °C, and capacitive loading.
Rev. 1.3
13
Si2457/34/15/04
Table 7. Protocol Characteristics
Item
Specification
Data Rate
56 kbps1
54.666 kbps1
53.333 kbps1
52 kbps1
50.666 kbps1
49.333 kbps1
48 kbps1
46.666 kbps1
45.333 kbps1
44 kbps1
42.666 kbps1
41.333 kbps1
40 kbps1
38.666 kbps1
37.333 kbps1
36 kbps1
34.666 kbps1
33.333 kbps1
32 kbps1
30.666 kbps1
29.333 kbps1
28 kbps1
33.6 kbps2
31.2 kbps2
28.8 kbps2
26.4 kbps2
24.0 kbps2
21.6 kbps2
19.2 kbps2
16.8 kbps2
14.4 kbps3
12.0 kbps3
9600 bps3
7200 bps3
4800 bps3
2400 bps
1200 bps
300 bps
300 bps
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.901
ITU-T V.342
ITU-T V.342
ITU-T V.342
ITU-T V.342
ITU-T V.342
ITU-T V.342
ITU-T V.342
ITU-T V.342
ITU-T V.34 or V.32bis3
ITU-T V.34 or V.32bis3
ITU-T V.34, V.32bis, or V.293
ITU-T V.34 or V.32bis3
ITU-T V.34 or V.32bis3
ITU-T V.34 or V.22bis3
ITU-T V.22bis, V.23, or Bell 212A
ITU-T V.21
Bell 103
Notes:
1. Supported on Si2457 only.
2. Supported on Si2457 and Si2434 only.
3. Supported on Si2457, Si2434, and Si2415 only.
14
Rev. 1.3
Si2457/34/15/04
Table 7. Protocol Characteristics (Continued)
Item
Data Format
Bit asynchronous
Compatibility
Specification
Selectable 8, 9, 10, or 11 bits per character, which includes
the start, stop, and parity bits
ITU-T V.901, V.342, V.32bis, V.32, V.23, V.22bis, V.22, V.21,
Bell 212A, and Bell 103
Operating Mode
Switched network
Two-wire full duplex
Data Modulation
28 to 56 kbps1
2.4 to 33.6 kbps2
14.4 kbps3
12.0 kbps3
9600 bps3
9600 bps3
9600 bps3
7200 bps3
4800 bps3
2400 bps
1200 bps
300 bps
V.90 as specified by ITU-T
V.34 as specified by ITU-T
128-level TCM/2400 Baud ±0.01%
64-level TCM/2400 Baud ±0.01%
32-level TCM/2400 Baud ±0.01%
16-level QAM/2400 Baud ±0.01%
V.29 QAM as specified by ITU-T
16-level TCM/2400 Baud ±0.01%
4-level QAM/2400 Baud ±0.01%
16-level QAM/600 Baud ±0.01%
4-level PSK/600 Baud ±0.01%
FSK 300 Baud ±0.01%
Answer Tone
ITU-T V.32bis, V.32, V.22bis, V.22, and V.21
modes
Bell 212A and 103 modes
Transmit Carrier
V.901
V.342
ITU-T V.32bis3
ITU-T V.323
ITU-T V.293
ITU-T V.22, V.22bis/Bell 212A
Originate mode
Answer mode
ITU-T V.21
Originate mode
Answer mode
Bell 103
Originate mode
Answer mode
2100 Hz ±3 Hz
2225 Hz ±3 Hz
As specified by ITU-T
As specified by ITU-T
1800 Hz ±0.01%
1800 Hz ±0.01%
1700 Hz±1 Hz
1200 Hz ±0.5 Hz
2400 Hz ±1 Hz
Mark (980 Hz ±12 Hz) Space (1180 Hz ±12 Hz)
Mark (1650 Hz ±12 Hz) Space (1850 Hz ±12 Hz)
Mark (1270 Hz ±12 Hz) Space (1070 Hz ±12 Hz)
Mark (2225 Hz ±12 Hz) Space (2025 Hz ±12 Hz)
Output Level
Permissive—Switched network
–9 dBm maximum
Notes:
1. Supported on Si2457 only.
2. Supported on Si2457 and Si2434 only.
3. Supported on Si2457, Si2434, and Si2415 only.
Rev. 1.3
15
Si2457/34/15/04
Table 7. Protocol Characteristics (Continued)
Item
Receive Carrier
ITU-T V.901
ITU-T V.342
ITU-T V.32bis3
ITU-T V.323
ITU-T V.293
ITU-T V.22, V.22bis/Bell 212A
Originate mode
Answer mode
ITU-T V.21
Originate mode
Answer mode
Bell 103
Originate mode
Answer mode
Specification
As specified by ITU-T
As specified by ITU-T
1800 Hz ±7 Hz
1800 Hz ±7 Hz
1700 Hz ±7 Hz
2400 Hz ±7 Hz
1200 Hz ±7 Hz
Mark (980 Hz ±12 Hz) Space (1180 Hz ±12 Hz)
Mark (1650 Hz ±12 Hz) Space (1850 Hz ±12 Hz)
Mark (2225 Hz ±12 Hz) Space (2025 Hz ±12 Hz)
Mark (1270 Hz ±12 Hz) Space (1070 Hz ±12 Hz)
Carrier Detect (level for ITU-T V.22bis, V.22, V.21,
212, 103) in Switched Network
Acquisition (–43 dBm)
Release (–48 dBm)
Hysteresis
2 dBm minimum
Note: ITU-T V.901, V.342, V.32/V.32bis3 are echo canceling protocols that use signal quality as criteria for maintaining
connection. They also provide for self-training detection to force disconnect.
DTE Interface
EIA/TIA-232-E (ITU-T V.24/V.28/ISO 2110)
Line Equalization
Automatic Adaptive
Connection Options
Loss of Carrier in ITU-T V.22bis and lower
Phone Types
500 (rotary dial), 2500 (DTMF dial)
Dialing
Pulse and Tone
DTMF Output Level
Per TIA-968-B
Pulse Dial Ratio
Make/Break: 39/61%
Ring Cadence
Per T1.401.02-2000
Call Progress Monitor
BUSY
CONNECT (rate)
NO ANSWER
NO CARRIER
NO DIALTONE
OK
RING
RINGING
Notes:
1. Supported on Si2457 only.
2. Supported on Si2457 and Si2434 only.
3. Supported on Si2457, Si2434, and Si2415 only.
16
Rev. 1.3
Si2457/34/15/04
4. Functional Description
XTI
CS
WR
RD
A0
D0-D7
MISO
MOSI
SCLK
SS
UART
Interface
Data Bus
C1
DAA
Interface
C2
Si3018/10
EEPROM
Interface
DSP
EESD
EECLK
EECS
RXD
TXD
CTS
RTS
DCD
ESC
RI
XTO
PLL
Clocking
Controller
CLKOUT
To Phone
Line
AOUT
Parallel
Interface
ROM
Program Bus
This device is ideal for embedded modem applications
due to its small board space, low power consumption,
and global compliance. The Si2457/34/15/04 solution
includes a silicon DAA using Silicon Laboratories’
proprietary third-generation DAA technology. This highlyintegrated DAA can be programmed to meet worldwide
PTT specifications for ac termination, dc termination,
ringer impedance, and ringer threshold. In addition, the
Si2457/34/15/04 has been designed to meet the most
stringent worldwide requirements for out-of-band energy,
billing-tone immunity, surge immunity, and safety
requirements.
The Si2457/34/15/04 allows for rapid integration into
existing modem applications by providing a serial
interface that can directly communicate to either a
microcontroller via a UART interface or a PC via an RS232 port. This interface allows for PC evaluation of the
modem immediately upon powerup via the AT
commands using standard terminal software.
RAM
SPI
Interface
INT
RESET
Figure 8. Functional Block Diagram
The Si2457/34/15/04 ISOmodem® is a complete
embedded modem chipset with integrated direct access
arrangement (DAA) that provides a programmable line
interface to meet global telephone line requirements.
Available in two small packages, this solution includes a
DSP data pump, modem controller, on-chip RAM and
ROM, codec, DAA, analog output, and 27 MHz clock
input.
The Si2457/34/15/04 accepts standard modem AT
commands and provides connect rates up to 56/33.6/
14.4/2.4 kbps full-duplex over the Public Switched
Telephone Network (PSTN). The Si2457/34/15/04
features a complete set of modem protocols including all
ITU-T standard formats up to V.90.
To provide the most flexibility, the Si2457/34/15/04
ISOmodem system-side device is offered in either a 24pin TSSOP or a 16-pin SOIC package. The 16-pin
version is footprint-compatible with the Si2401
ISOmodem and is recommended for most applications.
The 16-pin version does not support the parallel,
EEPROM or voice codec interface. If these features are
required, customers should use the 24-pin version.
The ISOmodem provides numerous additional features
for embedded modem applications. The modem includes
full type I and type II caller ID detection and decoding for
global standards. Call progress monitoring is supported
through standard result codes. The modem is also
programmable to meet global settings. Because the
Si2457/34/15/04 ISOmodem integrates the DAA, analog
features, such as parallel phone detect, overcurrent
detection, and global PTT compliance with a single
design, are included.
4.1. Host Interface
The Si2457/34/15/04 interfaces to the host processor
through either an asynchronous serial interface, a
synchronous Serial Peripheral Interface (SPI), or a
parallel interface. The default is asynchronous serial
communication. Selection of either SPI or parallel
interface is done on power-up with reset strapping.
Please refer to “AN93: ISOmodem® Chipset Family
Designer's Guide” for details.
4.1.1. Asynchronous Serial Interface
The Si2457/34/15/04 supports asynchronous serial
communication with data terminal equipment (DTE) at
rates up to 307.2 kbps with the standard serial UART
format. Upon powerup, the UART baud rate is
automatically detected using the autobaud feature.
4.1.2. Serial Peripheral Interface (SPI)
The serial peripheral interface (SPI) provides a flexible,
full-duplex synchronous serial bus for host processor
and Si2457/34/15/04 ISOmodem communication. When
the Si2457/34/15/04 is powered up with SPI mode
enabled the modem becomes an SPI slave, and the
pins are configured to SS (slave select input, active
low), MOSI (serial data input to modem), MISO (serial
data output from modem) and SCLK (serial data clock
input). Each SPI operation consists of a control-andaddress byte and a data byte.
4.1.3. Parallel Interface (24-Pin Version Only)
The Si2457/34/15/04 can also communicate via a
parallel interface when using the 24-pin version. The
parallel interface is an 8-bit data bus with a single bit
address to memory mapped registers.
Rev. 1.3
17
Si2457/34/15/04
4.2. Command Mode
4.7. Low-Power Modes
Upon reset, the ISOmodem® is in command mode and
accepts “AT” commands. An outgoing modem call can
be made using the “ATDT#” (tone dial) or “ATDP#”
(pulse dial) command after the device is configured. If
the handshake is successful, the modem responds with
the response codes detailed in Table 12 on page 38 and
enters data mode.
The Si2457/34/15/04 provides multiple low power
modes. Using the S24 S-register, the Si2457/34/15/04
can be set to automatically enter sleep mode after a
pre-programmed time of inactivity with either the DTE or
the remote modem. The sleep mode is entered after
(S24) seconds have passed since the last DTE activity,
after the transmit FIFO is empty, and after the last data
are received from the remote modem.
4.3. Data Mode
The Si2457/34/15/04 ISOmodem is in data mode while
it has a telephone line connection to another modem or
is in the process of establishing a connection.
Data protocols are available to provide error correction
to improve reliability (V.42 and MNP2-4) and data
compression to increase throughput (V.44, V.42bis and
MNP5).
Each connection between two modems in data mode
begins with a handshaking sequence. During this
sequence, the modems determine the line speed, data
protocol, and related parameters for the data link.
Configuration through AT commands determines the
range of choices available to the modem during the
negotiation process.
4.4. Fast Connect
The Si2457/34/15/04 supports a fast connect mode of
operation to reduce the time of a connect sequence in
originate mode. The Fast Connect modes can be
enabled for V.21, V.22, Bell103, and V.29 modulations.
See AN93 for details.
4.5. V.80 Synchronous Access Mode
The Si2457/34/15/04 supports a V.80 synchronous
access mode of operation, which operates with an
asynchronous DTE and a synchronous DCE. See
“AN93: ISOmodem® Chipset Family Designer's Guide”.
4.6. Clocking
The Si2457/34/15/04 contains an on-chip phase-locked
loop (PLL) and clock generator to derive all necessary
internal system clocks from a single clock input. A
32.768 kHz or 4.9152 MHz crystal can be used across
XTALI and XTALO pins to form the master clock
(±100 ppm max, ±25 ppm recommended) for the
ISOmodem. The 32.768 kHz option can provide lower
BOM costs and smaller footprint. Alternatively, a clock
input of 27 MHz, 4.9152 MHz, or 32.768 kHz can be
provided to XTALI if that clock source is available in the
system. A 4.9152 MHz clock input is the default clock
option. Other clock options are selected at power-up
through reset strapping. Refer to AN93 for details.
18
Additionally, the Si2457/34/15/04 can be placed in
wake-on-ring-mode using the command, AT&Z. In either
mode, the ISOmodem remains in the sleep state until
one of the following occurs:
A 1-to-0 transition on TXD (UART mode).
 A 1-to-0 transition on SS (SPI mode).
 A 1-to-0 transition on CS (parallel mode).
 An incoming ring is detected.
 A parallel telephone is picked up.
 Line polarity reversal
The Si2457/34/15/04 may also be placed in a complete
powerdown mode. Once the Si2457/34/15/04
completely powers down, it can only be powered back
on via the RESET pin.

4.8. Data Compression
The modem can achieve DTE (host-to-ISOmodem)
speeds greater than the maximum DCE (modem-tomodem) speed through the use of a data compression
protocol. The compression protocols available are the
ITU-T V.42bis and MNP5 protocols. Data compression
attempts to increase throughput by compressing the
data before actually sending it. Thus, the modem is able
to transmit more data in a given period of time.
4.9. Error Correction
The Si2457/34/15/04 ISOmodem can employ error
correction (reliable) protocols to ensure error-free
delivery of asynchronous data sent between the host
and the remote end. The Si2457/34/15/04 supports V.42
and MNP2-4 error correction protocols. V.42 (LAPM) is
most commonly used and is enabled by default.
4.10. Wire Mode
Wire mode is used to communicate with standard nonerror correcting modems. When optioned with \N3, the
Si2457/34/15/04 falls back to wire mode if it fails in an
attempt to negotiate a V.42 link with the remote modem.
Error correction and data compression are not active in
wire mode.
Rev. 1.3
Si2457/34/15/04
4.11. Caller ID Operation
The Si2457/34/15/04 supports full type I and type II
caller ID detection and decode. Caller ID is supported
for the US Bellcore, European ETSI, UK, and Japanese
protocols and is enabled via the +VCID, +VCDT, and
+PCW commands.
4.12. Parallel Phone Detection
The ISOmodem® is able to detect when another
telephone, modem, or other device is using the phone
line. This allows the host to avoid interrupting another
phone call when the phone line is already in use and to
intelligently handle an interruption when the ISOmodem
is using the phone line.
4.12.1. On-Hook Line-in-use Detection
When the ISOmodem is sharing the telephone line with
other devices, it is important that it not interrupt a call in
progress. To detect whether another device is using the
shared telephone line, the host can use the ISOmodem
to monitor the TIP-RING dc voltage with the line voltage
sense (LVS) register (U6C, bits 15:8).
The LVS bits have a resolution of 1 V per bit with an
accuracy of approximately ±10%. Bits 0 through 6 of
this 8-bit signed twos complement number indicate the
value of the line voltage, and the sign bit (bit 7) indicates
the polarity of TIP and RING. The ISOmodem can also
monitor the TIP-RING dc voltage using the LVCS
register (U79, bits 4:0). See Figure 9 on page 19. See
also the %Vn commands for automatic line-in-use
detection.
4.12.2. Off-Hook Intrusion Detection
When the ISOmodem is off-hook, an algorithm is
implemented in the ISOmodem to automatically monitor
the TIP-RING loop current via the LVCS register. During
the off-hook state, the LVCS register switches from
representing the TIP-RING voltage to representing the
TIP-RING current. See Figure 10 on page 20. Upon
detecting an intrusion, the ISOmodem alerts the host of
the condition via the INT pin.
30
25
20
LVC S
BITS
15
10
5
0
0 3 6
9 12 15 18 21 24 28 30 33 36 39 42 45 47 51 54 57 60 63 66 69 72 75 78 81 84 87
100
Loop Voltage (V)
Figure 9. Loop Voltage
Rev. 1.3
19
Si2457/34/15/04
Overload
30
25
20
CTR21 only
LVCS
BITS
15
10
5
0
0 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60 63 66 69 72 75 78 81 84 87 90 93
Loop Current
(mA)
Figure 10. Loop Current
20
Rev. 1.3
140
Si2457/34/15/04
4.13. Overcurrent Detection
4.17. SMS/MMS Support
The Si2457/34/15/04 includes an overcurrent detection
feature that measures the loop current at a
programmable time after the Si2457/34/15/04 goes offhook. This allows the Si2457/34/15/04 to detect if it is
connected to an improper telephone line. The
overcurrent detection feature may be enabled by setting
the OCDM bit (U70, bit 11). OHT (U77, bits 8:0) sets the
delay after off-hook until the loop current is measured.
See “AN93: ISOmodem® Chipset Family Designer's
Guide” for details.
Additionally, the user-access registers (via the AT:U and
AT:R commands) may be programmed for countryspecific settings, such as dial tone, ring, ringback, and
busy tone. See AN93 for complete details.
Short Message Service (SMS) is a service that allows
text messages to be sent and received from one
telephone to another via an SMS service center.
Multimedia Messaging Service (MMS) extends the core
SMS capability to send messages that include
multimedia content. The Fax ISOmodem provides an
interface that offers a great deal of flexibility in handling
multiple SMS standards. This flexibility is possible
because most of the differences between standards are
handled by the host using the raw data itself. The
Si2457/34/15/04 performs the necessary modulation/
demodulation of the data and provides two options for
message packet structure (Protocol 1 and Protocol 2, as
defined in ETSI ES 201 912). The rest of the data link
layer and transfer layer are defined by the host system.
The content of the message is entirely up to the host
including any checksum or CRC. ETSI ES 201 912
describes two standard data and transfer layers that are
commonly used. SMS typically relies on caller
identification information to determine if the call should
be answered using an SMS device or not.
See “6.4. SMS Support” in AN93 for more information
on how to configure the modem for SMS support.
4.15. Firmware Upgrades
4.18. Codec Interface (24-Pin Version Only)
The Si2457/34/15/04 contains an on-chip program ROM
that includes the firmware required for the features
listed in this data sheet. In addition, the Si2457/34/15/04
contains on-chip program RAM to accommodate minor
changes to the ROM firmware. This allows Silicon Labs
to provide future firmware updates to optimize the
characteristics of new modem designs and those
already deployed in the field. See AN93 for complete
details.
In order to support a full range of voice and data
applications, the Si2457/34/15/04 includes an optional
serial interface that connects to an external voice codec
(Si3000). See AN93 for complete details.
4.14. Global Operation
The Si2457/34/15/04 chipset contains an integrated
silicon direct access arrangement (Silicon DAA) that
provides a programmable line interface to meet
international telephone line interface requirements.
“AN93: Modem Designer’s Guide” gives the DAA
register settings required to meet international PTT
standards.
4.16. DTMF Detection / Generation
The Si2457/34/15/04 provides comprehensive DTMF
tone generation and detection. The ISOmodem can
generate single tones or DTMF tones using the +VTS
command. DTMF tones may also be generated during
dialing using the “ATDT” command. DTMF detection is
only available in voice mode (+FCLASS = 8). DTMF
digits are reported from the modem to the host using
<DLE> shielding.
4.19. EEPROM Interface
(24-Pin Version Only)
The Si2457/34/15/04 supports an optional serial
peripheral interface (SPI) bus serial EEPROM Mode 3
with a 16-bit (8–64 kbit range) address. Upon powerup,
if a pulldown resistor 10 k is placed between D6 and
GND, the ISOmodem attempts to detect an EEPROM.
The EEPROM is intended first for setting custom
defaults, second for automatically loading firmware
upgrades, and third to allow for user-defined AT
command macros for use in custom AT commands or
country codes. See AN93 for complete details.
4.20. AT Commands
At powerup, the Si2457/34/15/04 is in the AT command
mode. In command mode, the modem monitors the
input (serial or parallel) checking constantly for a valid
command (AT commands are described in Table 8.)
Rev. 1.3
21
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold)
Command
Action
$
Display AT command mode settings.
A
Answer incoming call
A/
Dn
Re-execute last command. This is the only command not preceded by “AT” or followed by a
<CR>.
Dial
The dial command, followed by 1 or more dial command modifiers, manually dials a phone
number:
Modifier
Function
! or &
Flash hook switch for FHT (U4F) ms (default: 500 ms)
Pause before continuing for S8 seconds (default:
, or <
2 seconds)
;
Return to AT command mode
@
Wait for silence.
Polarity reversal detect. By placing the “G” character in
the dial string (i.e. ATDTG1), the Si2457/34/15/04 will
monitor the telephone line for polarity reversals. If a
busy tone is detected, the Si2457/34/15/04 will report
“POLARITY REVERSAL” if a polarity reversal was
detected or “NO POLARITY REVERSAL” if a polarity
reversal was not detected. In each case, the result
G
code is followed by “OK”. If the S7 timeout occurs
before a busy tone is detected, the Si2457/34/15/04 will
report “NO CARRIER”. Polarity reversal monitoring
begins after the last digit is dialed and ends when the
busy tone is detected or S7 timeout occurs.
Note: It is not possible to establish a modem connection
when using this command.
L
P
T
W
22
En
Local DTE echo
E0
Disable
E1
Enable
Hn
Hook switch.
Redial last number.
Pulse (rotary) dialing—pulse digits: 0, 1, 2, 3, 4, 5, 6, 7,
8, 9
Tone (DTMF) dialing—DTMF digits: *, #, A, B, C, D, 0,
1, 2, 3, 4, 5, 6, 7, 8, 9.
Wait for dial tone before continuing for S14 seconds
(default: 12 seconds). Blind dialing modes X0, X1 and
X3 do not affect the W command.
If the DOP bit (U7A, bit 7) is set, the “ATDTW” command will cause the ISOmodem® to pause dialing and
either report an “OK” if a dialtone is detected or “NO
DIALTONE” if a dial tone is not detected.
Rev. 1.3
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
Action
H0
Go on-hook (hang up modem).
H1
Go off-hook.
In
Identification and checksum.
I0
I1
Display Si2457/34/15/04 revision code.
B: Revision B
C: Revision C, etc.
Display Si2457/34/15/04 firmware revision code (numeric).
I7
Display line-side revision code.
18C = Si3018 revision C
Display the ISOmodem® model number.
“2404” = Si2404
“2415” = Si2415
“2434” = Si2434
“2457” = Si2457
Diagnostic results 1. See “AN93: ISOModem® Chipset Family Designer’s Guide” for details.
I8
Diagnostic results 2. See AN93 for details.
Ln
Speaker volume operation
L1
Low speaker volume
L2
Medium speaker volume
L3
High speaker volume
Mn
Speaker operation (via AOUT).
M0
Speaker is always off.
M1
Speaker is on while dialing and handshaking; off in data mode.
M2
Speaker is always on.
M3
Speaker is off while dialing, on during handshaking and retraining.
On
Return to data mode from Command mode operation.
O0
Return to data mode.
O1
Return to data mode and perform a full retrain (at any speed except 300 bps).
O2
Return to data mode and perform rate renegotiation.
Qn
Response mode.
Q0
Enable result codes (see Table 12 on page 38)
Q1
Disable result codes (enable quiet mode).
I3
I6
R
Initiate V.23 reversal.
Sn
S-register operation (see Table 13 on page 41).
S$
List contents of all S registers.
Sn?
Display contents of S-register n.
Rev. 1.3
23
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
Sn=x
Set S-register n to value x (where n and x are decimal values).
Vn
Result code type (see Table 12 on page 38).
V0
Numeric result codes.
V1
Verbal result codes
Xn
X0
X1
Call Progress Monitor (CPM)—This command controls which CPM signals are monitored
and reported to the host from the Si2457/34/15/04. (See Table 12 on page 38.)
Basic results; disable CPM—Blind dial (does not wait for dial tone). CONNECT message
does not include speed.
Extended results; disable CPM—Blind dial. CONNECT message includes speed.
X3
Extended results and detect dial tone only—Add dial tone detection to X1 mode. Does not
blind dial.
Extended results and detect busy only—Add busy tone detection to X1 mode.
X4
Extended results, full CPM—Full CPM enabled, CONNECT message includes speed.
X2
Y0
Extended results—Full CPM enabled including ringback detection. Adds ringback detection
to X4 mode.
Long space disconnect—Modem hangs up after 1.5 seconds or more of continuous space
while on-line.
Disable.
Y1
Enable.
X5
Yn
Z
:E
:I
:M
:P
:R
24
Action
Hard Reset—This command is functionally equivalent to pulsing the RESET pin low. (See
tAT in Table 6 on page 7.)
Read from serial EEPROM.
Interrupt Read—This command causes the ISOmodem® to report the lower 8 bits of the
interrupt register I/O Control 0 (U70). The CID, OCD, PPD, and RI bits also are cleared, and
the INT pin (INT bit in parallel mode) is deactivated on this read.
Write to serial EEPROM.
Program RAM Write—This command is used to upload firmware supplied by Silicon Labs to
the Si2457/34/15/04. The format for this command is AT:Paaaa,xxxx,yyyy,.... where aaaa is
the first address in hexadecimal and xxxx,yyyy,.... is data in hexadecimal. Only one :P command is allowed per AT command line. No other commands can be concatenated in the :P
command line. This command is only for use with special files provided by Silicon Laboratories. Do not attempt to use this command for any other purpose.
User-Access Register Read—This command allows the user to read from the user-access
registers (see "6. User-Access Registers (U-Registers)" on page 44). The format is “AT:Raa”,
where:
aa = user-access address in hexadecimal.
The “AT:R” command causes all the U- registers to be displayed.
Rev. 1.3
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
:U
+DR=X
+DS Options
+DS = A
+DS = A,B
+DS = A,B,C
+DS = A,B,C,D
Action
User-Access Register Write—This command allows the user to write to the 16-bit useraccess registers. (See page page 44.) The format is “AT:Uaa,xxxx,yyyy,zzzz,...” where
aa = user-access address in hexadecimal.
xxxx = Data in hexadecimal to be written to location aa.
yyyy = Data in hexadecimal to be written to location (aa + 1).
zzzz = Data in hexadecimal to be written to location (aa + 2).
etc.
Data compression reporting.
X
Mode
0
Disabled
1
Enabled
If enabled, the intermediate result code is transmitted at the point after error control negotiation. The format of this result code is as follows:
Result code
Mode
+DR:NONE
Data compression is not in use
+DR:V42B
Rec. V.42bis is in use in both directions
+DR:V42B RD Rec. V.42bis is in use in receive direction only
+DR:V42B TD Rec. V.42bis is in use in transmit directions only
Controls V.42bis data compression function.
A
Direction
0 No compression
1 Transmit only
2 Receive only
3 Both Directions
B
Compression_negotiation
0 Do not disconnect if V.42 is not negotiated.
1 Disconnect is V.42 is not negotiated.
C
Maximum dictionary size
512
D
+ES Options
+ES = A
+ES = A,,C
Maximum string size
6 to 250 (28 default)
Enable synchronous access mode.
A
Specifies the mode of operation when initiating a modem connection.
D Disable synchronous assess mode.
6 Enable synchronous access mode when connection is completed and data state is
entered.
B
Specifies fallback mode of operation.
This parameter should not be used.
C
Specifies the mode of operation when answer a modem connection.
D Disable synchronous assess mode.
8 Enable synchronous access mode when connection is completed and data state is
entered.
Rev. 1.3
25
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
Action
Synchronous access mode control options
A
Specifies action taken if an underrun condition occurs during transparent sub-mode.
0 Modem transmits 8-bit SYN sequences on idle.
B
Specifies action taken if an underrun condition occurs after a flag during framed submode
0 Modem transmits 8-bit HDLC flags on idle.
C
Specifies action taken if an underrun or overrun condition occurs after a non-flag during
+ESA Options
framed sub-mode.
+ESA = A
0
Modem transmits abort on underrun in middle of frame.
+ESA = A,B
1 Modem transmits flag on underrun in middle of frame and notifies host of underrun
+ESA = A,B,C
or overrun.
+ESA = A,B,C,E
Specifies V.34 half duplex operation.
+ESA = A,B,C,E,F D
This parameter should not be used.
+ESA = A,B,C,E,F,
E
Specifies
CRC polynomial used while in framed sub-mode.
G
0 CRC generation checking disable.
1 16-bit CRC generation and checking is performed by the modem.
F
Specifies NRZI encoding and decoding.
0 NRZI encoding and decoding disabled.
G
Specifies SYN.
255
Class 1 Mode Enable for V.29 fast connect.
X
Mode
+FCLASS = X
0
Off
1
Enables support for Class 1 mode for use in the V.29 fast connect mode.
Class 1 Receive Carrier for V.29 fast connect.
X
Mode
2
Transmit V.21 (980 Hz) tone for longer than 100 ms, then send answer tone
+FRM = X
(2100/2225 Hz) for 200 ms.
95
V.29 short synchronous.
96
V.29 full synchronous.
Class 1 Transmit Carrier for V.29 fast connect.
X
Mode
2
Transmit V.21 (980 Hz) tone.
53
Same as &T4, but transmit V.29 7200 bps. Data pattern set by S40 register. AT +
FCLASS = 0 must be sent to restore the ISOmodem® to normal operation after
+FTM = X
test.
54
Same as &T4, but transmit V.29 9600 bps. Data pattern set by S40 register. AT +
FCLASS = 0 must be sent to restore the ISOmodem to normal operation after test.
95
V.29 short synchronous.
96
V.29 full synchronous.
26
Rev. 1.3
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
+GCI = X
Action
Country settings - Automatically configure all registers for a particular country.
X
Country
0
Japan
9
Australia
A
Austria
F
Belgium
16
Brazil
1B
Bulgaria
20
Canada
26
China
27
Columbia
2E
Czech Republic
31
Denmark
35
Ecuador
3C
Finland
3D
France
42
Germany
46
Greece
50
Hong Kong
51
Hungary
53
India
57
Ireland
58
Israel
59
Italy
61
South Korea
69
Luxembourg
6C
Malaysia
73
Mexico
7B
Netherlands
7E
New Zealand
82
Norway
87
Paraguay
89
Philippines
8A
Poland
8B
Portugal
9C
Singapore
9F
South Africa
A0
Spain
A5
Sweden
A6
Switzerland
B8
Russia
B4
United Kingdom
B5
United States
FE
Taiwan
Note: U-registers are configured to Silicon Laboratories’ recommended values. The +GCI command
resets the U-registers and the S7 and S6 S-registers to default values before setting countryspecific values. Changes may be made by writing individual registers after sending the AT+GCI
command. Refer to “AN93: ISOModem® Chipset Family Designer’s Guide” for details.
+GCI?
+GCI = ?
List current country code setting (response is: + GCI:<setting>)
List all possible country code settings.
Rev. 1.3
27
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
Action
Specifies the flow control to be implemented.
A
Specifies the flow control method used by the host to control data from the modem
0 None
1 Local XON/OFF flow control. Does not pass XON/XOFF character to the remote
+IFC Options
modem.
+IFC = A
2 Hardware flow control (RTS)
+IFC = A,B
B
Specifies the flow control method used by the modem to control data from the host
0 None
1 Local XON/OFF flow control.
2 Hardware flow control (CTS).
Transmit flow control threshold.
A
Threshold above which the modem will generate a flow off signal
+ITF Options
<0 to 511> bytes
+ITF = A
B
Threshold below which the modem will generate a flow on signal
+ITF = A,B
<0 to 511> bytes
+ITF = A,B,C
C
Polling interval for <EM><BNUM> indicator
0 to 300 in 10 msec units.
Modulation reporting control.
X
Mode
0
Disabled
1
Enabled
+MR = X
If enabled, the intermediate result code is transmitted at the point during connect negotiation.
The format of this result code is as follows:
+MCR: <carrier> e.g. +MCR: V32B
+MRR: <rate>
e.g. +MRR: 14400
Modulation Selection.
A
Preferred modem carrier
V21
ITU-T V.21
V22
ITU-T V.22
V22B ITU-T V.22bis (default for Si2404)
V32
ITU-T V.32
+MS Options
V32B
ITU-T V.32bis (default for Si2415)
+MS = A
V34
ITU-T
V.34 (default for Si2434)
+MS = A,B
V90
ITU-T
V.90 (default for Si2457)
+MS = A,B,C
B
Automatic modulation negotiation
+MS = A,B,C,D
0
Disabled
+MS = A,B,C,D,E
1
Enabled
+MS = A,B,C,D,E,F
C,D
Min TX rate/Max TX rate are optional numeric values that specify the lowest value
at which the DCE may establish a connection. If unspecified (set to 0), they are
determined by the carrier and automode settings.
E,F
Min RX rate/Max RX rate are optional numeric values which specify the highest
value at which the DCE may establish a connection. If unspecified (set to 0), they
are determined by the carrier and automode settings.
28
Rev. 1.3
Si2457/34/15/04
Table 8. Basic AT Command Set (Command Defaults in Bold) (Continued)
Command
+PCW = X
+VCDT = X
+VCID = X
+VCIDR?
Action
Controls the action to be taken upon detection of call waiting.
Mode
X
0
Toggle RI and collect type II Caller ID if enabled by +VCID.
1
Hang up.
2
Ignore call waiting.
Caller ID Type.
Mode
X
0
After ring only
1
Always on (Recommended Setting)
2
UK
3
Japan
Caller ID Enable.
X
Mode
0
Off
1
On—formatted
2
On—raw data format
Type II caller ID information — The Si2457/34/15/04 will display “+VCDIR:” followed by raw
caller ID information including checksum.
Rev. 1.3
29
Si2457/34/15/04
4.21. Extended AT Commands
The extended AT commands are supported by the Si2457/34/15/04 and are described in Tables 9 through 11.
Table 9. Extended AT& Command Set (Command Defaults in Bold)
Command
Action
&$
Display AT& current settings.
&D0
ESC is not used
&D1
ESC escapes to command mode from data mode if also enabled by HES U70, bit 15.
&D2
ESC assertion during a modem connection causes the modem to go on-hook and return to command mode.
&D3
ESC assertion causes ATZ command (reset and return OK result code).
&F
Restore factory default settings.
&Gn
Line connection rate limit—This command sets an upper limit on the line speed that the Si2457/34/
15/04 can connect. Note that the &Hn commands may limit the line speed as well (&Gn not used for
&H0 or &H1). Not all modulations support rates given by &G. Any improper setting will be ignored.
&G3
1200 bps max
&G4
2400 bps max (default for Si2404)
&G5
4.8 kbps max
&G6
7.2 kbps max
&G7
9.6 kbps max
&G8
12 kbps max
&G9
14.4 kbps max (default for Si2415)
&G10
16.8 kbps max
&G11
19.2 kbps max
&G12
21.6 kbps max
&G13
24 kbps max
&G14
26.4 kbps max
&G15
28.8 kbps max
&G16
31.2 kbps max
&G17
33.6 kbps max (default for Si2457 and Si2434)
&Hn
Switched network handshake mode—&Hn commands must be on a separate command line from
ATD, ATA, or ATO commands.
&H0
V.90 with automatic fallback (56 kbps to 300 bps) (default for Si2457)
&H1
V.90 only (56 kbps to 28 kbps)
&H2
V.34 with automatic fallback (33.6 kbps to 300 bps) (default for Si2434)
&H3
V.34 only (33.6 kbps to 2400 bps)
30
Rev. 1.3
Si2457/34/15/04
Table 9. Extended AT& Command Set (Command Defaults in Bold) (Continued)
Command
Action
&H4
ITU-T V.32bis with automatic fallback (14.4 kbps to 300 bps) (default for Si2415)
&H5
ITU-T V.32bis only (14.4 kbps to 4800 bps)
&H6
ITU-T V.22bis only (2400 bps or 1200 bps)
&H7
ITU-T V.22 only (1200 bps)
&H8
Bell 212 only (1200 bps)
&H9
Bell 103 only (300 bps)
&H10
ITU-T V.21 only (300 bps)
&H11
V.23 (1200/75 bps)
&Pn
Japan pulse dialing
&P0
Configure Si2457/34/15/04 for 10 pulse-per-second pulse dialing. For Japan.
&P1
Configure Si2457/34/15/04 for 20 pulse-per-second pulse dialing. For Japan.
&Tn
Test mode
&T0
Cancel test mode (Escape to command mode to issue AT&T0). This command will also report the
number of bit errors encountered on the previous &T4 or &T5 test.
&T2
Initiate ITU-T V.54 (ANALOOP) test. Modulation set by &H AT command. Test loop is through the
DSP (Si2457/34/15/04 device) only. ISOmodem® echoes data from TX pin (Register 0 in parallel
mode) back to RX pin (Register 0 in parallel mode).
&T3
Initiate ITU-T V.54 (ANALOOP) test. Modulation set by &H AT command. Test loop is through the
DSP (Si2457/34/15/04), DAA interface section (Si2457/34/15/04), DAA interface (Si3018), and analog hybrid circuit (Si3018). ISOmodem echoes data from TX pin (Register 0 in parallel mode) back to
RX pin (Register 0 in parallel mode). Phone line termination required as in Figure 1. To test only the
link operation, the hybrid and AFE codec can be removed from the test loop by setting the DL bit
(U62, bit 1).
&T4
Initiate transmit as originating modem with automatic data generation. Modulation, data rate, and
symbol rate are set by &H, &G, and S41. Data pattern is set by the S40 register. Continues until the
ATH command is sent after an escape into command mode. Data is also demodulated as in
ANALOOP, and any bit errors are counted to be displayed after the test using &T0.
&T5
Initiate transmit as answering modem with automatic data generation. Modulation, data rate, and
symbol rate are set by &H, &G, and S41. Data pattern is set by the S40 register. Continues until the
ATH command is sent after an escape into command mode. Data is also demodulated as in
ANALOOP, and any bit errors are counted to be displayed after the test using &T0.
&T6
Compute checksum for firmware-upgradeable section of program memory. If no firmware upgrade is
installed, &T6 returns 0x4474.
&Xn
Automatic determination of telephone line type.
&X0
Abort &x1 or &x2 command.
Rev. 1.3
31
Si2457/34/15/04
Table 9. Extended AT& Command Set (Command Defaults in Bold) (Continued)
Command
&X1
Action
Automatic determination of telephone line type.
Result code: WXYZn
W:
0 = line supports DTMF dialing.
1 = line is pulse dial only.
X:
0 = line supports 20 pps dialing.
1 = line supports 10 pps dialing only.
Y:
0 = extension network present (PBX).
1 = outside line (PSTN) connected directly.
Z:
0 = continuous dialtone.
1 = make-break dialtone.
n:
0–9 (number required for outside line if Y = 0).
Note: The initial number attempted for an outside line is controlled in S51.
&X2
Same as &X1, but Y result (PBX) is not tested.
*Y2A
Produce a constant answer tone (ITU-T) and return to command mode. The answer tone continues
until the ATH command is received or the S7 timer expires.
&Z
Enter low-power wake-on-ring mode.
32
Rev. 1.3
Si2457/34/15/04
Table 10. Extended AT% Command Set (Command Defaults in Bold)
Command
Action
%$
Display AT% command settings.
%B
Report blacklist. See also S42 register.
%Cn
Data compression
%C0
Disable V.42bis and MNP5 data compression
%C1
Enable V.42bis in transmit and receive paths. If MNP is selected (\N2), then %C1 enables
MNP5 in transmit and receive paths.
%C2
Enable V.42bis in transmit path only.
%C3
Enable V.42bis in receive path only.
%On
Answer mode.
%O1
Si2457/34/15/04 will auto-answer a call in answer mode.
%O2
Si2457/34/15/04 will auto-answer a call in originate mode.
%Vn
Automatic Line Status Detection.
After the %V1 and %V2 commands are issued, the Si2457/34/15/04 will automatically check the
telephone connection for whether or not a line is present. If a line is present, the Si2457/34/15/04
will automatically check if the line is already in use. Finally, the Si2457/34/15/04 will check line status
both before going off-hook and again before dialing. %V1 uses the fixed method, and %V2 uses the
adaptive method. %V0 (default) disables this feature.
%V0
Disable automatic line-in-use detection.
%V1
Automatic Line Status Detection—Fixed Method.
Description: Before going off-hook with the ATD, ATO, or ATA commands, the Si2457/34/15/04 compares the line voltage (via LVCS) to registers NOLN (U83) and LIUS (U84):
Loop Voltage
0  LVCS  NOLN
NOLN  LVCS  LIUS
LIUS  LCVS
Action
Report “NO LINE” and remain on-hook.
Report “LINE IN USE” and remain on-hook.
Go off-hook and establish a modem connection.
Once the call has begun, the off-hook intrusion algorithm (described in "4.12.2. Off-Hook Intrusion
Detection" on page 19) operates normally. In addition, the Si2457/34/15/04 will report “NO LINE” if
the telephone line is completely disconnected. If the HOI bit (U77, bit 11) is set, “LINE IN USE” is
reported upon intrusion.
Rev. 1.3
33
Si2457/34/15/04
Table 10. Extended AT% Command Set (Command Defaults in Bold) (Continued)
Command
Action
%V2
Automatic Line Status Detection—Adaptive Method.
Description: Before going off-hook with the ATD, ATO, or ATA commands, the Si2457/34/15/04 compares the line voltage (via LVCS) to the NLIU (U85) register:
Loop Voltage
Action
0  LVCS  (0.0625 x NLIU)
Report “NO LINE” and remain on-hook.
(0.0625 x NLIU) < LVCS  (0.85 x NLIU) Report “LINE IN USE” and remain on-hook.
(0.85 x NLIU) < LCVS
Go off-hook and establish a modem connection.
The NLIU register is updated every 1 ms with the minimum non-zero value of LVCS in the last
30 ms. This allows the Si2457/34/15/04 to eliminate errors due to 50/60 Hz interference and also
adapt to relatively slow change in the on-hook dc reference value on the telephone line. This algorithm does not allow any non-zero values for NLIU below 0x0007. The host may also initialize NLIU
prior to issuing the %V2 command. Once the call has begun, the off-hook intrusion algorithm
(described in "4.12.2. Off-Hook Intrusion Detection" on page 19) operates normally. In addition, the
Si2457/34/15/04 will report “NO LINE” if the telephone line is completely disconnected. If the HOI
(U77, bit 11) bit is set, “LINE IN USE” is reported upon intrusion.
34
Rev. 1.3
Si2457/34/15/04
Table 11. Extended AT\ Command Set (Command Defaults in Bold)
Command
\$
Action
Display AT\ command settings.
\Bn
Character length will be automatically set in autobaud mode
\B0
6N1—six data bits, no parity, one stop bit, one start bit, eight bits total (\N0 only)1
\B1
7N1—seven data bits, no parity, one stop bit, one start bit, nine bits total (\N0 only)1
\B2
7P1—seven data bits, parity optioned by \P, one stop bit, one start bit, 10 bits total
\B3
8N1—eight data bits, no parity, one stop bit, one start bit, 10 bits total
\B5
8P1—eight data bits, parity optioned by \P, one stop bit, one start bit, 11 bits total (\N0 only)
\B6
8X1—eight data bits, one escape bit, one stop bit, one start bit, 11 bits total (enables ninth-bit
escape mode)
\Nn
Asynchronous protocol
\N0
Wire mode (no error correction, no compression)
\N2
MNP reliable mode. The Si2457/34/15/04 attempts to connect with the MNP protocol. If unsuccessful, the call is dropped.
\N3
V.42 auto-reliable—The Si2457/34/15/04 attempts to connect with the V.42 protocol. If unsuccessful, the MNP protocol is attempted. If unsuccessful, wire mode is attempted.
\N4
V.42 (LAPM) reliable mode (or drop call)—Same as \N3 except that the Si2457/34/15/04 drops the
call instead of connecting in MNP or wire mode.
\N5
V.42 and MNP reliable mode—The Si2457/34/15/04 attempts to connect with V.42. If unsuccessful,
MNP is attempted. If MNP us unsuccessful, the call is dropped.
\Pn
Parity type will be automatically set in autobaud mode
\P0
Even
\P1
Space1
\P2
Odd
\P3
Mark1
\Qn
Modem-to-DTE flow control
\Q0
Disable all flow control—This may only be used if the DTE speed and the VF speed are guaranteed
to match throughout the call.
\Q2
Use CTS only
Notes:
1. When in autobaud mode, \B0, \B1, and \P1 will not be detected automatically. The combination of \B2 and \P3 will be
detected. This is compatible with seven data bits, no parity, two stop bits. Seven data bits, no parity, one stop bit may be
forced by sending AT\T17\B1.
2. The autobaud feature does not detect this rate.
3. Default is \T9 if a pulldown resistor is connected to the autobaud strap pin; otherwise, the default is \T16.
Rev. 1.3
35
Si2457/34/15/04
Table 11. Extended AT\ Command Set (Command Defaults in Bold) (Continued)
Command
Action
\Q3
Use RTS/CTS
\Q4
Use XON/XOFF flow control for modem-to-DTE interface. Does not enable modem-to-modem flow
control.
\Tn
DTE rate—Change DTE rate. When the Si2457/34/15/04 is configured in autobaud mode (default),
\T0 through \T15 will lock the new baud rate and disable autobaud. When the ISOmodem® is not in
autobaud mode (the autobaud strap pin low on powerup), the result code “OK” is sent at the old DTE
rate. Subsequent commands must be sent at the new rate.
\T0
300 bps
\T1
600 bps
\T2
1200 bps
\T3
2400 bps
\T4
4800 bps
\T5
7200 bps
\T6
9600 bps
\T7
12.0 kbps2
\T8
14.4 kbps
\T9
19.2 kbps3
\T10
38.4 kbps
\T11
57.6 kbps
\T12
115.2 kbps
\T13
230.4 kbps
\T14
245.760 kbps2
\T15
307.200 kbps
\T16
Autobaud on3
\T17
Autobaud off; lock at current baud rate.
Notes:
1. When in autobaud mode, \B0, \B1, and \P1 will not be detected automatically. The combination of \B2 and \P3 will be
detected. This is compatible with seven data bits, no parity, two stop bits. Seven data bits, no parity, one stop bit may be
forced by sending AT\T17\B1.
2. The autobaud feature does not detect this rate.
3. Default is \T9 if a pulldown resistor is connected to the autobaud strap pin; otherwise, the default is \T16.
36
Rev. 1.3
Si2457/34/15/04
Table 11. Extended AT\ Command Set (Command Defaults in Bold) (Continued)
Command
Action
\U
Serial mode—causes a low pulse (25 ms) on RI and DCD. INT to be the inverse of ESC. RTS to be
inverse of CTS.
Parallel mode—causes a low pulse (25 ms) on INT.
This command terminates with a RESET.
\Vn
Connect message type
\V0
Report connect message and protocol message
\V2
Report connect message only (exclude protocol message)
\V4
Report connect and protocol message with both upstream and downstream connect rates.
Notes:
1. When in autobaud mode, \B0, \B1, and \P1 will not be detected automatically. The combination of \B2 and \P3 will be
detected. This is compatible with seven data bits, no parity, two stop bits. Seven data bits, no parity, one stop bit may be
forced by sending AT\T17\B1.
2. The autobaud feature does not detect this rate.
3. Default is \T9 if a pulldown resistor is connected to the autobaud strap pin; otherwise, the default is \T16.
Rev. 1.3
37
Si2457/34/15/04
Table 12. Result Codes
Numeric
Meaning
Verbal Response
X0
X1
X2
X3
X4
X5
0
Command was successful
OK
X
X
X
X
X
X
1
Link established at 300 bps
or higher
CONNECT
X
X
X
X
X
X
2
Incoming ring detected
RING
X
X
X
X
X
X
3
Link dropped
NO CARRIER
X
X
X
X
X
X
4
Command failed
ERROR
X
X
X
X
X
X
5
Link establish at 1200
CONNECT 1200
X
X
X
X
X
6
Dial tone not present
NO DIALTONE
X
X
7
Line busy
BUSY
X
X
X
8
Remote not answering
NO ANSWER
X
9
Ringback detected
RINGING
10
Link established at 2400
CONNECT 2400
11
12
Link established at 4800
Link established at 9600
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
CONNECT 12000
1
X
X
X
X
X
CONNECT 14400
1
X
X
X
X
X
2
X
CONNECT 4800
1
CONNECT 9600
1
14
Link established at 19200
CONNECT 19200
15
Link established at 7200
CONNECT 72001
16
17
Link established at 12000
Link established at 14400
1
18
Link established at 16800
CONNECT 16800
X
X
X
X
X
19
Link established at 21600
CONNECT 216002
X
X
X
X
X
Link established at 24000
CONNECT 24000
2
X
X
X
X
X
CONNECT 26400
2
X
X
X
X
X
2
20
21
Link established at 26400
22
Link established at 28800
CONNECT 28800
X
X
X
X
X
23
Link established at 31200
CONNECT 312002
X
X
X
X
X
24
Link established at 33600
CONNECT 33600
2
X
X
X
X
X
30
Caller ID mark detected
CIDM
X
X
X
X
X
X
31
Hookswitch flash detected
FLASH
X
X
X
X
X
X
32
UK CID State Tone Alert
Signal detected
STAS
X
X
X
X
X
X
33
Overcurrent condition
X2
X
X
X
X
X
X
40
Blacklist is full
BLACKLIST FULL (enabled
via S42 register)
X
X
X
X
X
X
41
Attempted number is blacklisted.
BLACKLISTED (enabled via
S42 register)
X
X
X
X
X
X
42
No phone line present
NO LINE (enabled via %Vn
commands)
X
X
X
X
X
X
Notes:
1. This message is only supported on the Si2457, Si2434, and Si2415.
2. This message is only supported on the Si2457 and Si2434.
3. X is the only verbal response code that does not follow the <CR><LF>Result Code<CR><LF> standard. There is no
leading <CR><LF>.
4. This message is only supported on the Si2457.
38
Rev. 1.3
Si2457/34/15/04
Table 12. Result Codes (Continued)
Numeric
Meaning
Verbal Response
X0
X1
X2
X3
X4
X5
43
Telephone line is in use
LINE IN USE (enabled via
%Vn commands)
X
X
X
X
X
X
44
A polarity reversal was
detected
POLARITY REVERSAL
(enabled via G modifier)
X
X
X
X
X
X
45
A polarity reversal was NOT NO POLARITY REVERSAL
detected
(enabled via G modifier)
X
X
X
X
X
X
52
Link established at 56000
CONNECT 560004
X
X
X
X
X
Link established at 32000
CONNECT 32000
4
X
X
X
X
X
CONNECT 48000
4
X
X
X
X
X
4
60
61
Link established at 48000
63
Link established at 28000
CONNECT 28000
X
X
X
X
X
64
Link established at 29333
CONNECT 293334
X
X
X
X
X
Link established at 30666
CONNECT 30666
4
X
X
X
X
X
CONNECT 33333
4
X
X
X
X
X
4
65
66
Link established at 33333
67
Link established at 34666
CONNECT 34666
X
X
X
X
X
68
Link established at 36000
CONNECT 360004
X
X
X
X
X
69
Link established at 37333
CONNECT 37333
4
X
X
X
X
X
70
No protocol
PROTOCOL: NONE
75
Link established at 75
CONNECT 75
X
77
V.42 protocol
PROTOCOL: V42
Set with \V0 command.
79
V.42bis protocol
PROTOCOL: V42bis
Set with \V0 command.
80
MNP2 protocol
PROTOCOL:
ALTERNATE, + CLASS 2
Set with \V command.
81
MNP3 protocol
PROTOCOL:
ALTERNATE, + CLASS 3
Set with \V command.
82
MNP4 protocol
PROTOCOL:
ALTERNATE, + CLASS 4
Set with \V command.
83
MNP5 protocol
PROTOCOL:
ALTERNATE, + CLASS 5
X
X
X
X
X
90
Link established at 38666
CONNECT 386664
X
X
X
X
X
91
Link established at 40000
CONNECT
400004
X
X
X
X
X
92
Link established at 41333
CONNECT 413334
X
X
X
X
X
Link established at 42666
CONNECT
426664
X
X
X
X
X
CONNECT
440004
X
X
X
X
X
453334
93
94
Link established at 44000
Set with \V0 command.
X
X
X
X
95
Link established at 45333
CONNECT
X
X
X
X
X
96
Link established at 46666
CONNECT 466664
X
X
X
X
X
Link established at 49333
CONNECT
493334
X
X
X
X
X
CONNECT
506664
X
X
X
X
X
97
98
Link established at 50666
Notes:
1. This message is only supported on the Si2457, Si2434, and Si2415.
2. This message is only supported on the Si2457 and Si2434.
3. X is the only verbal response code that does not follow the <CR><LF>Result Code<CR><LF> standard. There is no
leading <CR><LF>.
4. This message is only supported on the Si2457.
Rev. 1.3
39
Si2457/34/15/04
Table 12. Result Codes (Continued)
Numeric
99
100
Meaning
Link established at 52000
Link established at 53333
Verbal Response
X1
X2
X3
X4
X5
CONNECT 52000
4
X
X
X
X
X
CONNECT 53333
3
X
X
X
X
X
3
X
X
X
X
X
X
X
X
X
X
101
Link established at 54666
CONNECT 54666
102
DTMF dial attempted on a
pulse dial only line
UN–OBTAINABLE NUMBER
X0
X
Notes:
1. This message is only supported on the Si2457, Si2434, and Si2415.
2. This message is only supported on the Si2457 and Si2434.
3. X is the only verbal response code that does not follow the <CR><LF>Result Code<CR><LF> standard. There is no
leading <CR><LF>.
4. This message is only supported on the Si2457.
40
Rev. 1.3
Si2457/34/15/04
5. S-Registers
The S command allows reading (Sn?) or writing (Sn = x) the S-registers. The S-registers store values for functions
that typically are rarely changed, such as timers or counters, and the ASCII values of control characters, such as
carriage return. Table 13 summarizes the S-register set.
Table 13. S-Register Description
Definition
S-Register
(Decimal)
Function
Default
(Decimal)
Range
Units
0
Automatic answer—Number of rings the Si2457/34/15/
04 must detect before answering a call. 0 disables auto
answer.
0
0–255
Rings
1
Ring counter.
0
0–255
Rings
2
ESC code character.
43 (+)
0–255
ASCII
3
Carriage return character.
13 (CR)
0–255
ASCII
4
Linefeed character.
10 (LF)
0–255
ASCII
5
Backspace character.
08 (BS)
0–255
ASCII
6
Dial tone wait timer—Number of seconds the Si2457/
34/15/04 waits before blind dialing. Only applicable if
blind dialing is enabled (X0, X1, X3).
02
0–255
seconds
7
Carrier wait timer—Number of seconds the Si2457/34/
15/04 waits for carrier before timing out. This register
also sets the number of seconds the modem waits for
ringback when originating a call before hanging up.
This register also sets the number of seconds the
answer tone will continue while using the AT Y2A
command.
80
0–255
seconds
8
Dial pause timer for , and < dial command modifiers.
02
0–255
seconds
9
Carrier presence timer—Time after a loss of carrier
that a carrier must be detected before reactivating
DCD. S9 is referred to as “carrier loss debounce time.”
06
1–255
0.1 second
10
Carrier loss timer—Time the carrier must be lost before
the Si2457/34/15/04 disconnects. Setting 255 disables
disconnect entirely. If S10 is less than S9, even a
momentary loss of carrier causes a disconnect.
14
1–255
0.1 second
12
Escape code guard timer—Minimum guard time
required before and after “+++” for the Si2457/34/15/
04 to recognize a valid escape sequence.
50
1–255
0.02 second
14
Wait for dial tone delay value (in relation to the W dial
modifier). Starts when “W” is executed in the dial
string.
12
0–255
seconds
*
Rev. 1.3
41
Si2457/34/15/04
Table 13. S-Register Description (Continued)
Definition
S-Register
(Decimal)
Function
Default
(Decimal)
Range
Units
24
Sleep Inactivity Time—Sets the time that the modem
operates in normal power mode with no activity on the
serial port, parallel port, or telephone line before entering low-power sleep mode. This feature is disabled if
the timer is set to 0.
0
0–255
seconds
30
Disconnect Activity Timer—Sets the length of time that
the modem stays online before disconnecting with no
activity on the serial port, parallel port, or telephone
line (Ring, hookswitch flash, or caller ID). This feature
is disabled if set to 0.
0
0–255
minutes
38
Hang Up Delay Time—Maximum delay between
receipt of ATH0 command and hang up. If time out
occurs before all data can be sent, the NO CARRIER
(3) result code is sent (operates in V.42 mode only).
“OK” response is sent if all data is transmitted before
timeout. S38 = 255 disables timeout and modem disconnects only if data is successfully sent or carrier is
lost.
20
0–255
seconds
40
Data Pattern—Data pattern generated during &T4 and
&T5 transmit tests.
0 = All spaces (0s)
1 = All marks (1s)
2 = Random data
0
0–2
41
V.34 symbol rate - Symbol rate for V.34 when using the
&T4 and &T5 commands.
0 = 2400
symbols/second
1 = 2743
symbols/second
2 = 2800
symbols/second
3 = 3000
symbols/second
4 = 3200
symbols/second
5 = 3429
symbols/second
A valid combination of symbol rate (S41) and data rate
(&G) must be selected.
Symbol Rate Allowable Data Rates
2400
2400–21600
2743
4800–26400
2800
4800–26400
3000
4800–28800
3200
4800–31200
3429
4800–33600
0
0–5
42
Rev. 1.3
Si2457/34/15/04
Table 13. S-Register Description (Continued)
Definition
S-Register
(Decimal)
Function
Default
(Decimal)
Range
42
Blacklisting—The Si2457/34/15/04 will not dial the
same number more than two times in three minutes.
An attempt to dial a third time within three minutes will
result in a “BLACKLISTED” result code. If the blacklist
memory is full, any dial to a new number will result in a
“BLACKLIST FULL” result code. Numbers are added
to the blacklist only if the modem connection fails. The
%B command will list the numbers on the blacklists.
0 = disabled
1 = enabled
0 (disabled)
0–1
43
Dial Attempts to Blacklist.
When blacklisting is enabled with S42, this value controls the number of dial attempts that will result in a
number being blacklisted.
4
0–4
44
Blacklist Timer.
Period during which blacklisting is active.
180
0–255
seconds
50
Minimum on-hook time—Modem will remain on-hook
for S50 seconds. Any attempt to go off-hook will be
delayed until this timer expires.
3
0–255
seconds
51
Number to start checking for an outside line on a PBX.
See &X command for details.
1
0–9
Rev. 1.3
Units
43
Si2457/34/15/04
6. User-Access Registers
(U-Registers)
U-Registers are 16-bit registers written by the AT:Uaa
command and read by the AT:R (read all U-Registers)
or AT:Raa (read U-Register aa) commands (see the AT
command list in Table 11 on page 35). Many aspects of
the modem’s and DAA’s behavior can be enabled/
disabled, configured, monitored, and/or modified
through U-Registers; however, most of them will not be
needed in normal use.
There are two types of U-Registers. The first represents
a single 16-bit term, such as a filter coefficient,
threshold, delay, or other quantity. These registers can
be read from or written to as a single 16-bit value. The
second type of U-Register is bit-mapped. Bit-mapped
registers are written and/or read in hexadecimal, but
each bit or combination of bits in the register represents
an independent value or status information. These
individual bits are used to enable or disable features
and indicate states.
Some U-Registers are reserved and not available to the
user. Therefore, there are gaps in the available URegister address map. Additionally, some bits within
available U-Registers are reserved. Any attempt to write
a non-zero value to a reserved U-Register or bit may
cause unpredictable modem operation.
With over 100 U-Registers, the Si2457/34/15/04 offers
an unprecedented level of programmability for a
controller-based modem. A detailed list of these
registers and their use is beyond the scope of this data
sheet. Refer to “AN93: ISOmodem® Chipset Family
Designer’s Guide” for details.
44
Rev. 1.3
Si2457/34/15/04
7. Pin Descriptions: Si2457/34/15/04 (16-Pin Option)
Si2457/34/15/04
(16-Pin Option)
Pin #
1
CLKIN/XTALI
1
16
SS/RTS
XTALO
RI
VD
2
15
DCD
3
4
14
13
MISO/RXD
MOSI/TXD
SCLK/CTS
RESET
5
6
7
12
11
ESC
VA
GND
INT
10
9
C1A
C2A
8
Pin Name
Description
CLKIN/XTALI XTALI—Crystal Oscillator Pin.
Provides support for parallel resonant AT cut crystals. A 4.9152 MHz or 32.768 kHz crystal
or a 32.768 kHz or 4.9152 or 27 MHz clock on XTALI is required.
2
XTALO
3
RI
Ring Indicator.
The RI on (active low) indicates the presence of an ON segment of a ring signal on the telephone line.
4
VD
Supply Voltage.
Provides the 3.3 V supply voltage to the Si2457/34/15/04.
5
MISO/RXD
Master In Slave Out/Receive Data.
Serial data output from modem in SPI mode.
Data output to DTE RXD pin in UART mode.
6
MOSI/TXD
Master Out Slave In/Transmit Data.
Serial data input to modem in SPI mode.
Data input from DTE TXD pin in UART mode.
7
SCLK/CTS
Serial Data Clock/Clear to Send.
Signals that the Si2457/34/15/04 is ready to receive more digital data on the TXD pin.
Serial data clock input in SPI mode.
8
RESET
9
C2A
Isolation Capacitor 2A.
Connects to one side of the isolation capacitor C2.
10
C1A
Isolation Capacitor 1A.
Connects to one side of the isolation capacitor C1.
11
INT
Interrupt Output.
Active low interrupt output.
XTALO—Crystal Oscillator Pin.
Serves as the output of the crystal amplifier.
Reset Input.
An active low input that is used to reset all control registers to a defined, initialized
state.
Rev. 1.3
45
Si2457/34/15/04
Pin #
Pin Name
12
GND
13
VA
14
ESC
Escape.
A positive edge on this pin causes the modem to go from online (connected) mode to
the offline (command) mode.
15
DCD
Carrier Detect.
Active low carrier detect.
16
SS/RTS
46
Description
Ground.
Connects to the system digital ground.
Regulator Voltage Reference.
Connects to an external capacitor and serves as the reference for the internal
voltage regulator.
SPI Slave Select/Request to Send.
Active low slave select in SPI mode.
Active low request to send input used for flow control in UART mode.
Rev. 1.3
Si2457/34/15/04
8. Pin Descriptions: Si2457/34/15/04 (24-Pin Option)
Si2457/34/15/04
(24-Pin Option)
CLKIN/XTALI
1
24
SDO/EECLK/D5
XTALO
23
CLKOUT/EECS/A0
2
3
DCD/D4
ESC/D3
FSYNC/D6
4
21
VD3.3
5
GND
6
20
19
VDA
7
18
SDI/EESD/D2
SS/RTS/D7
8
RI/D1
INT/DO
AOUT/INT
22
VD3.3
GND
VDB
MOSI/TXD/WR
9
10
17
16
15
SCLK/CTS/CS
11
14
C1A
RESET
12
13
C2A
MISO/RXD/RD
Pin #
Pin Name
Description
1
CLKIN/XTALI
2
XTALO
3
CLKOUT/EECS/
A0
Clock Output/EEPROM Chip Select/Address Bit 0.
Clock output in serial mode. Active low read/write enable for SPI EEPROM in
serial mode when pin 4 is pulled low during powerup. Address Enable in parallel
mode.
4
FSYNC/D6
Frame Sync/Data Bit.
Frame Sync output to codec in serial mode. Bidirectional parallel bus data bit 6 in
parallel mode.
5, 21
VD3.3
Digital Supply Voltage.
Provides the 3.3 V supply voltage to the Si2457/34/15/04.
6, 20
GND
Ground.
Connects to the system digital ground.
7,19
VDA, VDB
Clock Input/Crystal Oscillator Pin.
Provides support for parallel resonant AT cut crystals. A 4.9152 MHz or
32.768 kHz crystal or a 32.768 kHz or 4.9152 or 27 MHz clock on XTALI is
required.
Crystal Oscillator Pin.
Serves as the output of the crystal amplifier.
Regulator Voltage Reference.
Connects to an external capacitor and serves as the reference for the internal
voltage regulator.
8
SS/RTS/D7
SPI Slave Select/Request to Send/Data Bit.
Active low slave select in SPI mode.
Active low request to send input used for flow control in UART mode. Bidirectional parallel bus data bit 7 in parallel mode.
Rev. 1.3
47
Si2457/34/15/04
48
Pin #
Pin Name
Description
9
MISO/RXD/RD
Master In Slave Out/Receive Data/Read Enable.
Serial data output from modem in SPI mode. Data output to DTE RXD pin in
UART mode. Active low read enable pin in parallel mode.
10
MOSI/TXD/WR
Master Out Slave In/Transmit Data/Write Enable.
Serial data input to modem in SPI mode. Data input from DTE TXD pin in serial
mode. Active low write enable pin in parallel mode.
11
SCLK/CTS/CS
Serial Data Clock/Clear to Send/Chip Select.
Serial data clock input in SPI mode. Signals that the Si2457/34/15/04 is ready to
receive more digital data on the TXD pin in data mode. Active low chip select in
parallel mode.
12
RESET
Reset Input.
An active low input that is used to reset all control registers to a defined initialized
state.
13
C2A
Isolation Capacitor 2A.
Connects to one side of the isolation capacitor, C2.
14
C1A
Isolation Capacitor 1A.
Connects to one side of the isolation capacitor, C1.
15
AOUT/INT
16
INT/D0
Interrupt Output/Data Bit.
Active low interrupt output in serial mode. Bidirectional parallel bus data bit 0 in
parallel mode.
17
RI/D1
Ring Indicator/Data Bit.
The RI on (active low) indicates the presence of an ON segment of a ring signal
on the telephone line. Bidirectional parallel bus data bit 1 in parallel mode.
18
SDI/EESD/D2
Serial Data In/EEPROM Serial Data Input/Output/Data Bit.
Serial Data In (to codec) output in serial mode. Bidirectional Input/Output to SPI
EEPROM in serial mode when pin 4 is pulled low during power up. Bidirectional
parallel bus data bit 2 in parallel mode.
22
ESC/D3
Escape/Data Bit.
Hardware escape in serial mode. Bidirectional parallel bus data bit 3 in parallel
mode.
23
DCD/D4
Carrier Detect/Data Bit.
Active low carrier detect in serial mode. Bidirectional parallel bus data bit 4 in parallel mode.
24
SDO/EECLK/D5
Serial Data Out/EEPROM Clock/Data Bit 5.
Serial Data Out (from codec) input in serial mode. Clock output for SPI EEPROM
in serial mode when pin 4 is pulled low during power up. Bidirectional parallel bus
data bit 5 in parallel mode.
Analog Output/Interrupt Output.
Analog output in serial mode. Active low interrupt output in parallel mode.
Rev. 1.3
Si2457/34/15/04
9. Pin Descriptions: Si3018/10
Si3018/10
QE
1
DCT
2
3
4
RX
IB
C1B
C2B
VREG
5
6
7
RNG1
8
16
15
DCT2
14
13
DCT3
QB
QE2
IGND
12
11
SC
10
9
VREG2
RNG2
Table 14. Si3018/10 Pin Descriptions
Pin #
1
Pin Name
QE
2
DCT
3
RX
4
IB
5
C1B
6
C2B
7
VREG
8
RNG1
9
RNG2
10
VREG2
11
SC
12
QE2
13
QB
14
DCT3
15
IGND
16
DCT2
Description
Transistor Emitter.
Connects to the emitter of Q3.
DC Termination.
Provides dc termination to the telephone network.
Receive Input.
Serves as the receive side input from the telephone network.
Internal Bias.
Provides a bias voltage to the device.
Isolation Capacitor 1B.
Connects to one side of isolation capacitor C1 and communicates with the system side.
Isolation Capacitor 2B.
Connects to one side of isolation capacitor C2 and communicates with the system side.
Voltage Regulator.
Connects to an external capacitor to provide bypassing for an internal power supply.
Ring 1.
Connects through a resistor to the RING lead of the telephone line. Provides the ring and
caller ID signals to the Si2457/34/15/04.
Ring 2.
Connects through a resistor to the TIP lead of the telephone line. Provides the ring and
caller ID signals to the Si2457/34/15/04.
Voltage Regulator 2.
Connects to an external capacitor to provide bypassing for an internal power supply.
SC Connection.
Enables external transistor network. Should be tied through a 0  resistor to IGND.
Transistor Emitter 2.
Connects to the emitter of Q4.
Transistor Base.
Connects to the base of transistor Q4.
DC Termination 3.
Provides the dc termination to the telephone network.
Isolated Ground.
Connects to ground on the line-side interface.
DC Termination 2.
Provides dc termination to the telephone network.
Rev. 1.3
49
Si2457/34/15/04
10. Ordering Guide
Chipset
Max Speed
System-Side
Package
System-Side*
Line-Side*
Temp Range
Si2457
56 kbps
24-pin TSSOP
Si2457-D-FT
Si3018-F-FS
0 to 70 °C
Si2457
56 kbps
16-pin SOIC
Si2457-D-FS
Si3018-F-FS
0 to 70 °C
Si2434
33.6 kbps
24-pin TSSOP
Si2434-D-FT
Si3018-F-FS
0 to 70 °C
Si2434
33.6 kbps
16-pin SOIC
Si2434-D-FS
Si3018-F-FS
0 to 70 °C
Si2415
14.4 kbps
24-pin TSSOP
Si2415-D-FT
Si3018-F-FS
0 to 70 °C
Si2415
14.4 kbps
16-pin SOIC
Si2415-D-FS
Si3018-F-FS
0 to 70 °C
Si2404
2400 bps
24-pin TSSOP
Si2404-D-FT
Si3010-F-FS
0 to 70 °C
Si2404
2400 bps
16-pin SOIC
Si2404-D-FS
Si3010-F-FS
0 to 70 °C
Si2457
56 kbps
24-pin TSSOP
Si2457-D-GT
Si3018-F-GS
–40 to +85 °C
Si2434
33.6 kbps
24-pin TSSOP
Si2434-D-GT
Si3018-F-GS
–40 to +85 °C
Si2415
14.4 kbps
24-pin TSSOP
Si2415-D-GT
Si3018-F-GS
–40 to +85 °C
Si2404
2400 bps
24-pin TSSOP
Si2404-D-GT
Si3018-F-GS
–40 to +85 °C
*Note: Add an “R” at the end of the device to denote tape and reel option.
50
Rev. 1.3
Si2457/34/15/04
11. Package Markings (Top Markings)
Codes for the Si2457-D-FT, Si2457-D-FS, Si2434-D-FT, Si2434-D-FS, Si2415-D-FT, Si2415-D-FS, Si2404-D-FT,
Si2404-D-FS, Si3018-F-FS, and Si3010-F-FS top marks are as follows:
YY = Current Year
WW = Work Week
 R = Die Revision
 TTTTT = Trace Code
 XX = Assembly Country Code


11.1. Si2457-D-FT Top Marking
Figure 11. Si2457-D-FT Top Marking
11.2. Si2457-D-FS Top Marking
Figure 12. Si2457-D-FS Top Marking
11.3. Si2434-D-FT Top Marking
Figure 13. Si2434-D-FT Top Marking
Rev. 1.3
51
Si2457/34/15/04
11.4. Si2434-D-FS Top Marking
Figure 14. Si2434-D-FS Top Marking
11.5. Si2415-D-FT Top Marking
Figure 15. Si2415-D-FT Top Marking
11.6. Si2415-D-FS Top Marking
Figure 16. Si2415-D-FS Top Marking
11.7. Si2404-D-FT Top Marking
Figure 17. Si2404-D-FT Top Marking
52
Rev. 1.3
Si2457/34/15/04
11.8. Si2404-D-FS Top Marking
Figure 18. Si2404-D-FS Top Marking
11.9. Si3010-F-FS Top Marking
Figure 19. Si3010-F-FS Top Marking
11.10. Si3018-F-FS Top Marking
Figure 20. Si3018-F-FS Top Marking
Rev. 1.3
53
Si2457/34/15/04
12. Package Outline: 24-Pin TSSOP
Figure 21 illustrates the package details for the Si2457/34/15/04 24-pin packaging option. Table 15 lists the values
for the dimensions shown in the illustration.
Figure 21. 24-Pin Thin Shrink Small Outline Package (TSSOP)
Table 15. Package Diagram Dimensions
Dimension
Min
Nom
Max
A
—
—
1.20
A1
0.05
—
0.15
A2
0.80
1.00
1.05
b
0.19
—
0.30
c
0.09
—
0.20
D
7.70
7.80
7.90
E
E1
6.40 BSC
4.30
4.40
e
L
0.45
0.60
L2
θ
4.50
0.65 BSC
0.75
0.25 BSC
0°
—
aaa
0.10
bbb
0.10
ccc
0.20
8°
Notes:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
3. This drawing conforms to the JEDEC Solid State Outline MO-153,
Variation AD.
4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020
specification for Small Body Components.
54
Rev. 1.3
Si2457/34/15/04
13. 24-Pin TSSOP Land Pattern
Figure 22 illustrates the recommended land pattern for the Si2457/34/15/04 24-Pin TSSOP. Table 16 lists the
values for the dimensions shown in the illustration.
Figure 22. 24-Pin TSSOP Land Pattern Diagram
Table 16. 24-Pin TSSOP PCB Land Pattern
Dimension
Feature
(mm)
C1
Pad Column Spacing
5.80
E
Pad Row Pitch
0.65
X1
Pad Width
0.45
Y1
Pad Length
1.40
Notes:
1. This Land Pattern Design is based on IPC-7351 specifications for Density Level B
(Median Land Protrusion).
2. All feature sizes shown are at Maximum Material Condition (MMC) and a card
fabrication tolerance of 0.05 mm is assumed.
Rev. 1.3
55
Si2457/34/15/04
14. Package Outline: 16-Pin SOIC
Figure 23 illustrates the package details for the Si2457/34/15/04 16-pin packaging option. Table 17 lists the values
for the dimensions shown in the illustration.
Figure 23. 16-Pin Small Outline Integrated Circuit (SOIC) Package
56
Rev. 1.3
Si2457/34/15/04
Table 17. Package Diagram Dimensions
Dimension
Min
Max
A
—
1.75
A1
0.10
0.25
A2
1.25
—
b
0.31
0.51
c
0.17
0.25
D
9.90 BSC
E
6.00 BSC
E1
3.90 BSC
e
1.27 BSC
L
0.40
L2
1.27
0.25 BSC
h
0.25
0.50
θ
0°
8°
aaa
0.10
bbb
0.20
ccc
0.10
ddd
0.25
Notes:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
3. This drawing conforms to the JEDEC Solid State Outline MS-012,
Variation AC.
4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020
specification for Small Body Components.
Rev. 1.3
57
Si2457/34/15/04
15. 16-Pin SOIC Land Pattern
Figure 24 illustrates the recommended land pattern for the Si2457/34/15/04 16-Pin SOIC. Table 18 lists the values
for the dimensions shown in the illustration.
Figure 24. 16-Pin SOIC Land Pattern Diagram
Table 18. 16-Pin SOIC Land Pattern Dimensions
Dimension
Feature
(mm)
C1
Pad Column Spacing
5.40
E
Pad Row Pitch
1.27
X1
Pad Width
0.60
Y1
Pad Length
1.55
Notes:
General
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ASME Y14.5M-1994.
3. This Land Pattern Design is based on the IPC-7351 guidelines.
4. All dimensions shown are at Maximum Material Condition (MMC). Least Material
Condition (LMC) is calculated based on a Fabrication Allowance of 0.05 mm.
Solder Mask Design
5. All metal pads are to be non-solder mask defined (NSMD). Clearance between the
solder mask and the metal pad is to be 60 µm minimum, all the way around the pad.
Stencil Design
6. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls should
be used to assure good solder paste release.
7. The stencil thickness should be 0.125 mm (5 mils).
8. The ratio of stencil aperture to land pad size should be 1:1.
Card Assembly
9. A No-Clean, Type-3 solder paste is recommended.
10. The recommended card reflow profile is per the JEDEC/IPC J-STD-020
specification for Small Body Components.
58
Rev. 1.3
Si2457/34/15/04
DOCUMENT CHANGE LIST
Revision 0.91 to Revision 1.0








Added Figure 5 typical schematic with 16-pin
system-side option.
Updated Table 3 to include 16-pin system-side
parameters.
Updated default register setting in Table 16.
Added Si2404 information.
Added 16-pin system-side option.
Updated "4. Functional Description" on page 17.
Added "7. Pin Descriptions: Si2457/34/15/04 (16-Pin
Option)" on page 45.
Updated "10. Ordering Guide" on page 50 to reflect
part revision.
Revision 1.0 to Revision 1.1

Added industrial temperature range devices.
Revision 1.1 to Revision 1.2

Added Revision D additions and changes:
32.768
SPI


kHz oscillator option
interface
Moved U-Register details to AN93.
Added package markings.
Revision 1.2 to Revision 1.3
Removed 5 V interface logic support.
 Lowered digital input voltage VIND max from 5.3 V to
(VD + 0.3) V.

Lowered total supply current (typ) from 26 to 17 mA.
 Added total supply current, wake-on-ring
specification.

Rev. 1.3
59
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Connected.
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