Si2456/33/14
V. 9 0 , V. 3 4 , V. 3 2 B I S I SO M O D E M ® C H I PS E T
WITH
I N T E G R A T E D G L O B A L DAA
Features
Data modem formats
Integrated DAA
ITU-T, Bell
300 bps up to 56 kbps
V.42, V.42bis, MNP2-5
Automatic rate negotiation
Over 5000 V capacitive isolation
Parallel phone detect
Globally-compliant line interface
Caller ID decode
3.3 V power
No external ROM or RAM required
UART with flow control
AT command set support
Overcurrent detection
Fast connect
Parallel interface
Call progress support
Firmware upgradeable
Applications
Set-top boxes
E-mail terminals
Point-of-sale terminals
Digital video recorders
Security systems
Remote monitoring
Ordering Information
This data sheet is valid only for
those chipset combinations listed
on page 69.
Pin Assignments
Description
Si2456/33/14
The Si2456 is a complete, ITU-V.90-compliant, 56 kbps modem chipset
with integrated direct access arrangement (DAA) that provides a
programmable line interface to meet global telephone line requirements
with a single design. Available in two small packages, it eliminates the
need for a separate DSP data pump, external RAM and ROM, modem
controller, codec, isolation transformer, relays, opto-isolators, and 2- to 4wire hybrid. The ISOmodem® chipset is ideal for embedded modem
applications due to its small board space, low power consumption, and
global compliance. The Si2433 and Si2414 products offer all the same
features as the Si2456 with connect rates of up to 33.6 kbps and
14.4 kbps, respectively.
CLKIN/XTALI
1
24
XTALO
2
23
DCD/D4
CLKOUT/EECS/A0
3
22
ESC/D3
EECLK/D5
D6
4
21
C1A
VD3.3
5
ISOB
GND
6
20
19
VDA
7
18
GND
RTS/D7
8
17
VDB
RXD/RD
9
16
EESD/D2
TXD/WR
10
15
RI/D1
CTS/CS
11
14
INT/D0
RESET
12
13
AOUT/INT
VD3.3
Functional Block Diagram
Si3015
CLKIN/XTALI
RXD
TXD
CTS
RTS
DCD
ESC
RI
PLL
Clocking
RAM/ROM
RNG1
RNG2
Data Bus
QB
QE
Serial
Interface
C1A
Microcontroller
DSP
INT
CS
WR
RD
A0
D0-D7
IGND
C1B
DAA
Interface
Si3015
CLKOUT
QE2
DCT
XTALO
4
5
6
7
8
16
15
FILT2
FILT
14
13
RX
REXT
12
11
REF
10
9
VREG2
VREG
REXT2
To Phone
Line
AOUT
Parallel
Interface
1
2
3
Patents pending
ISOB
RESET
Rev. 1.2 8/06
Copyright © 2006 by Silicon Laboratories
Si2456/33/14
Si2456/33/14
2
Rev. 1.2
Si2456/33/14
TA B L E O F C O N T E N TS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3. Bill of Materials: Si2456/33/14 Chipset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1. Digital Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.2. Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.3. Parallel Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
4.4. Command Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
4.5. Data Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.6. Fast Connect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
4.7. V.29 Fast Connect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.8. Clocking/Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.9. Data Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.10. Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.11. Wire Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
4.12. Caller ID Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
4.13. Parallel Phone Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.14. Overcurrent Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.15. Global Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.16. Firmware Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
4.17. EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.18. AT Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
4.19. Extended AT Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5. S-Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
6. User-Access Registers (U-Registers) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.1. Bit-Mapped U-Register Detail (defaults in bold) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
7. Parallel Interface Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
8. Pin Descriptions: Si2456/33/14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
9. Pin Descriptions: Si3015 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
10. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
11. Package Outline: 24-Pin TSSOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
12. Package Outline: 16-Pin SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
Rev. 1.2
3
Si2456/33/14
1. Electrical Specifications
Table 1. Recommended Operating Conditions
Symbol
Test Condition
Min2
Typ
Max2
Unit
Ambient Temperature
TA
K-Grade, F-Grade
0
25
70
°C
Ambient Temperature
TA
B-Grade
–40
25
85
°C
Si2456/33/14 Supply Voltage, Digital3
VD
3.0
3.3
3.6
V
Parameter1
Notes:
1. The Si2456/33/14 specifications are guaranteed when the typical application circuit (including component tolerance)
and any Si2456/33/14 and any Si3015 are used. See "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. The Si2456/33/14 interface supports 5 V logic (CLKIN/XTALI
supports 3.3 V logic only).
4
Rev. 1.2
Si2456/33/14
Table 2. DAA Loop Characteristics
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for K-Grade)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
DC Termination Voltage
VTR
IL = 20 mA, ACT1 = 1
DCT = 11 (CTR21)
—
—
7.5
V
DC Termination Voltage
VTR
IL = 42 mA, ACT = 1
DCT = 11 (CTR21)
—
—
14.5
V
DC Termination Voltage
VTR
IL = 50 mA, ACT = 1
DCT = 11 (CTR21)
—
—
40
V
DC Termination Voltage
VTR
IL = 60 mA, ACT = 1
DCT = 11 (CTR21)
40
—
—
V
DC Termination Voltage
VTR
IL = 20 mA, ACT = 0
DCT = 01 (Japan)
—
—
6.0
V
DC Termination Voltage
VTR
IL = 100 mA, ACT = 0
DCT = 01 (Japan)
9
—
—
V
DC Termination Voltage
VTR
IL = 20 mA, ACT = 0
DCT = 10 (FCC)
—
—
7.5
V
DC Termination Voltage
VTR
IL = 100 mA, ACT = 0
DCT = 10 (FCC)
9
—
—
V
On-Hook Leakage Current
ILK
VTR = –48 V
—
—
7
μA
Operating Loop Current
ILP
FCC/Japan Modes
13
—
120
mA
Operating Loop Current
ILP
CTR21
13
—
60
mA
DC flowing through
ring detection circuitry
—
—
7
µA
DC Ring Current2
Ring Detect Voltage3
VRD
RT = 0
11
—
22
Vrms
3
VRD
RT = 1
17
—
33
Vrms
FR
15
—
68
Hz
REN
—
—
0.2
Ring Detect Voltage
Ring Frequency
Ringer Equivalence Number4
Notes:
1. ACT = U67, bit 5; DCT = U67, bits 3:2; RT = U67, bit 0; RZ = U67, bit 1.
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. C15, R14, Z2, and Z3 not installed. RZ = 0.
Rev. 1.2
5
Si2456/33/14
TIP
+
600 Ω
Si3015
IL
VTR
10 µF
–
RING
Figure 1. Test Circuit for Loop Characteristics
Table 3. DC Characteristics, VD = 3.3 V
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for K-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
IL
–10
—
10
µA
RPU
50
100
200
kΩ
Input Leakage Current
Pullup Resistance Pins 3,4,9,11,
13,14,16,23,24
Total Supply Current*
Total Supply Current, Powerdown
*
ID
VD33 pin
—
26
35
mA
ID
PDN = 1
—
80
—
μA
*Note: All inputs at 0 or VD. All inputs held static except clock, and all outputs unloaded (Static IOUT = 0 mA).
6
Rev. 1.2
Si2456/33/14
Table 4. DAA AC Characteristics
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for K-Grade)
Parameter
Symbol
Sample Rate
Crystal Oscillator Frequency
Test Condition
Min
Typ
Max
Unit
Fs
—
9.6
—
kHz
FXTL
—
4.9152
—
MHz
Transmit Frequency Response
Low –3 dBFS Corner
—
5
—
Hz
Receive Frequency Response
Low –3 dBFS Corner
—
5
—
Hz
—
1
—
VPEAK
Transmit Full Scale Level
1
1
Receive Full Scale Level
VFS
—
1
—
VPEAK
DR
ACT5
DCT5
= 0,
= 10 (FCC)
IL=100 mA
—
82
—
dB
Dynamic Range2,3,6
DR
ACT = 0, DCT = 01 (Japan)
IL = 20 mA
—
83
—
dB
Dynamic Range2,3,4
DR
ACT = 1, DCT = 11(CTR21)
IL = 60 mA
—
84
—
dB
Transmit Total Harmonic
Distortion4,7
THD
ACT = 0, DCT = 10 (FCC)
IL = 100 mA
—
–85
—
dB
Transmit Total Harmonic
Distortion5,7
THD
ACT = 0, DCT = 01 (Japan)
IL = 20 mA
—
–76
—
dB
Receive Total Harmonic
Distortion6,7
THD
ACT = 0, DCT = 01 (Japan)
IL = 20 mA
—
–74
—
dB
Receive Total Harmonic
Distortion4,7
THD
ACT = 1, DCT = 11 (CTR21)
IL = 60 mA
—
–82
—
dB
AOUT Dynamic Range
VIN = 1 kHz
—
40
—
dB
AOUT THD
VIN = 1 kHz
—
40
—
dB
AOUT Full-Scale Level
—
0.7VDD
—
VPP
AOUT Mute Level
—
60
—
dB
Dynamic
Range2,3,4
VFS
Notes:
1. Measured at TIP and RING with 600 Ω termination at 1 kHz.
2. DR = 20 x log |Vin| + 20 x log (RMS signal/RMS noise).
3. Measurement is 300 to 3400 Hz. Applies to transmit and receive paths.
4. Vin = 1 kHz, –3 dBFS, Fs = 10300 Hz.
5. ACT = U67, bit 5; DCT = U67, bits 3:2.
6. Vin = 1 kHz, –6 dBFS, Fs = 10300 Hz.
7. THD = 20 x log (RMS distortion/RMS signal).
Rev. 1.2
7
Si2456/33/14
Table 5. Absolute Maximum Ratings
Parameter
Symbol
Value
Unit
DC Supply Voltage
VD
4.1
V
Input Current, Si2456/33/14 Digital Input Pins
IIN
±10
µA
Digital Input Voltage
VIND
–0.3 to 5.3
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 Characteristics
(VD = 3.0 to 3.6 V, TA = 0 to 70 °C for K-Grade)
Parameter
Symbol
CLKOUT Output Clock Frequency
Min
Typ
Max
Unit
2.4576
—
39.3216
MHz
Baud Rate Accuracy
tBD
–1
—
1
%
CTS or RTS ↑ High to Start Bit↓
tRTS
10
—
—
ns
RESET ↓ to RESET ↑
tRS
5.0
—
—
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
Read Cycle Time
tRC
120
—
—
ns
Write Data Setup Time
RD Low Pulse Width
RD Low to Data Driven Time
Note: All timing is referenced to the 50% level of the waveform. Input test levels are VIH = VD – 0.4 V, VIL = 0.4 V
8
Rev. 1.2
Si2456/33/14
UART Time for Modem Receive Path (8N1 Mode)
8-B it Data
M ode
RX
S tart
tR TS
D0
D1
D2
D3
D4
D5
D6
D7
S top
t R TH
RTS
UART Timing for Modem Transmit Path (9N1 Mode with 9th Bit Escape)
9-B it Data
M ode
TX
S tart
D0
D1
D2
D3
D4
D5
D6
D7
t R TS
ESC
S top
t CTH
CTS
Figure 2. Asynchronous UART Serial Interface Timing Diagram
Rev. 1.2
9
Si2456/33/14
t CSS
t CSH
t AS
t AH
CS
ADDRESS = 0 or 1
A0
t RC
t RL
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
10
Rev. 1.2
Y1
1
C26
C35
RTSb/D7
RXD/RDb
TXD/WRb
CTSb/CSb
RESETb
CLKOUT/EECS/A0
D6
2
C27
1
2
3
4
5
6
7
8
9
10
11
12
AOUT/INTb
INTb/D0
RIb/D1
EESD/D2
CLKIN/XTALI
EECLK/D5
XTALO
DCD/D4
CLKOUT/EECS/A0 ESC/D3
D6
C1A
VD3.3
ISOB
GND
VD 3.3
VDA
GND
RTS/D7
VDB
RXD/RD
EESD/D2
TXD/WR
RI/D1
CTS/CS
INT/D0
RESET
AOUT/INT
Si2456/33/14
U1
ESC/D3
DCDb/D4
EECLK/D5
24
23
22
21
20
19
18
17
16
15
14
13
C37
Decoupling caps for U1 VD
C36
C3
Z4
R27
C30
D3
Rev. 1.2
R28
C9
R7
R8
1
2
3
4
5
6
7
8
U2
C18
C19
D4
Si3015
C7
C8
Z5
TSTA/QE2 TX/FILT2
TSTB/DCT NC/FILT
IGND
RX
C1B
REXT
RNG1 DCT/REXT2
RNG2
NC/REF
QB
NC/VREG2
QE
VREG
C6
16
15
14
13
12
11
10
9
C13
R9
R10
C16
C12
+
R11
D1
RV2
D2
C14 +
R12
R13
R2
+
C5
Note 5: L1,L2, C38, C39, R31, R32 are for EN55022/CISPR-22 Conduc ted Disturbance compliance.
Note 4: R27, R28, D3, D4, Z4, Z5, RV2 may be populated for enhanced lightning option.
Note 3: S ee "Billing Tone Immunity" section for optional billing tone filter (Germany, Switzerland, South Africa).
Note 2: See "Ringer Impedance" section for optional Czech Republic support.
Note 1: R12, R13 and C14 are only required if complex AC termination is used (ACT bit = 1).
C4
C1
R15
C10
R25
R26
C22
R18
Z1
C25
R24
Q4
C24
R5
R19
Refer to AN48 for Layout Guidelines
Please submit layout to Silicon Labs
for review prior to PCB fabrication.
C38
C39
Q2
R31
R32
L1
L2
Q1
R16
VCC
Q3
C20
R6
FB1
FB2
RV1
TIP
RING
Si2456/33/14
2. Typical Application Schematic
11
R17
Si2456/33/14
3. Bill of Materials: Si2456/33/14 Chipset
Component
Value
Supplier(s)
C1,C41
150 pF, 3 kV, X7R, ±20%
Novacap, Venkel, Johanson, Murata, Panasonic
C3,C13,C35,C36
0.22 µF, 16 V, X7R, ±20%
Novacap, Venkel, Johanson, Murata, Panasonic
0.1 µF, 50 V, Elec/Tant, ±20%
Venkel, Johanson, Murata, Panasonic
0.1 µF, 16 V, X7R, ±20%
Novacap, Venkel, Johanson, Murata
C7,C8
560 pF, 250 V, X7R, ±20%
Novacap, Venkel, Johanson, Murata, Panasonic
C9
22 nF, 250 V, X7R, ±20%
Novacap, Venkel, Johanson, Murata, Panasonic
1.0 µF, 16 V, Tant, ±20%
Venkel, Panasonic
0.68 µF, 16 V, X7R/Elec/Tant,
±20%
Novacap, Venkel, AUX, Murata, Panasonic
C18,C193
3.9 nF, 16 V, X7R, ±20%
Novacap, Venkel, Johanson, Murata
C20
0.01 µF, 16 V, X7R, ±20%
Novacap, Venkel, Johanson, Murata
1800 pF, 50 V, X7R, ±20%
Not installed
1000 pF, 3 kV, X7R, ±10%
Novacap, Venkel, Johanson, Murata, Panasonic
33 pF, 16 V, NPO, ±5%
Novacap, Venkel, Johanson, Murata
10 pF, 16 V, NPO, ±10%
Not Installed
47 pF, 16 V, X7R, ±10%
Venkel
Dual Diode, 300 V, 225 mA
Central Semiconductor
D3,D4
BAV99 Dual Diode, 70 V, 350 mW
Diodes Inc., OnSemiconductor, Fairchild
FB1,FB2
Ferrite Bead, 600 Ω, ±25%,
200 mA
Murata
L1,L22,5
68 μH, 120 mA, 4 Ω max, ±10%
Murata, Panasonic
Q1,Q3
A42, NPN, 300 V
OnSemiconductor, Fairchild, Zetex
Q2
A92, PNP, 300 V
OnSemiconductor, Fairchild, Zetex
BCP56, NPN, 60 V, 1/2 W
OnSemiconductor, Fairchild
C5
2
C6,C10,C16,C37
3
C12
C14
C22
2
4
C24,C25
1
C26,C27
C30
4
2,5
C38,C39
D1,D26
1
7
Q4
Notes:
1. The Si2456/33/14 design survives up to 3500 V longitudinal surges without R27, R28, D3, D4, Z4, and Z5. Adding the R27, R28, D3,
D4, Z4, and Z5 enhanced lightning options increases longitudinal surge survival to greater than 6600 V. The isolation capacitors, C1,
C4, C24, and C25, must also be rated to greater than the surge voltage. Y-class capacitors are recommended for highest surge
survival.
2. For FCC-only designs, C14, C38, C39, R12, R13, R31, and R32 are not required (leave Si3015 pin 12 unconnected); L1 and L2 may
be replaced with a short; R2 may be ±5%; with Z1 rated at 18 V, C5 may be rated at 16 V; also see Note 9.
3. If the auto answer, ring detect, and caller ID features are not used, R9, R10, C7, and C8 may be removed.
4. C22 and C30 may provide an additional improvement in emissions/immunity, depending on design and layout. Population option
recommended. See “AN70: Si2456/Si2433/Si2414/Si2403 Modem Designer’s Guide” for details.
5. Compliance with EN55022 and/or CISPR-22 conductance disturbance tests requires the following: L1, L2, C38, C39, R31, and R32;
D1 and D2 must be 400 V rated, and RV2 must be populated. See also “EN55022 and CISPR-22 Compliance” in “AN70: Si2456/
Si2433/Si2414/Si2403 Modem Designer’s Guide”.
6. Several diode bridge configurations are acceptable (suppliers include General Semi., Diodes Inc.)
7. Q4 may require copper on board to meet 1/2 W power requirement. (Contact manufacturer for details.)
8. RV2 can be installed to improve performance for multiple longitudinal surges.
9. The R7, R8, R15, and R16, R17, R19 resistors may each be replaced with a single resistor of 1.78 kΩ, 3/4 W, ±1%. For FCC-only
designs, 1.78 kΩ, 1/16 W, ±5% resistors may be used.
10. If the parallel phone detection feature is not used, R25 and R26 may be removed.
11. 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. Crystals with 50 ppm initial accuracy typically satisfy this requirement.
12
Rev. 1.2
Si2456/33/14
Component
Value
Supplier(s)
RV1
Sidactor, 275 V, 100 A
Teccor, ST Microelectronics, Microsemi, TI
RV25,8
270 V, MOV
Not Installed
402 Ω, 1/16 W, ±1%
Venkel, Panasonic
100 kΩ, 1/16 W, ±1%
Venkel, Panasonic
120 kΩ, 1/16 W, ±5%
Venkel, Panasonic
5.36 kΩ, 1/4 W, ±1%
Venkel, Panasonic
56 kΩ, 1/10 W, ±5%
Venkel, Panasonic
R2
2
R5
R6
9
R7,R8,R15,R16,R17,R19
R9,R10
3
R11
9.31 kΩ, 1/16 W, ±1%
Venkel, Panasonic
R12
2
78.7 Ω, 1/16 W, ±1%
Venkel, Panasonic
R13
2
215 Ω, 1/16 W, ±1%
Venkel, Panasonic
R18
2.2 kΩ, 1/10 W, ±5%
Venkel, Panasonic
150 Ω, 1/16 W, ±5%
Venkel, Panasonic
10 MΩ, 1/16 W, ±5%
Venkel, Panasonic
10 Ω, 1/10 W, ±5%
Venkel, Panasonic
470 Ω, 1/16 W, ±5%
Venkel, Panasonic
U1
Si2456/33/14
Silicon Labs
U2
Si3015
R24
10
R25,R26
R27,R281
2,5
R31,R32
Silicon Labs
11
Y1
4.9152 MHz, 20 pF, 100 ppm ,
150 ESR
Not Installed
Z11
Zener Diode, 43 V, 1/2 W
Vishay, OnSemiconductor, Rohm
Z4,Z51
Zener Diode, 5.6 V, 1/2 W
Vishay, OnSemiconductor, Rohm
Notes:
1. The Si2456/33/14 design survives up to 3500 V longitudinal surges without R27, R28, D3, D4, Z4, and Z5. Adding the R27, R28, D3,
D4, Z4, and Z5 enhanced lightning options increases longitudinal surge survival to greater than 6600 V. The isolation capacitors, C1,
C4, C24, and C25, must also be rated to greater than the surge voltage. Y-class capacitors are recommended for highest surge
survival.
2. For FCC-only designs, C14, C38, C39, R12, R13, R31, and R32 are not required (leave Si3015 pin 12 unconnected); L1 and L2 may
be replaced with a short; R2 may be ±5%; with Z1 rated at 18 V, C5 may be rated at 16 V; also see Note 9.
3. If the auto answer, ring detect, and caller ID features are not used, R9, R10, C7, and C8 may be removed.
4. C22 and C30 may provide an additional improvement in emissions/immunity, depending on design and layout. Population option
recommended. See “AN70: Si2456/Si2433/Si2414/Si2403 Modem Designer’s Guide” for details.
5. Compliance with EN55022 and/or CISPR-22 conductance disturbance tests requires the following: L1, L2, C38, C39, R31, and R32;
D1 and D2 must be 400 V rated, and RV2 must be populated. See also “EN55022 and CISPR-22 Compliance” in “AN70: Si2456/
Si2433/Si2414/Si2403 Modem Designer’s Guide”.
6. Several diode bridge configurations are acceptable (suppliers include General Semi., Diodes Inc.)
7. Q4 may require copper on board to meet 1/2 W power requirement. (Contact manufacturer for details.)
8. RV2 can be installed to improve performance for multiple longitudinal surges.
9. The R7, R8, R15, and R16, R17, R19 resistors may each be replaced with a single resistor of 1.78 kΩ, 3/4 W, ±1%. For FCC-only
designs, 1.78 kΩ, 1/16 W, ±5% resistors may be used.
10. If the parallel phone detection feature is not used, R25 and R26 may be removed.
11. 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. Crystals with 50 ppm initial accuracy typically satisfy this requirement.
Rev. 1.2
13
Si2456/33/14
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 kbps
12.0 kbps
9600 bps
7200 bps
4800 bps
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.32bis
ITU-T V.34 or V.32bis
ITU-T V.34, V.32bis, or V.29
ITU-T V.34 or V.32bis
ITU-T V.34 or V.32bis
ITU-T V.34 or V.22bis
ITU-T V.22bis, V.23, or Bell 212A
ITU-T V.21
Bell 103
Notes:
1. Supported on Si2456 only.
2. Supported on Si2456 and Si2433 only.
14
Rev. 1.2
Si2456/33/14
Table 7. Protocol Characteristics (Continued)
Item
Data Format
Bit asynchronous
Compatibility
Specification
Selectable 8, 9, 10, or 11 bits per character
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 kbps
12.0 kbps
9600 bps
9600 bps
9600 bps
7200 bps
4800 bps
2400 bps
1200 bps
0 to 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 0–300 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.32bis
ITU-T V.32
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%
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 Si2456 only.
2. Supported on Si2456 and Si2433 only.
Rev. 1.2
15
Si2456/33/14
Table 7. Protocol Characteristics (Continued)
Item
Receive Carrier
ITU-T V.901
ITU-T V.342
ITU-T V.32bis
ITU-T V.32
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
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.32bis 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
Connection Options
Automatic Adaptive
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 Part 68
Pulse Dial Ratio
Make/Break: 39/61%
Ring Cadence
On 2 seconds; Off 4 seconds
Call Progress Monitor
BUSY
CONNECT (rate)
NO CARRIER
NO DIALTONE
OK
RING
RINGING
Notes:
1. Supported on Si2456 only.
2. Supported on Si2456 and Si2433 only.
16
Rev. 1.2
Si2456/33/14
4. Functional Description
4.1. Digital Interface
The ISOmodem® chipset is a complete embeddedmodem
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, a modem controller, on-chip RAM and
ROM, an analog front end (AFE), a DAA, and analog
output.
The ISOmodem chipset digital I/O can be configured as
either a serial UART interface with flow control or as a
parallel 8-bit interface.
The Si2456/33/14 accepts standard modem AT
commands and provides connect rates up to 56/33.6/
14.4 kbps full-duplex over the Public Switched Telephone
Network (PSTN). The Si2456/33/14 features a complete
set of modem protocols including all ITU-T standard
formats up to 56 kbps.
The Si2456/33/14 provides numerous additional features
for embedded modem applications. The modem includes
full caller ID detection and decoding for global standards.
Call progress is supported through echoing result codes
and is also programmable to meet global settings.
Because the Si2456/33/14 integrates the DAA, analog
features, such as parallel phone detect, overcurrent
detection, and global PTT compliance with a single
design, are included.
This device is ideal for embedded modem applications
due to its small board space, low power consumption,
and global compliance. The Si2456/33/14 solution
includes a silicon DAA using Silicon Laboratories’
proprietary capacitive isolation 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
Si2456/33/14 has been designed to meet the most
stringent worldwide requirements for out-of-band energy,
billing-tone immunity, lightning surges, and safety
requirements.
The Si2456/33/14 is designed to be rapidly incorporated
into existing modem applications. The device interfaces
directly through either a serial UART to a microcontroller
or to a PC through a standard RS-232 transceiver. This
interface allows for PC evaluation of the modem
immediately upon powerup via the AT commands using
standard terminal software. The Si2456/33/14 also
provides an 8-bit parallel port.
The Si2456/33/14 solution requires only a few low-cost
discrete components to achieve global compliance. See
the "Typical Application Schematic" on page 11.
Selection of a serial or parallel I/O interface is
determined by the state of AOUT/INT (Si2456/33/14,
pin 13) during the rising edge of RESET. An internal
pullup resistor forces the default state to serial mode
operation. An external 10 kΩ pulldown resistor can be
connected to AOUT/INT to force selection of parallel
mode. Additionally, when selecting parallel mode, CS
should remain high until after the rising edge of RESET.
Configuration of pins 3, 4, 8–11, 13–16, and 22–24 is
determined by this interface selection.
4.2. Serial Interface
The ISOmodem chipset supports Data Terminal
Equipment (DTE) rates up to 307.2 kbps with the
standard serial UART format. Upon powerup, the UART
defaults to a 19.2 kbps baud rate. If a pulldown resistor
≤ 10 kΩ is placed between D2 (Si2456/33/14, pin 16)
and GND (Si2456/33/14, pin 6), the DTE rate is set by
the autobaud feature after reset.
The serial interface also provides a hardware pin, DCD
(data carrier detect), which remains low as long as the
Si2456/33/14 is connected.
The INT interrupt pin can be programmed to alert the
host of changes to the interrupts listed in I/O Control 0
(U70).
4.2.1. Autobaud
The ISOmodem chipset includes an automatic baud
rate detection feature that allows the host to start
transmitting data at any standard DTE rate from
300 bps to 307.2 kbps. This feature is enabled by
placing a pulldown resistor 140 mA in all modes except CTR21
Overload > 54 mA in CTR21 mode
Rev. 1.2
59
Si2456/33/14
U7A GENA
Bit
D15 D14 D13 D12 D11 D10
D9
D8
D7
D6
Name
DOP ADD
Type
R/W R/W
D5
D4
D3
D2
D1
D0
HDLC FAST
R/W
R/W
Reset settings = 0x0000
Bit
Name
Function
15:8
Reserved
7
DOP
Dial or Pulse.
0 = Normal ATDTW operation
1 = Use ATDTW for Pulse/Tone Dial Detection (see also ATDW command)
6
ADD
Adaptive Dialing
1 = Enable
0 = Disable
Attempt DTMF dial, then fall back to pulse dialing if unsuccessful. First digit is dialed as
DTMF. If a dialtone is still present after two seconds, the Si2456/33/14 will redial the first digit
and remaining digits as pulse. If a dialtone is not present after two seconds, the Si2456/33/14
will dial the remaining digits as DTMF.
5:2
Reserved
1
HDLC
Synchronous Mode.*
0 = Normal asynchronous mode.
1 = Transparent HDLC mode.
0
FAST
Fast Connect.*
0 = Normal modem handshake timing per ITU/Bellcore standards.
1 = Fast connect modem handshake timing.
Read returns to zero.
Read returns to zero.
*Note: When V22HD, HDLC, or FAST bits are set, \N0 (wire mode) must be used.
60
Rev. 1.2
Si2456/33/14
U7C GENC
Bit
D15 D14 D13 D12 D11 D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Name
RIGPO
RIGPOEN
Type
R
R/W
Reset settings = 0x0000
Bit
15:5
4
3:1
0
Name
Reserved
RIGPO
Function
Reads returns to zero.
RI.
RI (pin 15), follows this bit when RIGPIOEN = 1b.
Reserved Reads returns to zero.
RIGPOEN 0 = RI indicates valid ring signal (Normal ring-indicator mode).
1 = RI (Pin 15) can be used as a general-purpose output and follows U7C[4] (RIGPO).
Rev. 1.2
61
Si2456/33/14
U7D GEND
Bit
D15 D14
D13
D12 D11 D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
Name
LVFE
LLV AUSDC
ATZD
FDP
Type
R/W
R/W
R/W
R/W
R/W
Reset settings = 0x0000
Bit
15:14
13
Name
Reserved
LVFE
12:11
10
Reserved
LLV
9
AUSDC
8:2
1
Reserved
ATZD
0
FDP
Function
Reads returns to zero.
LVCS Filter Enable.
0 = Normal operation
1 = Enables optional filtering on LVCS to mitigate the effect of 50/60 Hz noise on tip/ring voltage.
Read returns zero.
0 = Normal operation.
1 = Enables an optional algorithm for countries, such as Japan and Malaysia, with low loop
voltage. Also set U67[3:2] (DCT) = 00b, U69[4] VOL = 1b, and U52 = 0x0002 before going offhook. When the modem goes off-hook, it samples LVCS and changes DCT and VOL as necessary to maximize transmit levels and optimize distortion.
0 = Normal operation.
1 = Causes the modem to go off-hook in Japan mode and then revert to FCC mode after
500 ms. This allows the modem to meet the Australian line seizure requirements while allowing the maximum transmit power (optional for Australia and when DCT = 01b).
Reads returns to zero.
ATZ Disable.
0 = ATZ functions normally.
1 = Disable ATZ command. This may be used to ensure modem settings are not lost in some
systems.
FSK Data Processing.
0 = FSK data processing stops when carrier is lost.
1 = FSK data processing continued for 2 bytes after carrier is lost.
UAA V.29 Mode
Bit
D15 D14 D13 D12 D11 D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
Name
V29EMA
Type
R/W
Reset settings = 0x0000
Bit
15:2
1
Name
Reserved
V29ENA
0
Reserved
62
Function
Read returns zero.
0 disables V.29.
1 enables V.29
Read returns zero.
Rev. 1.2
D0
Si2456/33/14
7. Parallel Interface Registers
Parallel Interface 0 (0x00)
Bit
D7
D6
D5
D4
D3
Name
TX/RX
Type
R/W
D2
D1
D0
Reset settings = 0x00
Bit
Name
Function
7:0
TX/RX
Parallel Interface Transmit/Receive.
This register functions similarly to the serial port TX pin on writes to the parallel port, and similarly to the serial port RX pin on reads from the parallel port.
Rev. 1.2
63
Si2456/33/14
Parallel Interface 1 (0x01)
Bit
D7
D6
D5
D4
D3
D2
D1
D0
Name
RXF
TXE
REM
INTM
INT
ESC
RTS
CTS
Type
R
R
R
R/W
R
R/W
R/W
R
Reset settings = 0110_0011
Bit
Name
Function
7
RXF
Receive FIFO Almost Full (status).
0 = Receive FIFO (12 deep) contains three or more empty locations (RXF ≤ 9). The host can
clear the RXF interrupt without emptying the RX FIFO by writing a 0 to the RXF bit. This will
disable the RXF interrupt until the host has emptied the FIFO.
1 = Receive FIFO contains two or less empty locations (RXF ≥ 10).
6
TXE
Transmit FIFO Almost Empty (status).
0 = Transmit FIFO (14 deep) contains three or more characters (TXF ≥ 3).
1 = Transmit FIFO contains two or less characters (TXF ≤ 2). TXE interrupt will not trigger if
the CTS bit is inactive. Therefore, the host does not need to poll CTS while waiting for transmit FIFO to empty. TXE can be cleared by writing it to 0.
5
REM
Receive FIFO Empty.
0 = Receive FIFO has valid data.
1 = Receive FIFO empty.
Note: If the interim timer (see PTMR - U6F, bits 7:0) set by PTMR expires, it will cause an interrupt. This
interrupt will not set RXF, TXE, or INT. The interrupt handler on the host should then verify that
REM = 0 and begin to empty the receive FIFO (Parallel Interface 0 register) until REM = 1.
64
4
INTM
Interrupt Mask.
0 = In parallel mode, the INT pin is triggered by a rising edge on RXF or TXE only (default).
1 = In parallel mode, the INT pin is triggered by a rising edge on RXF, TXE, or INT.
3
INT
Interrupt.
0 = No interrupt has occurred.
1 = Indicates that an interrupt (CID, OCD, PPD, RI, or DCD from U70) has occurred. This bit is
cleared via the AT:I command.
2
ESC
Escape.
Operation of this bit in parallel mode is functionally-equivalent to the ESC pin in serial mode.
1
RTS
Request-to-Send.
Operation of this bit in parallel mode is functionally equivalent to the RTS pin in serial mode.
Use of the CTS and RTS bits (as opposed to the TXE and RXF bits) allows the flow control
between the host and the Si2456/33/14 to operate 1 byte at a time rather than in blocks.
0
CTS
Clear-to-Send.
Operation of this bit in parallel mode is functionally-equivalent to the CTS pin in serial mode.
Use of the CTS and RTS bits (as opposed to the TXE and RXF bits) allows the flow control
between the host and the Si2456/33/14 to operate 1 byte at a time, rather than in blocks.
Rev. 1.2
Si2456/33/14
8. Pin Descriptions: Si2456/33/14
CLKIN/XTALI
1
24
EECLK/D5
XTALO
2
23
DCD/D4
CLKOUT/EECS/AO
3
22
ESC/D3
D6
4
21
C1A
VD3.3
5
6
20
19
ISOB
GND
VDA
7
18
GND
RTS/D7
8
17
VDB
RXD/RD
9
16
EESD/D2
TXD/WR
10
15
RI/D1
CTS/CS
11
14
INT/DO
12
13
AOUT/INT
RESET
VD3.3
Pin #
Pin Name
Description
1
CLKIN/XTALI
Clock Input/Crystal Oscillator Pin.
This pin provides support for parallel-resonant, AT-cut crystals. XTALI also acts
as an input in the event that an external clock source is used in place of a crystal.
A 4.9152 MHz crystal or 4.9152 MHz clock is required.
2
XTALO
Crystal Oscillator Pin.
This pin provides support for parallel-resonant AT-cut crystals. XTALO serves as
the output of the crystal amplifier.
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
D6
Data Bit.
Bidirectional parallel bus data bit 6 in parallel mode.
5, 19
VD3.3
Digital Supply Voltage.
Provides the 3.3 V digital supply voltage to the Si2456/33/14.
6, 18
GND
Ground.
Connects to the system digital ground.
7,17
VDA, VDB
8
RTS/D7
Request-to-Send/Data Bit.
Request-to-send (for flow control) in serial mode. Bidirectional parallel bus data
bit 7 in parallel mode.
9
RXD/RD
Receive Data/Read Enable.
Data output to DTE RXD pin in serial mode. Active low read enable pin in parallel
mode.
Digital Rail.
Pin provides decoupling for the internal power supplies.
Rev. 1.2
65
Si2456/33/14
Pin #
Pin Name
Description
10
TXD/WR
Transmit Data/Write Enable.
Data input from DTE TXD pin in serial mode. Active low write-enable pin in parallel mode.
11
CTS/CS
Clear-to-Send/Chip Select.
Active low clear-to-send (for flow control) in serial 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
AOUT/INT
14
INT/D0
Interrupt Output/Data Bit.
Active low interrupt output in serial mode. Bidirectional parallel bus data bit 0 in
parallel mode.
15
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.
16
EESD/D2
EEPROM Serial Data Input/Output/Data Bit.
Bidirectional Input/Output to SPI EEPROM in serial mode. Bidirectional parallel
bus data bit 2 in parallel mode.
20
ISOB
Bias Voltage.
This pin provides decoupling for the power supply.
21
C1A
Isolation Capacitor 1A.
Connects to one side of the isolation capacitor, C1.
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
EECLK/D5
EEPROM Clock/Data Bit.
Clock output for SPI EEPROM in serial mode. Bidirectional parallel bus data bit 5
in parallel mode.
66
Analog Output/Interrupt Output.
Analog output in serial mode. Active low interrupt output in parallel mode.
Rev. 1.2
Si2456/33/14
9. Pin Descriptions: Si3015
QE2
DCT
IGND
C1B
RNG1
RNG2
QB
QE
1
2
3
4
5
6
7
8
16
15
FILT2
FILT
14
13
RX
REXT
12
11
REF
10
9
VREG2
VREG
REXT2
Pin #
Pin Name
Description
1
QE2
Transistor Emitter 2.
Connects to the emitter of Q4.
2
DCT
DC Termination.
Provides dc termination to the telephone network.
3
IGND
Isolated Ground.
Connects to ground on the line-side interface. Also connects to capacitor C2.
4
C1B
Isolation Capacitor 1B.
Connects to one side of isolation capacitor C1.
5
RNG1
Ring 1.
Connects through a capacitor to the TIP lead of the telephone line. Provides the ring
and caller ID signals to the modem.
6
RNG2
Ring 2.
Connects through a capacitor to the RING lead of the telephone line. Provides the ring
and caller ID signals to the modem.
7
QB
Transistor Base.
Connects to the base of transistor Q3.
8
QE
Transistor Emitter.
Connects to the emitter of transistor Q3.
9
VREG
Voltage Regulator.
Connects to an external capacitor to provide bypassing for an internal power supply.
10
VREG2
Voltage Regulator 2.
Connects to an external capacitor to provide bypassing for an internal power supply.
11
REF
12
REXT2
External Resistor 2.
Sets the complex ac termination impedance.
13
REXT
External Resistor.
Sets the real ac termination impedance.
Reference.
Connects to an external resistor to provide a high-accuracy reference current.
Rev. 1.2
67
Si2456/33/14
Pin #
Pin Name
14
RX
Receive Input.
Serves as the receive side input from the telephone network.
15
FILT
Filter.
Provides filtering for the dc termination circuits.
16
FILT2
Filter 2.
Provides filtering for the bias circuits.
68
Description
Rev. 1.2
Si2456/33/14
10. Ordering Guide
Chipset
Description
System-Side
Line-Side
Temperature
Si2456
Commercial
Si2456-KT
Si3015-KS
0 to 70 °C
Si2456
Commercial lead-free
Si2456-FT
Si3015-F-FS
0 to 70 °C
Si2456
Industrial
Si2456-BT
Si3015-BS
–40 to 85 °C
Si2433
Commercial
Si2433-KT
Si3015-KS
0 to 70 °C
Si2433
Commercial lead-free
Si2433-FT
Si3015-F-FS
0 to 70 °C
Si2433
Industrial
Si2433-BT
Si3015-BS
–40 to 85 °C
Si2414
Commercial
Si2414-KT
Si3015-KS
0 to 70 °C
Si2414
Commercial lead-free
Si2414-FT
Si3015-F-FS
0 to 70 °C
Si2414
Industrial
Si2414-BT
Si3015-BS
–40 to 85 °C
Rev. 1.2
69
Si2456/33/14
11. Package Outline: 24-Pin TSSOP
Figure 8 illustrates the package details for the Si2456/33/14. Table 16 lists the values for the dimensions shown in
the illustration.
E
H
θ
L
B
D
A
e
A1
γ
C
Approximate device weight is 115.7 mg.
Figure 8. 24-Pin Thin Shrink Small Outline Package (TSSOP)
Table 16. Package Diagram Dimensions
Millimeters
Symbol
Min
Max
Typical*
A
—
1.20
3
A1
0.05
0.15
3
B
0.19
0.30
C
0.09
0.20
D
7.70
7.90
E
4.30
4.50
e
0.65 BSC
H
6.40 BSC
L
0.45
0.75
θ
0°
8°
γ
3
3
0.10
*Note: To guarantee coplanarity (γ), the
parameters marked “Typical” may be
exceeded.
70
Rev. 1.2
Si2456/33/14
12. Package Outline: 16-Pin SOIC
Figure 9 illustrates the package details for the Si3015. Table 17 lists the values for the dimensions shown in the
illustration.
16
9
h
E
H
0.010
θ
1
8
B
GAUGE PLANE
L
Detail F
D
C
A
e
A1
See Detail F
γ
Seating Plane
Figure 9. 16-pin Small Outline Integrated Circuit (SOIC) Package
Table 17. Package Diagram Dimensions
A
Millimeters
Min
Max
1.35
1.75
A1
.10
.25
B
.33
.51
C
.19
.25
D
9.80
10.00
E
3.80
4.00
e
1.27 BSC
—
H
5.80
6.20
Symbol
h
.25
.50
L
.40
1.27
γ
—
0.10
θ
0º
8º
Typical*
3
3
3
3
*Note: Typical parameters are for information
purposes only.
Rev. 1.2
71
Si2456/33/14
DOCUMENT CHANGE LIST
Revision 1.0 to Revision 1.1
Updated "Functional Block Diagram" on page 1.
Updated Table 6 on page 8.
Expanded +GCI country codes in Table 8 on
page 22.
Updated S-registers S43 and S44 in Table 14 on
page 41.
Added U-register “UAA V.29 Mode” on page 62.
Updated default register values for U66.
Updated U-register U7D.
Revision 1.1 to Revision 1.2
Updated "Ordering Guide" on page 69.
72
Rev. 1.2
Si2456/33/14
NOTES:
Rev. 1.2
73
Si2456/33/14
CONTACT INFORMATION
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Austin, TX 78735
Tel: 1+(512) 416-8500
Fax: 1+(512) 416-9669
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Email: ISOinfo@silabs.com
Internet: www.silabs.com
The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice.
Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from
the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features
or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Silicon Laboratories assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are not designed, intended, or authorized for use in applications intended to
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74
Rev. 1.2