Si2403
Component
Value
Supplier(s)
5,8
RV2
270 V, MOV
Not Installed
2
R2
402 Ω, 1/16 W, ±1%
100 kΩ, 1/16 W, ±1%
120 kΩ, 1/16 W, ±5%
5.36 kΩ, 1/4 W, ±1%
56 kΩ, 1/10 W, ±5%
9.31 kΩ, 1/16 W, ±1%
78.7 Ω, 1/16 W, ±1%
215 Ω, 1/16 W, ±1%
2.2 kΩ, 1/10 W, ±5%
150 Ω, 1/16 W, ±5%
10 MΩ, 1/16 W, ±5%
10 Ω, 1/10 W, ±5%
470 Ω, 1/16 W, ±5%
Si2403
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Venkel, Panasonic
Silicon Labs
R5
R6
9
R7,R8,R15,R16,R17,R19
3
R9,R10
R11
2
R12
2
R13
R18
R24
10
R25, R26
1
R27, R28
2,5
R31, R32
U1
U2
Y1
Si3015
Silicon Labs
11
4.9152 MHz, 20 pF, 100 ppm ,
150 ESR
Not Installed
1
Z1
Zener Diode, 43 V, 1/2 W
Zener Diode, 5.6 V, 1/2 W
Vishay, OnSemiconductor, Rohm
Vishay, OnSemiconductor, Rohm
1
Z4,Z5
Notes:
1. The Si2403 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
SILICON [ SILICON ]
