Si473x-B20
Rev. 0.5 11
Table 7. FM Receiver Characteristics
1,2
(V
DD
= 2.7 to 5.5 V, V
IO
= 1.5 to 3.6 V, T
A
= –20 to 85 °C)
Parameter Symbol Test Condition Min Typ Max Unit
Input Frequency f
RF
76 — 108 MHz
Sensitivity with Headphone
Network
3,4,5
(S+N)/N = 26 dB — 2.2 3.5 µV EMF
Sensitivity with 50 Network
3,4,5,6
(S+N)/N = 26 dB — 1.1 — µV EMF
RDS Sensitivity
6
f = 2 kHz,
RDS BLER < 5%
—15—µV EMF
LNA Input Resistance
6,7
345k
LNA Input Capacitance
6,7
456pF
Input IP3
6,8
100 105 — dBµV EMF
AM Suppression
3,4,6,7
m = 0.3 40 50 — dB
Adjacent Channel Selectivity
±200 kHz 35 50 — dB
Alternate Channel Selectivity
±400 kHz 60 70 — dB
Spurious Response Rejection
6
In-band 35 — — dB
Audio Output Voltage
3,4,7
72 80 90 mV
RMS
Audio Output L/R Imbalance
3,7,9
—— 1 dB
Audio Frequency Response Low
6
–3 dB — — 30 Hz
Audio Frequency Response High
6
–3 dB 15 — — kHz
Audio Stereo Separation
7,9
25 — — dB
Audio Mono S/N
3,4,5,7,10
55 63 — dB
Audio Stereo S/N
4,5,7,10,11
—58— dB
Audio THD
3,7,9
—0.10.5 %
De-emphasis Time Constant
6
FM_DEEMPHASIS = 2 70 75 80 µs
FM_DEEMPHASIS = 1 45 50 54 µs
Audio Output Load Resistance
6,10
R
L
Single-ended 10 — — k
Audio Output Load Capacitance
6,10
C
L
Single-ended — — 50 pF
Notes:
1. Additional testing information is available in “AN388: Si470x/1x/2x/3x/4x Evaluation Test Board Procedure.”
Volume = maximum for all tests. Tested at RF = 98.1 MHz.
2. To ensure proper operation and receiver performance, follow the guidelines in “AN383: Si47xx Antenna, Schematic,
Layout and Design Guidelines.” Silicon Laboratories will evaluate schematics and layouts for qualified customers.
3. F
MOD
=1kHz, 75µs de-emphasis, MONO = enabled, and L = R unless noted otherwise.
4. f = 22.5 kHz.
5. B
AF
= 300 Hz to 15 kHz, A-weighted.
6. Guaranteed by characterization.
7. V
EMF
=1 mV.
8. |f
2
– f
1
| > 2 MHz, f
0
=2xf
1
– f
2
. AGC is disabled.
9. f = 75 kHz.
10. At L
OUT
and R
OUT
pins.
11. Analog audio output mode.
12. At temperature (25°C).
