SI4708-C Datasheet, PDF (11/40 Pages) Silicon Laboratories – BROADCAST FM RADIO TUNER FOR PORTABLE APPLICATIONS

Si4708/09-C
Table 7. FM Receiver Characteristics^1,2 (Continued)
(V_D = V_A = 2.7 to 5.5 V, V_IO = 1.62 to 3.6 V, T_A = –20 to 85 °C)
Parameter
Symbol Test Condition
Min
Typ Max
Unit
Mono/Stereo Switching Level^3,8,12
Audio Mono S/N^3,4,5,6,9
Audio Stereo S/N^3,5,6,8
Audio THD^3,4,9,12
De-emphasis Time Constant¹³
BLNDADJ = 10
10 dB stereo separation
—
34
— dBµVEMF
55
60
—
dB
BLNDADJ = 10
—
58
—
dB
—
0.1
0.5
%
DE = 0
70
75
80
µs
Audio Common Mode Voltage¹⁴
DE = 1
ENABLE = 1
45
50
54
µs
0.65 0.8
0.9
V
Audio Common Mode Voltage¹⁴
Audio Output Load Resistance^8,14
Audio Output Load Capacitance^8,14
Seek/Tune Time^8,11
Powerup Time¹⁵
RSSI Offset¹⁶
ENABLE = 0
AHIZEN = 1
— 0.5 x V_IO —
V
R_L
Single-ended
10
—
—
k
C_L
Single-ended
—
—
50
pF
SPACE[1:0] = 0x,
—
—
60
ms/
RCLK
channel
tolerance = 200 ppm,
(x = 0 or 1)
From powerdown
—
—
110
ms
(Write ENABLE bit to 1)
Input levels of 8 and –3
—
3
dB
60 dBµV at RF input
Notes:
1. Additional testing information is available in Application Note AN388. Volume = maximum for all tests.
2. Important Note: To ensure proper operation and FM receiver performance, follow the guidelines in “AN350: Si4708/09
Antenna, Schematic, Layout, and Design Guidelines.” Silicon Laboratories will evaluate schematics and layouts for
qualified customers.
3. F_MOD = 1 kHz, 75 µs de-emphasis
4. MONO = 1, and L = R unless noted otherwise.
5. f = 22.5 kHz.
6. B_AF = 300 Hz to 15 kHz, A-weighted.
7. Typical sensitivity with headphone matching network.
8. Guaranteed by characterization.
9. V_EMF = 1 mV.
10. |f₂ – f₁| > 1 MHz, f₀ = 2 x f₁ – f₂. AGC is disabled by setting AGCD = 1. Refer to "6. Register Descriptions" on page
20.
11. The channel spacing is selected with the SPACE[1:0] bits. Refer to "6. Register Descriptions" on page 20. Seek/Tune
timing is guaranteed for 100 and 200 kHz channel spacing. ±50 ppm PCLK tolerance required for 50 kHz channel
spacing.
12. f = 75 kHz.
13. The de-emphasis time constant is selected with the DE bit. Refer to "6. Register Descriptions" on page 20.
14. At LOUT and ROUT pins.
15. Do not enable STC interrupts before the powerup time is complete. If STC interrupts are enabled before the powerup
time is complete, an interrupt will be generated within the powerup interval when the initial default tune operation is
complete. See "AN349: Si4708/09 Programming Guide" for more information.
16. Minimum and maximum at room temperature (25 °C).
Rev. 1.2
11