SI4840-DEMO Datasheet, PDF (5/22 Pages) Silicon Laboratories – Si4840/44 DEMO BOARD USERS GUIDE

Si4840/44-DEMO
Audio output test point:
For general specification test, TP3 is the recommended audio signal test point. The audio test instrument should
be connected to TP3 to get more accurate test results. J5 can also be used as an audio test point, but the test
results may not be entirely accurate under some circumstances.
TP3:
1
GND
2
Lout
3
Rout
Main components:
U1: Silicon Laboratories Si484x FM/AM/SW ATDD tuner
U2: Audio amplifier
U3: MCU
LCD: The digital display of tuning information
Control interface:
VR1: Frequency tuning wheel
VR2: Volume control wheel
S3~S10: The keypad for human interface
S2: Band slide switch for FM, AM, and SW
1 2 3 4 5 6 7 8 9 10 11 12
Band definition:
1: FM1 (87–108 MHz), De-emphasis=75 us, ST indication=6 dB separation@20 dBµV
2: FM5 (64–87 MHz), De-emphasis=75 us, ST indication=6 dB separation@20 dBµV
3: AM1 (520–1710 kHz), 10 kHz spacing
4: AM2 (522–1620 kHz), 9 kHz spacing
5: SW1 (5.6–6.4 MHz)
6: SW3 (6.8–7.6 MHz)
7: SW5 (9.2–10.0 MHz)
8: SW7 (11.45–12.25 MHz)
9: SW9 (13.4–14.2 MHz)
10: SW11 (15–15.9 MHz)
11: SW13 (17.1–18 MHz)
12: SW15 (21.2–22 MHz)
Rev 0.1
5