SI4704-D50-GM [SILICON]

Baseband Circuit, CMOS, QFN-20;
SI4704-D50-GM
型号: SI4704-D50-GM
厂家: SILICON    SILICON
描述:

Baseband Circuit, CMOS, QFN-20

电信 电信集成电路
文件: 总34页 (文件大小:1345K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
Si4704/05-D50  
BROADCAST FM RADIO RECEIVER FOR CONSUMER  
ELECTRONICS  
Features  
Worldwide FM band support  
(64–108 MHz)  
RDS/RBDS decoding engine  
(Si4705 only)  
Lowest power consumption  
Received signal quality indicators  
On-chip tuned resonance for  
embedded antenna support  
Multipath detection and mitigation  
FM Hi-cut control  
Advanced FM stereo-mono blend  
Advanced audio processing  
Not EN 55020 compliant*  
Automatic gain control (AGC)  
Integrated FM LNA  
Image-rejection mixer  
Frequency synthesizer with  
integrated VCO  
Low-IF direct conversion with no  
external ceramic filters  
2.7 to 5.5 V supply voltage  
Dual 1.8 and 2.7 V power supplies  
Stereo audio out  
I2S Digital audio out  
20-pin 3 x 3 mm QFN package  
Pb-free/RoHS compliant  
Ordering Information:  
See page 27.  
Pin Assignments  
Si4704/05-GM  
(Top View)  
*Note: *For consumer electronics applications that require EN 55020 compliance,  
use Si4704/05-D60.  
Applications  
Cellular handsets  
Portable media devices  
Dedicated data receiver  
Personal navigation devices (PND)  
GPS-enabled handsets and portable  
devices  
20 19 18 17  
NC  
FMI  
1
16  
2
15 DOUT  
14 LOUT  
13 ROUT  
12 GND  
11 VA  
RFGND  
LPI  
3
4
5
GND  
PAD  
Description  
RST  
The Si4704/05-D50 FM/RDS/RDBS receivers provide the highest performance  
and lowest power consumption available for portable devices today. The 100%  
CMOS IC integrates the complete FM and data receiver function from antenna to  
analog or digital audio and data out in a single 3 x 3 mm 20-pin QFN.  
6
7
8
9
10  
Functional Block Diagram  
This product, its features, and/or its  
architecture is covered by one or  
more of the following patents, as well  
as other patents, pending and  
issued, both foreign and domestic:  
7,127,217; 7,272,373; 7,272,375;  
7,321,324; 7,355,476; 7,426,376;  
7,471,940; 7,339,503; 7,339,504.  
FM Antenna  
Si4704/05  
ADC  
ADC  
DAC  
FMI  
LOUT  
ROUT  
LNA  
AGC  
PGA  
DSP  
RFGND  
DAC  
GPO  
LPI  
0/90  
DCLK  
DOUT  
DFS  
RDS  
(Si4705)  
32.768 kHz  
(TYP)  
RCLK  
RSSI  
AFC  
REG  
CONTROL  
INTERFACE  
VA  
2.7–5.5 V  
XTAL  
OSC  
Rev. 1.0 12/10  
Copyright © 2010 by Silicon Laboratories  
Si4704/05-D50  
Si4704/05-D50  
2
Rev. 1.0  
Si4704/05-D50  
TABLE OF CONTENTS  
Section  
Page  
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4  
2. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15  
3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16  
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17  
4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17  
4.2. FM Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18  
4.3. Stereo Audio Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18  
4.4. Received Signal Qualifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18  
4.5. De-emphasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.6. Volume Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.7. Stereo DAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.8. Soft Mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.9. FM Hi-Cut Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.10. Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.11. Seek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19  
4.12. Digital Audio Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20  
4.13. Embedded Antenna Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22  
4.14. RDS Decoder (Si4705 Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22  
4.15. Reference Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22  
4.16. Control Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23  
4.17. GPO Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24  
4.18. Reset, Powerup, and Powerdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24  
4.19. Programming with Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24  
5. Commands and Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25  
6. Pin Descriptions: Si4704/05-GM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26  
7. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27  
8. Package Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28  
8.1. Si4704 Top Mark . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28  
8.2. Si4705 Top Mark . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28  
8.3. Top Mark Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28  
9. Package Outline: Si4704/05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29  
10. PCB Land Pattern: Si4704/05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30  
11. Additional Reference Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32  
Document Change List: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33  
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34  
Rev. 1.0  
3
Si4704/05-D50  
1. Electrical Specifications  
Table 1. Recommended Operating Conditions*  
Parameter  
Symbol  
Test Condition  
Min  
2.7  
Typ  
Max  
5.5  
3.6  
Unit  
V
Analog Supply Voltage  
V
A
Digital and Interface Supply Voltage  
V
1.62  
10  
V
D
Analog Power Supply Powerup Rise  
Time  
V
µs  
ARISE  
Digital Power Supply Powerup Rise  
Time  
V
10  
µs  
DRISE  
Ambient Temperature  
T
–20  
25  
85  
C  
A
*Note: All minimum and maximum specifications are guaranteed and apply across the recommended operating conditions.  
Typical values apply at VA = 3.3 V and 25 C unless otherwise stated. Parameters are tested in production unless  
otherwise stated.  
Table 2. Absolute Maximum Ratings1,2  
Parameter  
Symbol  
Value  
–0.5 to 5.8  
–0.5 to 3.9  
10  
Unit  
V
Analog Supply Voltage  
V
A
Digital and Interface Supply Voltage  
V
V
D
3
Input Current  
I
mA  
V
IN  
3
Input Voltage  
V
T
–0.3 to (V + 0.3)  
IN  
IO  
Operating Temperature  
Storage Temperature  
–40 to 95  
–55 to 150  
0.4  
C  
C  
OP  
T
STG  
4
RF Input Level  
V
pK  
Notes:  
1. 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 beyond  
recommended operating conditions for extended periods may affect device reliability.  
2. The Si4704/05 devices are high-performance RF integrated circuits with certain pins having an ESD rating of < 2 kV  
HBM. Handling and assembly of these devices should only be done at ESD-protected workstations.  
3. For input pins DFS, SCLK, SEN, SDIO, RST, RCLK, GPO1, GPO2, GPO3, and DCLK.  
4. At RF input pins FMI and LPI.  
4
Rev. 1.0  
Si4704/05-D50  
Table 3. DC Characteristics  
(VA = 2.7 to 5.5 V, VD = 1.62 to 3.6 V, TA = –20 to 85 °C)  
Parameter  
Symbol  
Test Condition  
Min  
Typ  
Max  
Unit  
FM Receiver to Line Output  
V Supply Current  
I
7.5  
8.5  
8.4  
9.7  
11.1  
11.1  
mA  
mA  
mA  
A
FMVA  
FMVD  
FMVD  
1
V Supply Current  
I
I
Digital Output Mode  
D
V Supply Current  
Analog Output Mode  
D
Powerdown and Interface  
V Powerdown Current  
I
4
15  
10  
µA  
µA  
V
A
DDPD  
V Powerdown Current  
I
SCLK, RCLK inactive  
3
D
IOPD  
2
2
High Level Input Voltage  
V
0.7 x V  
–0.3  
–10  
V + 0.3  
D
IH  
D
2
Low Level Input Voltage  
V
0.3 x V  
10  
V
IL  
D
High Level Input Current  
I
V
= V = 3.6 V  
µA  
µA  
IH  
IN  
D
2
Low Level Input Current  
I
V
= 0 V,  
IN  
–10  
10  
IL  
V = 3.6 V  
D
3
High Level Output Voltage  
V
I
= 500 µA  
0.8 x V  
V
V
OH  
OUT  
OUT  
D
3
Low Level Output Voltage  
V
I
= –500 µA  
0.2 x V  
OL  
D
Notes:  
1. Guaranteed by characterization.  
2. For input pins SCLK, SEN, SDIO, RST, RCLK, DCLK, DFS, GPO1, GPO2, and GPO3.  
3. For output pins SDIO, DOUT, GPO1, GPO2, and GPO3.  
Rev. 1.0  
5
 
 
 
 
Si4704/05-D50  
Table 4. Reset Timing Characteristics1,2,3  
(VA = 2.7 to 5.5 V, VD = 1.62 to 3.6 V, TA = –20 to 85 °C)  
Parameter  
Symbol  
Min  
100  
30  
Typ  
Max  
Unit  
µs  
RST Pulse Width and GPO1, GPO2/INT Setup to RST  
GPO1, GPO2/INT Hold from RST  
Important Notes:  
t
SRST  
t
ns  
HRST  
1. When selecting 2-wire mode, the user must ensure that a 2-wire start condition (falling edge of SDIO while SCLK is  
high) does not occur within 300 ns before the rising edge of RST.  
2. When selecting 2-wire mode, the user must ensure that SCLK is high during the rising edge of RST, and stays high until  
after the first start condition.  
3. When selecting 3-wire mode, the user must ensure that a rising edge of SCLK does not occur within 300 ns before the  
rising edge of RST.  
4. If GPO1 and GPO2 are actively driven by the user, then minimum tSRST is only 30 ns. If GPO1 or GPO2 is high  
impedance, then minimum tSRST is 100 µs to provide time for on-chip 1 Mdevices (active while RST is low) to pull  
GPO1 high and GPO2 low.  
tSRST tHRST  
70%  
RST  
30%  
70%  
GPO1  
30%  
70%  
GPO2  
30%  
Figure 1. Reset Timing Parameters for Busmode Select Method  
6
Rev. 1.0  
 
 
Si4704/05-D50  
Table 5. 2-Wire Control Interface Characteristics1,2,3  
(VA = 2.7 to 5.5 V, VD = 1.62 to 3.6 V, TA = –20 to 85 °C)  
Parameter  
Symbol Test Condition  
Min  
0
Typ  
Max  
400  
Unit  
kHz  
µs  
SCLK Frequency  
SCLK Low Time  
SCLK High Time  
f
SCL  
t
1.3  
0.6  
0.6  
LOW  
t
µs  
HIGH  
SCLK Input to SDIO Setup  
t
t
µs  
SU:STA  
(START)  
SCLK Input to SDIO Hold  
0.6  
µs  
HD:STA  
(START)  
SDIO Input to SCLK Setup  
t
t
100  
0
900  
ns  
ns  
µs  
SU:DAT  
4, 5  
SDIO Input to SCLK Hold  
HD:DAT  
SU:STO  
SCLK Input to SDIO Setup  
t
0.6  
(STOP)  
STOP to START Time  
SDIO Output Fall Time  
t
1.3  
µs  
ns  
BUF  
t
250  
f:OUT  
Cb  
----------  
1pF  
20 + 0.1  
SDIO Input, SCLK Rise/Fall Time  
t
t
300  
ns  
f:IN  
r:IN  
Cb  
----------  
1pF  
20 + 0.1  
SCLK, SDIO Capacitive Loading  
Input Filter Pulse Suppression  
Notes:  
C
50  
50  
pF  
ns  
b
t
SP  
1. When VD = 0 V, SCLK and SDIO are low impedance.  
2. When selecting 2-wire mode, the user must ensure that a 2-wire start condition (falling edge of SDIO while SCLK is  
high) does not occur within 300 ns before the rising edge of RST.  
3. When selecting 2-wire mode, the user must ensure that SCLK is high during the rising edge of RST, and stays high  
until after the first start condition.  
4. The Si4704/05 delays SDIO by a minimum of 300 ns from the VIH threshold of SCLK to comply with the minimum  
tHD:DAT specification.  
5. The maximum tHD:DAT has only to be met when fSCL = 400 kHz. At frequencies below 400 kHz, tHD:DAT may be violated  
as long as all other timing parameters are met.  
Rev. 1.0  
7
 
 
 
 
Si4704/05-D50  
tSU:STA tHD:STA  
tLOW  
tHIGH  
tr:IN  
tf:IN  
tSP  
tSU:STO  
tBUF  
70%  
SCLK  
30%  
70%  
SDIO  
30%  
tf:IN,  
tf:OUT  
START  
tHD:DAT tSU:DAT  
tr:IN  
STOP  
START  
Figure 2. 2-Wire Control Interface Read and Write Timing Parameters  
SCLK  
SDIO  
A6-A0,  
R/W  
D7-D0  
D7-D0  
START  
ADDRESS + R/W  
ACK  
DATA  
ACK  
DATA  
ACK  
STOP  
Figure 3. 2-Wire Control Interface Read and Write Timing Diagram  
8
Rev. 1.0  
 
 
Si4704/05-D50  
Table 6. 3-Wire Control Interface Characteristics  
(V = 2.7 to 5.5 V, V = 1.62 to 3.6 V, TA = –20 to 85 °C)  
A
D
Parameter  
Symbol  
Test Condition  
Min  
0
Typ  
Max  
2.5  
Unit  
MHz  
ns  
SCLK Frequency  
SCLK High Time  
SCLK Low Time  
f
CLK  
t
25  
25  
20  
10  
10  
2
HIGH  
t
ns  
LOW  
SDIO Input, SEN to SCLK Setup  
SDIO Input to SCLK Hold  
t
ns  
S
t
ns  
HSDIO  
SEN Input to SCLK Hold  
t
ns  
HSEN  
SCLK to SDIO Output Valid  
SCLK to SDIO Output High Z  
SCLK, SEN, SDIO, Rise/Fall Time  
t
Read  
Read  
25  
25  
10  
ns  
CDV  
t
2
ns  
CDZ  
t , t  
ns  
R
F
70%  
SCLK  
30%  
tR  
tF  
tHSDIO  
tHIGH  
tLOW  
tHSEN  
tS  
70%  
tS  
SEN  
30%  
A6-A5,  
R/W,  
A4-A1  
70%  
A7  
A0  
D15  
D14-D1  
D0  
SDIO  
30%  
Address In  
Data In  
Figure 4. 3-Wire Control Interface Write Timing Parameters  
70%  
30%  
SCLK  
SEN  
tHSDIO  
tCDV  
tHSEN  
tS  
tCDZ  
70%  
30%  
tS  
70%  
30%  
A6-A5,  
R/W,  
A4-A1  
A7  
A0  
D15  
D14-D1  
D0  
SDIO  
½ Cycle Bus  
Turnaround  
Address In  
Data Out  
Figure 5. 3-Wire Control Interface Read Timing Parameters  
Rev. 1.0  
9
 
 
 
Si4704/05-D50  
Table 7. Digital Audio Interface Characteristics  
(V = 2.7 to 5.5 V, V = 1.62 to 3.6 V, TA = –20 to 85 °C)  
A
D
Parameter  
Symbol Test Condition  
Min  
26  
10  
10  
5
Typ  
Max  
1000  
Unit  
ns  
DCLK Cycle Time  
t
DCT  
DCH  
DCLK Pulse Width High  
t
ns  
DCLK Pulse Width Low  
t
ns  
DCL  
DFS Setup Time to DCLK Rising Edge  
DFS Hold Time from DCLK Rising Edge  
t
ns  
SU:DFS  
HD:DFS  
t
5
ns  
DOUT Propagation Delay from DCLK Falling  
Edge  
t
0
12  
ns  
PD:DOUT  
tDCH  
tDCL  
DCLK  
tDCT  
DFS  
tHD:DFS  
tSU:DFS  
DOUT  
tPD:OUT  
Figure 6. Digital Audio Interface Timing Parameters, I2S Mode  
10  
Rev. 1.0  
Si4704/05-D50  
Table 8. FM Receiver Characteristics1,2  
(V = 2.7 to 5.5 V, V = 1.62 to 3.6 V, TA = –20 to 85 °C, 76–108 MHz)  
A
D
Parameter  
Symbol  
Test Condition  
Min  
76  
Typ  
Max  
108  
3.5  
Unit  
MHz  
Input Frequency  
f
RF  
3,4,5  
Sensitivity  
(S+N)/N = 26 dB  
2.2  
11  
µV EMF  
µV EMF  
6
RDS Sensitivity  
f = 2 kHz,  
RDS BLER < 5%  
6,7  
6,7  
LNA Input Resistance  
3
4
4
5
5
6
k  
LNA Input Capacitance  
pF  
6,8  
Input IP3  
100  
40  
35  
60  
35  
72  
15  
35  
55  
70  
45  
105  
50  
50  
70  
90  
1
dBµV EMF  
3,4,6,7  
m = 0.3  
±200 kHz  
±400 kHz  
In-band  
dB  
dB  
dB  
dB  
AM Suppression  
Adjacent Channel Selectivity  
Alternate Channel Selectivity  
Spurious Response Rejection  
6
3,4,7  
80  
mV  
Audio Output Voltage  
RMS  
3,7,9  
dB  
Hz  
Audio Output L/R Imbalance  
Audio Frequency Response Low  
6
–3 dB  
–3 dB  
30  
0.5  
80  
54  
6
kHz  
dB  
Audio Frequency Response High  
7,9  
42  
63  
58  
0.1  
75  
50  
34  
30  
Audio Stereo Separation  
3,4,5,7  
dB  
Audio Mono S/N  
4,5,6,7  
dB  
Audio Stereo S/N  
3,7,9  
%
Audio THD  
6
De-emphasis Time Constant  
FM_DEEMPHASIS = 2  
FM_DEEMPHASIS = 1  
f = ±400 kHz  
µs  
µs  
3,4,5,6,12,13  
Blocking Sensitivity  
dBµV  
dBµV  
f = ±4 MHz  
Notes:  
1. Additional testing information is available in “AN388: Si470x/1x/2x/3x/4x Evaluation Board Test 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  
= 1 kHz, 75 µs de-emphasis, MONO = enabled, and L = R unless noted otherwise.  
MOD  
4. f = 22.5 kHz.  
5. B = 300 Hz to 15 kHz, A-weighted.  
AF  
6. Guaranteed by characterization.  
7. V  
= 1 mV.  
EMF  
8. |f – f | > 2 MHz, f = 2 x f – f . AGC is disabled.  
2
1
0
1
2
9. f = 75 kHz.  
10. At L and R  
pins.  
OUT  
OUT  
11. Analog audio output mode.  
12. Blocker Amplitude = 100 dBµV  
13. Sensitivity measured at (S+N)/N = 26 dB.  
14. At temperature (25°C).  
Rev. 1.0  
11  
 
 
 
 
 
 
 
 
Si4704/05-D50  
Table 8. FM Receiver Characteristics1,2 (Continued)  
(V = 2.7 to 5.5 V, V = 1.62 to 3.6 V, TA = –20 to 85 °C, 76–108 MHz)  
A
D
Parameter  
Symbol  
Test Condition  
f = ±400 kHz, ±800 kHz  
f = ±4 MHz, ±8 MHz  
Single-ended  
Min  
Typ  
40  
35  
Max  
Unit  
dBµV  
dBµV  
k  
3,4,5,6,12,13  
Intermod Sensitivity  
6,10  
R
10  
Audio Output Load Resistance  
L
6,10  
C
Single-ended  
50  
60  
pF  
Audio Output Load Capacitance  
L
6
Seek/Tune Time  
RCLK tolerance  
= 100 ppm  
ms/channel  
6
Powerup Time  
From powerdown  
110  
3
ms  
dB  
14  
RSSI Offset  
Input levels of 8 and  
60 dBµV at RF Input  
–3  
Notes:  
1. Additional testing information is available in “AN388: Si470x/1x/2x/3x/4x Evaluation Board Test 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  
= 1 kHz, 75 µs de-emphasis, MONO = enabled, and L = R unless noted otherwise.  
MOD  
4. f = 22.5 kHz.  
5. B = 300 Hz to 15 kHz, A-weighted.  
AF  
6. Guaranteed by characterization.  
7. V  
= 1 mV.  
EMF  
8. |f – f | > 2 MHz, f = 2 x f – f . AGC is disabled.  
2
1
0
1
2
9. f = 75 kHz.  
10. At L and R  
pins.  
OUT  
OUT  
11. Analog audio output mode.  
12. Blocker Amplitude = 100 dBµV  
13. Sensitivity measured at (S+N)/N = 26 dB.  
14. At temperature (25°C).  
12  
Rev. 1.0  
Si4704/05-D50  
Table 9. 64–75.9 MHz Input Frequency FM Receiver Characteristics1,2,6  
(V = 2.7 to 5.5 V, V = 1.62 to 3.6 V, TA = –20 to 85 °C)  
A
D
Parameter  
Symbol  
Test Condition  
Min  
64  
3
Typ  
Max  
75.9  
5
Unit  
MHz  
µV EMF  
k  
Input Frequency  
f
RF  
3,4,5  
Sensitivity  
(S+N)/N = 26 dB  
3.5  
4
7
LNA Input Resistance  
7
LNA Input Capacitance  
4
5
6
pF  
8
Input IP3  
72  
15  
70  
45  
10  
105  
50  
50  
70  
80  
90  
1
dBµV EMF  
dB  
3,4,7  
m = 0.3  
±200 kHz  
±400 kHz  
AM Suppression  
dB  
Adjacent Channel Selectivity  
Alternate Channel Selectivity  
dB  
3,4,7  
mV  
Audio Output Voltage  
RMS  
3,7,9  
dB  
Audio Output L/R Imbalance  
–3 dB  
–3 dB  
30  
80  
54  
50  
60  
Hz  
Audio Frequency Response Low  
Audio Frequency Response High  
kHz  
3,4,5,7,10  
63  
0.1  
75  
50  
dB  
Audio Mono S/N  
3,7,9  
%
Audio THD  
De-emphasis Time Constant  
FM_DEEMPHASIS = 2  
FM_DEEMPHASIS = 1  
Single-ended  
µs  
µs  
k  
10  
R
Audio Output Load Resistance  
L
L
10  
C
Single-ended  
pF  
Audio Output Load Capacitance  
Seek/Tune Time  
RCLK tolerance  
= 100 ppm  
ms/channel  
Powerup Time  
From powerdown  
110  
3
ms  
dB  
11  
RSSI Offset  
Input levels of 8 and  
60 dBµV EMF  
–3  
Notes:  
1. Additional testing information is available in “AN388: Si470x/1x/2x/3x/4x Evaluation Board Test 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  
= 1 kHz, 75 µs de-emphasis, MONO = enabled, and L = R unless noted otherwise.  
MOD  
4. f = 22.5 kHz.  
5. B = 300 Hz to 15 kHz, A-weighted.  
AF  
6. Guaranteed by characterization.  
7. V  
= 1 mV.  
EMF  
8. |f – f | > 2 MHz, f = 2 x f – f . AGC is disabled.  
2
1
0
1
2
9. f = 75 kHz.  
10. At L and R  
pins.  
OUT  
OUT  
11. At temperature (25 °C).  
Rev. 1.0  
13  
 
 
 
 
 
 
 
 
 
Si4704/05-D50  
Table 10. Reference Clock and Crystal Characteristics  
(V = 2.7 to 5.5 V, V = 1.62 to 3.6 V, TA = –20 to 85 °C)  
A
D
Parameter  
Symbol  
Test Condition  
Min  
Typ  
Max  
Unit  
Reference Clock  
1,2  
RCLK Supported Frequencies  
31.130 32.768 40,000  
kHz  
1,3  
RCLK Frequency Tolerance  
–100  
1
100  
ppm  
1,2  
REFCLK_PRESCALE  
4095  
1
REFCLK  
31.130 32.768 34.406  
kHz  
Crystal Oscillator  
1
Crystal Oscillator Frequency  
–100  
32.768  
kHz  
ppm  
pF  
1,3  
Crystal Frequency Tolerance  
100  
3.5  
1
Board Capacitance  
ESR  
40  
k  
C Single-ended  
12  
pF  
L
Notes:  
1. Guaranteed by characterization.  
2. The Si4704/05 divide the RCLK input by REFCLK_PRESCALE to obtain REFCLK. There are some RCLK frequencies  
between 31.130 kHz and 40 MHz that are not supported. See “AN332: Si47xx Programming Guide,” Table 6 for more  
details.  
3. A frequency tolerance of ±50 ppm is required for FM seek/tune using 50 kHz channel spacing.  
14  
Rev. 1.0  
 
 
 
 
Si4704/05-D50  
2. Typical Application Schematic  
Optional: Digital Audio Out  
OPMODE: 0xB0, 0xB5  
C9  
GPO1  
GPO2/INT  
R3  
R2  
R1  
GPO3/DCLK  
DFS  
DOUT  
1
15  
NC  
DOUT  
C2  
2
3
4
5
14  
FM Antenna  
FMI  
LOUT  
LOUT  
ROUT  
13  
RFGND  
ROUT  
12  
Embedded Antenna  
Si4704/05  
LPI  
GND  
2.7 to 5.5 V  
C1  
D50  
11  
RSTB  
VA  
VA  
1.62 to 3.6 V  
C4  
VD  
RSTB  
RCLK  
SDIO  
SCLK  
SENB  
GPO3  
RCLK  
X1  
C6  
C5  
Optional: For Crystal OSC  
Notes:  
1. Place C1 close to V pin.  
A
2. Pins 1 and 20 are no connects, leave floating.  
3. Place C4 close to DFS pin.  
4. 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.  
5. Pin 2 or Pin 4 connects to the FM antenna interface. Pin 2 is for a half-wave antenna. Pin 4 is for an embedded antenna.  
6. Place Si4704/05 as close as possible to antenna jack and keep the FMI and LPI traces as short as possible.  
Rev. 1.0  
15  
 
Si4704/05-D50  
3. Bill of Materials  
Table 11. Si4704/05-D50 Bill of Materials  
Value/Description  
Component(s)  
Supplier  
Murata  
C1  
C2  
C4  
U1  
R1  
Supply bypass capacitor, 22 nF, ±20%, Z5U/X7R  
Coupling capacitor, 1 nF, ±20%, Z5U/X7R  
Murata  
Supply bypass capacitor, 100 nF, 10%, Z5U/X7R  
Si4704/05 FM Radio Tuner  
Murata  
Silicon Laboratories  
Venkel  
Resistor, 600   
(Optional for digital audio)  
R2  
R3  
Resistor, 2 k  
(Optional for digital audio)  
Venkel  
Venkel  
Venkel  
Murata  
Epson  
Resistor, 2 k  
(Optional for digital audio)  
C5, C6  
C9  
Crystal load capacitors, 22 pF, ±5%, COG  
(Optional for crystal oscillator option)  
Noise mitigating capacitor, 2~5 pF  
(Optional for digital audio)  
X1  
32.768 kHz crystal  
(Optional for crystal oscillator option)  
16  
Rev. 1.0  
 
Si4704/05-D50  
4. Functional Description  
4.1. Overview  
FM Antenna  
FMI  
Si4704/05  
ADC  
ADC  
DAC  
LOUT  
LNA  
PGA  
DSP  
RFGND  
DAC  
ROUT  
AGC  
GPO  
LPI  
0/90  
DCLK  
DOUT  
DFS  
RDS  
(Si4705)  
32.768 kHz  
(TYP)  
RCLK  
RSSI  
AFC  
REG  
CONTROL  
INTERFACE  
VA  
2.7–5.5 V  
XTAL  
OSC  
Figure 7. Functional Block Diagram  
The Si4704/05-D50 offers advanced audio processing The Si4704/05 receiver draws on Silicon Laboratories’  
plus advanced RDS processing in a very small, 100% broadcast audio expertise and patent portfolio, using a  
CMOS receiver integrated circuit. The device provides digital low intermediate frequency (low-IF) receiver  
both analog and digital audio out, and a highly flexible architecture proven by hundreds of millions of Silicon  
RDS pre-processor and 100 block RDS buffer. It is an Laboratories’ broadcast audio receivers shipped  
ideal product for handsets and portable devices seeking worldwide.  
to optimize both sound and data receiver performance.  
Silicon Labs has shipped 1/2 billion broadcast audio  
For sound, the advanced audio processing is  
receivers worldwide using this architecture. The low-IF  
unprecedented in portable devices. For RDS data  
architecture allows the Si4704/05 to deliver superior  
applications such as song-tagging, meta-data, traffic  
performance while integrating the great majority of  
message channel, or other open data applications, the  
external components required by competing solutions.  
advanced and patented R(B)DS decoding engine offers  
The Si4704/05 digital integration reduces the required  
outstanding data synchronization and integrity. The  
external components of traditional offerings, resulting in  
RDS engine includes demodulation, symbol decoding,  
a solution requiring only an external bypass capacitor  
2
advanced error correction, detailed visibility to block-  
and occupying board space of approximately 15 mm .  
error rates (BLER), advanced decoder reliability, and  
The Si4704/05 is the first FM radio receiver IC to  
synchronization status. The Si4704/05 provides  
support embedded antenna technology, allowing the FM  
complete, decoded and error-corrected RDS groups  
antenna to be integrated into the enclosure or PCB of a  
(100 blocks), up to 25 groups at a time. The Si4704/05  
portable device. Refer to “AN383: Si47xx Antenna,  
offers several modes of operation for various  
Schematic, Layout, And Design Guidelines” for antenna  
applications which require more or less visibility to the  
design guidelines.  
RDS status and group data.  
The Si4704/05 is feature-rich, providing highly  
automated performance with default settings and  
extensive programmability and flexibility for customized  
system performance.  
*Note: The term “RDS” will be used to mean “RDS/RBDS”  
throughout the document.  
Rev. 1.0  
17  
Si4704/05-D50  
The Si4704/05 performs much of the FM demodulation 4.3.1. Stereo Decoder  
digitally to achieve high fidelity, optimal performance  
The Si4704/05 integrated stereo decoder automatically  
versus power consumption, and flexibility of design. The  
on-board DSP provides unmatched pilot rejection,  
selectivity, and optimum sound quality. The integrated  
micro-controller offers both the manufacturer and the  
end-user unmatched programmability and flexibility in  
the listening experience.  
decodes the MPX signal using DSP techniques. The 0  
to 15 kHz (L+R) signal is the mono output of the FM  
tuner. Stereo is generated from the (L+R), (L–R), and a  
19 kHz pilot tone. The pilot tone is used as a reference  
to recover the (L–R) signal. Output left and right  
channels are obtained by adding and subtracting the  
(L+R) and (L–R) signals, respectively.  
4.2. FM Receiver  
4.3.2. Stereo-Mono Blending  
The Si4704/05 FM receiver is based on the proven  
Si4700/01/02/03/04/05 FM radio receiver. The part  
leverages Silicon Laboratories' proven and patented FM  
broadcast radio receiver digital architecture, delivering  
excellent RF performance and interference rejection.  
The proven digital techniques provide good sensitivity in  
weak signal environments while allowing superb  
selectivity and inter-modulation immunity in strong signal  
environments.  
Adaptive noise suppression is employed to gradually  
combine the stereo left and right audio channels to a  
mono (L+R) audio signal as the signal quality degrades  
to maintain optimum sound fidelity under varying  
reception conditions. Three metrics, received signal  
strength indicator (RSSI), signal-to-noise ratio (SNR),  
and  
multipath  
interference,  
are  
monitored  
simultaneously in forcing a blend from stereo to mono.  
The metric which reflects the minimum signal quality  
takes precedence and the signal is blended  
appropriately.  
The part supports the worldwide FM broadcast band (64  
to 108 MHz) with channel spacings of 50–200 kHz. The  
low-IF architecture utilizes a single converter stage and  
digitizes the signal using a high-resolution analog-to-  
digital converter. The audio output can be directed  
either to an external headphone amplifier via analog  
in/out or to other system ICs through digital audio  
All three metrics have programmable stereo/mono  
thresholds and attack/release rates detailed in “AN332:  
Si47xx Programming Guide.” If a metric falls below its  
mono threshold, the signal is blended from stereo to full  
mono. If all metrics are above their respective stereo  
thresholds, then no action is taken to blend the signal. If  
a metric falls between its mono and stereo thresholds,  
then the signal is blended to the level proportional to the  
metric’s value between its mono and stereo thresholds,  
with an associated attack and release rate.  
Stereo/mono status can be monitored with the  
FM_RSQ_STATUS command.  
2
interface (I S) (Si4705 only).  
4.3. Stereo Audio Processing  
The output of the FM demodulator is a stereo  
multiplexed (MPX) signal. The MPX standard was  
developed in 1961, and is used worldwide. Today's  
MPX signal format consists of left + right (L+R) audio,  
left – right (L–R) audio, a 19 kHz pilot tone, and  
RDS/RBDS data as shown in Figure 8.  
4.4. Received Signal Qualifiers  
The quality of a tuned signal can vary depending on  
many factors including environmental conditions, time of  
day, and position of the antenna. To adequately manage  
the audio output and avoid unpleasant audible effects to  
the end-user, the Si4704/05-D50 monitors and provides  
indicators of the signal quality, allowing the host  
processor to perform additional processing if required  
by the customer. The Si4704/05-D50 monitors signal  
quality metrics including RSSI, SNR, and multipath  
interference on FM signals. These metrics are used to  
optimize signal processing and are also reported to the  
host processor. The signal processing algorithms can  
Mono Audio  
Left + Right  
Stereo  
Pilot  
Stereo Audio  
Left - Right  
RDS/  
RBDS  
0
15 19 23  
38  
53 57  
Frequency (kHz)  
Figure 8. MPX Signal Spectrum  
use  
either  
Silicon  
Labs'  
optimized  
settings  
(recommended) or be customized to modify  
performance.  
18  
Rev. 1.0  
 
Si4704/05-D50  
4.5. De-emphasis  
4.10. Tuning  
Pre-emphasis and de-emphasis is a technique used by The frequency synthesizer uses Silicon Laboratories’  
FM broadcasters to improve the signal-to-noise ratio of proven technology, including a completely integrated  
FM receivers by reducing the effects of high-frequency VCO. The frequency synthesizer generates the  
interference and noise. When the FM signal is quadrature local oscillator signal used to downconvert  
transmitted,  
a
pre-emphasis filter is applied to the RF input to a low intermediate frequency. The VCO  
accentuate the high audio frequencies. The Si4704/05 frequency is locked to the reference clock and adjusted  
incorporates a de-emphasis filter that attenuates high with an automatic frequency control (AFC) servo loop  
frequencies to restore a flat frequency response. Two during reception. The tuning frequency can be directly  
time constants are used in various regions. The de- programmed using the FM_TUNE_FREQ. The  
emphasis time constant is programmable to 50 or 75 µs Si4704/05 supports channel spacing of 50, 100, or  
and is set by the FM_DEEMPHASIS property.  
200 kHz in FM mode.  
4.6. Volume Control  
4.11. Seek  
The audio output may be muted. Volume is adjusted The Si4704/05 seek functionality is performed  
digitally by the RX_VOLUME property.  
completely on-chip and will search up or down the  
selected frequency band for a valid channel. A valid  
4.7. Stereo DAC  
channel is qualified according to  
a
series of  
High-fidelity stereo digital-to-analog converters (DACs) programmable signal indicators and thresholds. The  
drive analog audio signals onto the LOUT and ROUT seek function can be made to stop at the band edge and  
pins. The audio output may be muted. Volume is provide an interrupt, or wrap the band and continue  
adjusted digitally with the RX_VOLUME property.  
seeking until arriving at the original departure frequency.  
The device sets interrupts with found valid stations or, if  
the seek results in zero found valid stations, the device  
4.8. Soft Mute  
The soft mute feature is available to attenuate the audio indicates failure and again sets an interrupt.(Refer to  
outputs and minimize audible noise in very weak signal “AN332: Si47xx Programming Guide”.  
conditions. The soft mute feature is triggered by the  
SNR metric. The SNR threshold for activating soft mute  
is programmable, as are soft mute attenuation levels  
and attack and release rates.  
The Si4704/05-D50 uses RSSI, SNR, and AFC to  
qualify stations. Most of these variables have  
programmable thresholds for modifying the seek  
function according to customer needs.  
RSSI is employed first to screen all possible candidate  
stations. SNR and AFC are subsequently used in  
screening the RSSI qualified stations. The more  
thresholds the system engages, the higher the  
confidence that any found stations will indeed be valid  
broadcast stations. The Si4704/05-D50 defaults set  
RSSI to a mid-level threshold and add an SNR  
threshold set to a level delivering acceptable audio  
performance. This trade-off will eliminate very low RSSI  
stations while keeping the seek time to acceptable  
levels. Generally, the time to auto-scan and store valid  
channels for an entire FM band with all thresholds  
engaged is very short depending on the band content.  
4.9. FM Hi-Cut Control  
Hi-cut control is employed on audio outputs with  
degradation of the signal due to low SNR and/or  
multipath interference. Two metrics, SNR and multipath  
interference, are monitored concurrently in forcing hi-cut  
of the audio outputs. Programmable minimum and  
maximum thresholds are available for both metrics. The  
transition frequency for hi-cut is also programmable with  
up to seven hi-cut filter settings. A single set of attack  
and release rates for hi-cut are programmable for both  
metrics from a range of 2 ms to 64 s. The level of hi-cut  
applied can be monitored with the FM_RSQ_STATUS  
command. Hi-cut can be disabled by setting the hi-cut  
filter to audio bandwidth of 15 kHz.  
Seek is initiated using the FM_SEEK_START  
command. The RSSI, SNR, and AFC threshold settings  
are adjustable using properties.  
Rev. 1.0  
19  
 
Si4704/05-D50  
4.12.2. Audio Sample Rates  
4.12. Digital Audio Interface  
The device supports a number of industry-standard  
sampling rates including 32, 40, 44.1, and 48 kHz. The  
digital audio interface enables low-power operation by  
eliminating the need for redundant DACs on the audio  
baseband processor.  
The digital audio interface operates in slave mode and  
supports a variety of MSB-first audio data formats  
including I S and left-justified modes. The interface has  
2
three pins: digital data input (DIN), digital frame  
synchronization input (DFS), and  
a
digital bit  
synchronization input clock (DCLK). The Si4705  
supports a number of industry-standard sampling rates  
including 32, 40, 44.1, and 48 kHz. The digital audio  
interface enables low-power operation by eliminating  
the need for redundant DACs and ADCs on the audio  
baseband processor.  
4.12.1. Audio Data Formats  
The digital audio interface operates in slave mode and  
supports three different audio data formats:  
2
I S  
Left-Justified  
DSP Mode  
2
In I S mode, by default the MSB is captured on the  
second rising edge of DCLK following each DFS  
transition. The remaining bits of the word are sent in  
order, down to the LSB. The left channel is transferred  
first when the DFS is low, and the right channel is  
transferred when the DFS is high.  
In left-justified mode, by default the MSB is captured on  
the first rising edge of DCLK following each DFS  
transition. The remaining bits of the word are sent in  
order, down to the LSB. The left channel is transferred  
first when the DFS is high, and the right channel is  
transferred when the DFS is low.  
In DSP mode, the DFS becomes a pulse with a width of  
1DCLK period. The left channel is transferred first,  
followed right away by the right channel. There are two  
options in transferring the digital audio data in DSP  
mode: the MSB of the left channel can be transferred on  
the first rising edge of DCLK following the DFS pulse or  
on the second rising edge.  
In all audio formats, depending on the word size, DCLK  
frequency, and sample rates, there may be unused  
DCLK cycles after the LSB of each word before the next  
DFS transition and MSB of the next word. In addition, if  
preferred, the user can configure the MSB to be  
captured on the falling edge of DCLK via properties.  
The number of audio bits can be configured for 8, 16,  
20, or 24 bits.  
20  
Rev. 1.0  
Si4704/05-D50  
INVERTED  
DCLK  
(OFALL = 1)  
(OFALL = 0)  
DCLK  
DFS  
LEFT CHANNEL  
I2S  
RIGHT CHANNEL  
(OMODE = 0000)  
1 DCLK  
1 DCLK  
n-2  
DOUT  
1
2
3
n-1  
n
n-2  
n-1  
1
2
3
n
MSB  
LSB  
MSB  
LSB  
Figure 9. I2S Digital Audio Format  
INVERTED  
DCLK  
(OFALL = 1)  
(OFALL = 0)  
DCLK  
DFS  
LEFT CHANNEL  
RIGHT CHANNEL  
n-2  
Left-Justified  
(OMODE = 0110)  
DOUT  
1
2
3
n-2  
n-1  
n
n-1  
n
1
2
3
MSB  
LSB  
MSB  
LSB  
Figure 10. Left-Justified Digital Audio Format  
(OFALL = 0)  
DCLK  
DFS  
RIGHT CHANNEL  
n-2  
LEFT CHANNEL  
n-2  
DOUT  
1
2
3
2
n-1  
n
(OMODE = 1100)  
(OMODE = 1000)  
1
2
3
2
n-1  
n
(MSB at 1st rising edge)  
MSB  
LSB  
MSB  
LSB  
LEFT CHANNEL  
n-2  
1 DCLK  
RIGHT CHANNEL  
n-2  
DOUT  
1
3
n-1  
n
1
3
n-1  
n
(MSB at 2nd rising edge)  
MSB  
LSB  
MSB  
LSB  
Figure 11. DSP Digital Audio Format  
Rev. 1.0  
21  
Si4704/05-D50  
4.13. Embedded Antenna Support  
4.14. RDS Decoder (Si4705 Only)  
The Si4704/05 is the first FM receiver to support the fast The Si4705 implements an RDS processor for symbol  
decoding, block synchronization, error detection, and  
error correction.  
growing trend to integrate the FM receiver antenna into  
the device enclosure. The chip is designed with this  
function in mind from the outset, with multiple  
international patents pending, thus it is superior to many  
other options in price, board space, and performance.  
The Si4705 device is user configurable and provides an  
optional interrupt when RDS is synchronized, loses  
synchronization, and/or the user configurable RDS  
FIFO threshold has been met.  
Testing indicates that, when using Silicon Laboratories'  
patented techniques, embedded antenna performance  
can be very similar in many key metrics to a standard  
half-wavelength antenna. Refer to “AN383: Si47XX  
Antenna, Schematic, Layout, And Design Guidelines”  
for additional details on the implementation of support  
for an embedded antenna.  
The Si4705 reports RDS decoder synchronization  
status and detailed bit errors in the information word for  
each RDS block with the FM_RDS_STATUS command.  
The range of reportable block errors is 0, 1–2, 3–5, or  
6+. More than six errors indicates that the  
corresponding block information word contains six or  
more non-correctable errors or that the block checkword  
contains errors.  
Figure 12 shows a conceptual block diagram of the  
Si4704/05 architecture used to support the embedded  
antenna. The half-wavelength FM receive antenna is  
therefore optional. Host software can detect the  
presence of an external antenna and switch between  
the embedded antenna if desired.  
4.15. Reference Clock  
The Si4704/05 reference clock is programmable,  
supporting RCLK frequencies in Table 10. Refer to  
Table 3, “DC Characteristics” on page 5 for switching  
voltage levels and Table 10, “Reference Clock and  
Crystal Characteristics” on page 14 for frequency  
tolerance information.  
Half-wavelength  
Si4704/05  
antenna  
An onboard crystal oscillator is available to generate the  
32.768 kHz reference when an external crystal and load  
capacitors are provided. Refer to "2. Typical Application  
Schematic" on page 15. This mode is enabled using the  
POWER_UP command. Refer to Refer to “AN332:  
Si47xx Programming Guide”.  
FMI  
Integrated  
antenna  
LPI  
RFGND  
LNA  
AGC  
The Si4704/05 performance may be affected by data  
activity on the SDIO bus when using the integrated  
internal oscillator. SDIO activity results from polling the  
tuner for status or communicating with other devices  
that share the SDIO bus. If there is SDIO bus activity  
while the Si4704/05 is performing the seek/tune  
function, the crystal oscillator may experience jitter,  
which may result in mistunes, false stops, and/or lower  
SNR.  
Figure 12. Conceptual Block Diagram of the  
Si4704/05 Embedded Antenna Support  
For best seek/tune results, Silicon Laboratories  
recommends that all SDIO data traffic be suspended  
during Si4704/05 seek and tune operations. This is  
achieved by keeping the bus quiet for all other devices  
on the bus, and delaying tuner polling until the tune or  
seek operation is complete. The seek/tune complete  
(STC) interrupt should be used instead of polling to  
determine when a seek/tune operation is complete.  
22  
Rev. 1.0  
 
Si4704/05-D50  
For write operations, the user then sends an 8-bit data  
byte on SDIO, which is captured by the device on rising  
edges of SCLK. The Si4704/05 acknowledges each  
data byte by driving SDIO low for one cycle, on the next  
falling edge of SCLK. The user may write up to 8 data  
bytes in a single 2-wire transaction. The first byte is a  
command, and the next seven bytes are arguments.  
4.16. Control Interface  
A serial port slave interface is provided, which allows an  
external controller to send commands to the Si4704/05  
and receive responses from the device. The serial port  
can operate in two bus modes: 2-wire mode and 3-wire  
mode. The Si4704/05 selects the bus mode by sampling  
the state of the GPO1 and GPO2 pins on the rising  
edge of RST. The GPO1 pin includes an internal pull-up  
resistor, which is connected while RST is low, and the  
GPO2 pin includes an internal pull-down resistor, which  
is connected while RST is low. Therefore, it is only  
necessary for the user to actively drive pins which differ  
from these states. See Table 12.  
For read operations, after the Si4704/05 has  
acknowledged the control byte, it will drive an 8-bit data  
byte on SDIO, changing the state of SDIO on the falling  
edge of SCLK. The user acknowledges each data byte  
by driving SDIO low for one cycle, on the next falling  
edge of SCLK. If a data byte is not acknowledged, the  
transaction will end. The user may read up to 16 data  
bytes in a single 2-wire transaction. These bytes contain  
the response data from the Si4704/05.  
Table 12. Bus Mode Select on Rising Edge of  
RST  
A 2-wire transaction ends with the STOP condition,  
which occurs when SDIO rises while SCLK is high. For  
details on timing specifications and diagrams, refer to  
Table 5, “2-Wire Control Interface Characteristics” on  
page 7; Figure 2, “2-Wire Control Interface Read and  
Write Timing Parameters,” on page 8, and Figure 3, “2-  
Wire Control Interface Read and Write Timing Diagram,”  
on page 8.  
Bus Mode  
2-Wire  
GPO1  
1
GPO2  
0
0
3-Wire  
0 (must drive)  
After the rising edge of RST, the pins GPO1 and GPO2  
are used as general purpose output (O) pins as  
described in Section “4.17. GPO Outputs”. In any bus  
4.16.2. 3-Wire Control Interface Mode  
mode, commands may only be sent after V and V  
IO  
DD  
supplies are applied.  
When selecting 3-wire mode, the user must ensure that  
a rising edge of SCLK does not occur within 300 ns  
before the rising edge of RST.  
In any bus mode, before sending a command or reading  
a response, the user must first read the status byte to  
ensure that the device is ready (CTS bit is high).  
The 3-wire bus mode uses the SCLK, SDIO, and SEN_  
pins. A transaction begins when the user drives SEN  
low. Next, the user drives a 9-bit control word on SDIO,  
which is captured by the device on rising edges of  
SCLK. The control word consists of a 3-bit device  
address (A7:A5 = 101b), a read/write bit (read = 1, write  
= 0), and a 5-bit register address (A4:A0).  
4.16.1. 2-Wire Control Interface Mode  
When selecting 2-wire mode, the user must ensure that  
SCLK is high during the rising edge of RST, and stays  
high until after the first start condition. Also, a start  
condition must not occur within 300 ns before the rising  
edge of RST.  
For write operations, the control word is followed by a  
16-bit data word, which is captured by the device on  
rising edges of SCLK.  
The 2-wire bus mode uses only the SCLK and SDIO  
pins for signaling. A transaction begins with the START  
condition, which occurs when SDIO falls while SCLK is  
high. Next, the user drives an 8-bit control word serially  
on SDIO, which is captured by the device on rising  
edges of SCLK. The control word consists of a 7-bit  
device address, followed by a read/write bit (read = 1,  
write = 0). The Si4704/05 acknowledges the control  
word by driving SDIO low on the next falling edge of  
SCLK.  
For read operations, the control word is followed by a  
delay of one-half SCLK cycle for bus turn-around. Next,  
the Si4704/05 will drive the 16-bit read data word  
serially on SDIO, changing the state of SDIO on each  
rising edge of SCLK.  
A transaction ends when the user sets SEN high, then  
pulses SCLK high and low one final time. SCLK may  
either stop or continue to toggle while SEN is high.  
Although the Si4704/05 will respond to only a single  
device address, this address can be changed with the  
SEN pin (note that the SEN pin is not used for signaling  
in 2-wire mode). When SEN = 0, the 7-bit device  
address is 0010001b. When SEN = 1, the address is  
1100011b.  
In 3-wire mode, commands are sent by first writing each  
argument to register(s) 0xA1–0xA3, then writing the  
command word to register 0xA0. A response is  
retrieved by reading registers 0xA8–0xAF.  
Rev. 1.0  
23  
 
Si4704/05-D50  
For details on timing specifications and diagrams, refer  
to Table 6, “3-Wire Control Interface Characteristics” on  
page 9; Figure 4, “3-Wire Control Interface Write Timing  
Parameters,” on page 9, and Figure 5, “3-Wire Control  
Interface Read Timing Parameters,” on page 9.  
4.19. Programming with Commands  
To ease development time and offer maximum  
customization, the Si4704/05 provides a simple yet  
powerful software interface to program the receiver. The  
device is programmed using commands, arguments,  
properties, and responses. To perform an action, the  
user writes a command byte and associated arguments,  
causing the chip to execute the given command.  
Commands control an action such as powerup the  
device, shut down the device, or tune to a station.  
Arguments are specific to a given command and are  
used to modify the command. A complete list of  
commands is available in “AN332: Si47xx Programming  
Guide”.  
4.17. GPO Outputs  
The Si4704/05 provides three general-purpose output  
pins. The GPO pins can be configured to output a  
constant low, constant high, or high-Z. The GPO pins  
are multiplexed with the bus mode pins or DCLK,  
depending on the application schematic of the device.  
GPO2/INT can be configured to provide interrupts for  
seek and tune complete, receive signal quality, and  
RDS.  
Properties are a special command argument used to  
modify the default chip operation and are generally  
configured immediately after powerup. Examples of  
properties are de-emphasis level, RSSI seek threshold,  
and soft mute attenuation threshold. Responses provide  
the user information and are echoed after a command  
and associated arguments are issued. All commands  
provide a one-byte status update indicating interrupt  
and clear-to-send status information. For a detailed  
description of the commands and properties for the  
Si4704/05, see “AN332: Si47xx Programming Guide”.  
4.18. Reset, Powerup, and Powerdown  
Setting the RST pin low will disable analog and digital  
circuitry, reset the registers to their default settings, and  
disable the bus. Setting the RST pin high will bring the  
device out of reset. A powerdown mode is available to  
reduce power consumption when the part is idle. Putting  
the device in powerdown mode will disable analog and  
digital circuitry while keeping the bus active.  
24  
Rev. 1.0  
Si4704/05-D50  
5. Commands and Properties  
Refer to “AN332: Si47xx Programming Guide”.  
Rev. 1.0  
25  
Si4704/05-D50  
6. Pin Descriptions: Si4704/05-GM  
20 19 18 17  
NC  
1
16  
FMI 2  
RFGND 3  
LPI 4  
15 DOUT  
14 LOUT  
13 ROUT  
12 GND  
11 VA  
GND  
PAD  
RST 5  
6
7
8
9
10  
Pin Number(s)  
Name  
NC  
Description  
1, 20  
2
No connect. Leave floating.  
FM RF input.  
FMI  
3
RFGND  
LPI  
RF ground. Connect to ground plane on PCB.  
Loop antenna RF input.  
4
5
Device reset input (active low).  
Serial enable input (active low).  
Serial clock input.  
RST  
6
SEN  
7
SCLK  
SDIO  
RCLK  
8
Serial data input/output.  
9
External reference or crystal oscillator input.  
Digital and I/O supply voltage.  
Analog supply voltage. May be connected directly to battery.  
Right audio analog line output.  
Left audio analog line output.  
10  
11  
13  
14  
15  
16  
17  
V
D
V
A
ROUT  
LOUT  
DOUT  
DFS  
Digital audio output data.  
Digital frame synchronization.  
GPO3/DCLK General purpose output/digital bit synchronous clock or crystal oscillator  
input.  
18  
19  
General purpose output/interrupt.  
General purpose output.  
GPO2/INT  
GPO1  
12, GND PAD  
GND  
Ground. Connect to ground plane on PCB.  
26  
Rev. 1.0  
Si4704/05-D50  
7. Ordering Guide  
Part Number*  
Description  
Package  
Type  
Operating  
Temperature  
Si4704-D50-GM FM Broadcast Radio Receiver  
QFN  
Pb-free  
–20 to 85 °C  
–20 to 85 °C  
Si4705-D50-GM FM RDS Broadcast Radio Receiver  
QFN  
Pb-free  
*Note: Add an “(R)” at the end of the device part number to denote tape and reel option.  
Rev. 1.0  
27  
Si4704/05-D50  
8. Package Markings  
8.1. Si4704 Top Mark  
0450  
DTTT  
YWW  
Figure 13. Si4704 Top Mark  
8.2. Si4705 Top Mark  
0550  
DTTT  
YWW  
Figure 14. Si4705 Top Mark  
8.3. Top Mark Explanation  
Mark Method:  
YAG Laser  
Line 1 Marking:  
Part Number  
04 = Si4704  
05 = Si4705  
Firmware Revision  
R = Die Revision  
50 = Firmware Revision 5.0  
D = Revision D Die.  
Line 2 Marking:  
Line 3 Marking:  
TTT = Internal Code  
Internal tracking code.  
Circle = 0.5 mm Diameter Pin 1 Identifier.  
(Bottom-Left Justified)  
Y = Year  
Assigned by the Assembly House. Corresponds to the last  
significant digit of the year and workweek of the mold date.  
WW = Workweek  
28  
Rev. 1.0  
Si4704/05-D50  
9. Package Outline: Si4704/05  
Figure 15 illustrates the package details for the Si4704/05. Table 13 lists the values for the dimensions shown in  
the illustration.  
Figure 15. 20-pin Quad Flat No-Lead (QFN)  
Table 13. Package Dimensions  
Symbol  
Millimeters  
Nom  
Symbol  
Millimeters  
Nom  
Min  
Max  
Min  
Max  
A
A1  
b
0.50  
0.00  
0.18  
0.27  
0.55  
0.02  
0.60  
0.05  
0.30  
0.37  
f
2.53 BSC  
L
0.35  
0.00  
0.40  
0.45  
0.10  
0.05  
0.05  
0.08  
0.10  
0.10  
0.25  
L1  
c
0.32  
aaa  
bbb  
ccc  
ddd  
eee  
D
3.00 BSC  
1.70  
D2  
e
1.60  
1.80  
0.50 BSC  
3.00 BSC  
1.70  
E
E2  
1.60  
1.80  
Notes:  
1. All dimensions are shown in millimeters unless otherwise noted.  
2. Dimensioning and tolerancing per ANSI Y14.5M-1994.  
Rev. 1.0  
29  
 
 
Si4704/05-D50  
10. PCB Land Pattern: Si4704/05  
Figure 16 illustrates the PCB land pattern details for the Si4704/05-GM. Table 14 lists the values for the dimensions  
shown in the illustration.  
Figure 16. PCB Land Pattern  
30  
Rev. 1.0  
 
Si4704/05-D50  
Table 14. PCB Land Pattern Dimensions  
Symbol  
Millimeters  
Min Max  
2.71 REF  
1.60 1.80  
Symbol  
Millimeters  
Min  
Max  
D
D2  
e
GE  
W
2.10  
0.34  
0.28  
0.50 BSC  
2.71 REF  
X
E
Y
0.61 REF  
E2  
f
1.60  
2.53 BSC  
2.10  
1.80  
ZE  
ZD  
3.31  
3.31  
GD  
Notes: General  
1. All dimensions shown are in millimeters (mm) unless otherwise noted.  
2. Dimensioning and tolerancing is per the ANSI Y14.5M-1994 specification.  
3. This land pattern design is based on IPC-SM-782 guidelines.  
4. All dimensions shown are at maximum material condition (MMC). Least material  
condition (LMC) is calculated based on a fabrication allowance of 0.05 mm.  
Notes: Solder Mask Design  
1. All metal pads are to be non-solder mask defined (NSMD). Clearance between the  
solder mask and the metal pad is to be 60 µm minimum, all the way around the  
pad.  
Notes: Stencil Design  
1. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls  
should be used to assure good solder paste release.  
2. The stencil thickness should be 0.125 mm (5 mils).  
3. The ratio of stencil aperture to land pad size should be 1:1 for the perimeter pads.  
4. A 1.45 x 1.45 mm square aperture should be used for the center pad. This  
provides approximately 70% solder paste coverage on the pad, which is optimum  
to assure correct component stand-off.  
Notes: Card Assembly  
1. A No-Clean, Type-3 solder paste is recommended.  
2. The recommended card reflow profile is per the JEDEC/IPC J-STD-020  
specification for small body components.  
Rev. 1.0  
31  
Si4704/05-D50  
11. Additional Reference Resources  
Customer Support Site:  
This site contains all application notes, evaluation board schematics and layouts, and evaluation software. NDA  
is required for complete access. Please visit the Silicon Labs Technical Support web page:  
https://www.silabs.com/support/pages/contacttechnicalsupport.aspx and register to submit a technical support  
request.  
AN332: Si47xx Programming Guide  
AN342: Quick Start Guide  
AN383: Si47xx Antenna, Schematic, Layout and Design Guidelines  
AN388: Si470x/1x/2x/3x/4x Evaluation Board Test Procedure  
Si47xx EVB User’s Guide  
32  
Rev. 1.0  
Si4704/05-D50  
DOCUMENT CHANGE LIST:  
Revision 0.2 to Revision 1.0  
Updated functional block diagram  
Updated specification tables, removed TBDs  
Updated “2. Typical Application Schematic”  
Updated“3. Bill of Materials”  
Added support for FM for 64–75.9 MHz frequency  
range  
Added Section “4.6. Volume Control”  
Digital audio output now available in Si4704-D50  
Removed references to "AN344: Si4706/07/4x  
Programming Guide"  
Rev. 1.0  
33  
Smart.  
Connected.  
Energy-Friendly  
Products  
www.silabs.com/products  
Quality  
www.silabs.com/quality  
Support and Community  
community.silabs.com  
Disclaimer  
Silicon Laboratories intends to provide customers with the latest, accurate, and in-depth documentation of all peripherals and modules available for system and software implementers  
using or intending to use the Silicon Laboratories products. Characterization data, available modules and peripherals, memory sizes and memory addresses refer to each specific  
device, and "Typical" parameters provided can and do vary in different applications. Application examples described herein are for illustrative purposes only. Silicon Laboratories  
reserves the right to make changes without further notice and limitation to product information, specifications, and descriptions herein, and does not give warranties as to the accuracy  
or completeness of the included information. Silicon Laboratories shall have no liability for the consequences of use of the information supplied herein. This document does not imply  
or express copyright licenses granted hereunder to design or fabricate any integrated circuits. The products must not be used within any Life Support System without the specific  
written consent of Silicon Laboratories. A "Life Support System" is any product or system intended to support or sustain life and/or health, which, if it fails, can be reasonably expected  
to result in significant personal injury or death. Silicon Laboratories products are generally not intended for military applications. Silicon Laboratories products shall under no  
circumstances be used in weapons of mass destruction including (but not limited to) nuclear, biological or chemical weapons, or missiles capable of delivering such weapons.  
Trademark Information  
Silicon Laboratories Inc., Silicon Laboratories, Silicon Labs, SiLabs and the Silicon Labs logo, CMEMS®, EFM, EFM32, EFR, Energy Micro, Energy Micro logo and combinations  
thereof, "the world’s most energy friendly microcontrollers", Ember®, EZLink®, EZMac®, EZRadio®, EZRadioPRO®, DSPLL®, ISOmodem ®, Precision32®, ProSLIC®, SiPHY®,  
USBXpress® and others are trademarks or registered trademarks of Silicon Laboratories Inc. ARM, CORTEX, Cortex-M3 and THUMB are trademarks or registered trademarks of  
ARM Holdings. Keil is a registered trademark of ARM Limited. All other products or brand names mentioned herein are trademarks of their respective holders.  
Silicon Laboratories Inc.  
400 West Cesar Chavez  
Austin, TX 78701  
USA  
http://www.silabs.com  

相关型号:

SI4704-D60

BROADCAST FM RADIO RECEIVER WITH RDS/RBDS
SILICON

SI4704-D60-GM

Audio Single Chip Receiver, FM, CMOS, QFN-20
SILICON

SI4704-D60-GU

Audio Single Chip Receiver, FM, CMOS, QFN-20
SILICON

Si4704-D60-GU2

BROADCAST FM RADIO RECEIVER WITH RDS/RBDS
SILICON

SI4704-D60-GUR

Audio Single Chip Receiver, FM, CMOS, QFN-20
SILICON

SI4704DY

Load Switch with Level-Shift
VISHAY

SI4704DY-E3

Peripheral Driver, 1 Driver, PDSO8
VISHAY

SI4704DY-T1

Peripheral Driver, 1 Driver, PDSO8
VISHAY

SI4704DY-T1-E3

Peripheral Driver, 1 Driver, PDSO8
VISHAY

SI4705

Worldwide FM band support (64-108 MHz) integrated antenna support EN55020 compliant
SILICON

SI4705-C40

Worldwide FM band support (64-108 MHz) integrated antenna support EN55020 compliant
SILICON

SI4705-C40-GM

Audio Single Chip Receiver, 3 X 3 MM, ROHS COMPLIANT, QFN-20
SILICON