Si4827-A10 Broadcast Analog Tuning Digital Display AM/FM/SW Radio Receiver

Si 4 8 2 7 - A10
B ROADCAST A N A L O G TUNING D IGITAL D ISPLAY
AM/FM/SW R ADIO R ECEIVER
Features

Worldwide FM band support

(64–109 MHz)
Worldwide AM band support

(504–1750 kHz)

SW band support (2.3–28.5 MHz)
Selectable support for all AM/FM/SW 
regional bands

Enhanced FM/SW band coverage
2-wire control interface

Mono output


Valid station indicator

Digital volume support
Bass/Treble support







Minimal BOM components with no
manual alignment
Excellent real-world performance
China TV channels audio carrier
reception in FM band
2.0 to 3.6 V supply voltage
Wide range of ferrite loop sticks and
air loop antenna support
16-pin SOIC package
RoHS compliant
 Not EN55020 compliant *
*Note: For consumer applications that
require EN 55020 compliance, use
Si4844-B.
Ordering Information:
See page 19.
Pin Assignments
Applications
Si4827-A10 (SOIC)
Table and portable radios
 Boom boxes
 Clock radios
Modules for consumer electronics
 Toys, lamps, and any application
needing an AM/FM/SW radio


Description
1
16
AOUT
2
15
GND
3
14
VDD
4
13
XTALI
NC
5
12
XTALO/LNA_EN
FMI
6
11
SCLK
RFGND
7
10
SDIO
8
9
RST
IRQ
TUNE1
TUNE2
BAND
The Si4827 is an entry level analog-tuned digital-display digital CMOS AM/FM/SW
radio receiver IC that integrates the complete receiver function from antenna input
to audio output. Working with Host MCU (I2C-compatible 2-wire control interface),
frequencies information can be displayed on LCD while the analog-tune features
are kept. The Si4827 enhances the FM and SW band coverage, and further
supports China TV channels audio reception in FM band. The superior control
algorithm integrated in the Si4827 provides an easy and reliable control interface
while eliminating all the manual tuned external components used in traditional
solutions.
Functional Block Diagram
Si4827
Si4830/34
ADC
AMI
AM
ANT
RFGND
LNA
DSP
DAC
AMI
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.
AOUT
ADC
FM
ANT
AGC
FMI
0/90
TUNE1/2
ADC
CONTROL INTERFACE
BAND
XTAL
OSC
IRQ
REG
Rev. 1.0 5/13
RST
VDD
SDIO
2.0~3.6V
AFC
SCLK
XTALI
Copyright © 2013 by Silicon Laboratories
Si4827-A10
Si4827-A10
2
Rev. 1.0
Si4827-A10
TABLE O F C ONTENTS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2. FM Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
4.3. AM Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
4.4. SW Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.5. Frequency Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.6. Band Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
4.7. Bass and Treble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
4.8. Volume Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.9. High Fidelity DAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.10. Soft Mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.11. Reference Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.12. Reset, Powerup, and Powerdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.13. Memorizing Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.14. Programming with Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5. Commands and Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6. Pin Descriptions: Si4827-A10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8. Package Outline: Si4827-A10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
9. PCB Land Pattern: Si4827-A10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
10. Top Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
10.1. Si4827-A10 Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
10.2. Top Marking Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
11. Additional Reference Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Rev. 1.0
3
Si4827-A10
1. Electrical Specifications
Table 1. Recommended Operating Conditions1,2
Parameter
Supply Voltage
Symbol
3
Power Supply Powerup Rise Time
Ambient Temperature Range
Test Condition
Min
Typ
Max
Unit
VDD
2.0
—
3.6
V
VDDRISE
10
—
—
µs
TA
0
25
70
°C
Notes:
1. Typical values in the data sheet apply at VDD = 3.3 V and 25 °C unless otherwise stated.
2. All minimum and maximum specifications in the data sheet apply across the recommended operating conditions for
minimum VDD = 2.7 V.
3. Operation at minimum VDD is guaranteed by characterization when VDD voltage is ramped down to 2.0 V. Part
initialization may become unresponsive below 2.3 V.
Table 2. DC Characteristics
(VDD = 2.7 to 3.6 V, TA = 0 to 70 °C)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
IFM
—
21.0
—
mA
IAM
—
20.0
—
mA
IDDPD
—
10
—
µA
FM Mode
Supply Current*
AM/SW Mode
Supply Current*
Supplies and Interface
VDD Powerdown
Current
*Note: Specifications are guaranteed by characterization.
4
Rev. 1.0
Si4827-A10
Table 3. Reset Timing Characteristics
(VDD = 2.7 to 3.6 V, TA = 0 to 70 °C)
Parameter
Symbol
Min
Typ
Max
Unit
RSTB Pulse Width
tPRST
100
—
—
µs
2-wire Bus Idle Time After RSTB Rises
tSDIO
100
—
—
µs
2-wire Bus Idle Time Before RSTB Rises, and VDD Valid
Time Before RSTB Rises
tSRST
100
—
—
µs
RSTB Low Time Before VDD Becomes Invalid
tRRST
0
—
—
µs
Notes:
1. RSTB must be held low for at least 100 µs after the voltage supply has been ramped up.
2. RSTB needs to be asserted (pulled low) prior to the supply voltage being ramped down.
tSRST
VDD
tPRST
tSDIO
tRRST
tSDIO
RSTB
SCLK
POWER_UP
Normal
Operation
POWER_UP
Normal
Operation
SDIO
Figure 1. Reset Timing
Rev. 1.0
5
Si4827-A10
Table 4. 2-Wire Control Interface Characteristics1,2,3
(VDD = 2.7 to 3.6 V, TA = 0 to 70 °C)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
SCLK Frequency
fSCLK
0
—
400
kHz
SCLK Low Time
tLOW
1.3
—
—
µs
SCLK High Time
tHIGH
0.6
—
—
µs
SCLK Input to SDIO  Setup
(START)
tSU:STA
0.6
—
—
µs
SCLK Input to SDIO  Hold
(START)
tHD:STA
0.6
—
—
µs
SDIO Input to SCLK  Setup
tSU:DAT
100
—
—
ns
SDIO Input to SCLK  Hold4,5
tHD:DAT
0
—
900
ns
SCLK input to SDIO  Setup
(STOP)
tSU:STO
0.6
—
—
µs
STOP to START Time
tBUF
1.3
—
—
µs
SDIO Output Fall Time
tf:OUT
—
250
ns
—
300
ns
Cb
20 + 0.1 ----------1pF
SDIO Input, SCLK Rise/Fall Time
tf:IN
tr:IN
Cb
20 + 0.1 ----------1pF
SCLK, SDIO Capacitive Loading
Cb
—
—
50
pF
Input Filter Pulse Suppression
tSP
—
—
50
ns
Notes:
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 Si4827 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 fSCLK = 400 kHz. At frequencies below 400 kHz, tHD:DAT may be
violated as long as all other timing parameters are met.
6
Rev. 1.0
Si4827-A10
SCLK
SDIO
tSU:STA tHD:STA
tLOW
START
tr:IN
tHIGH
tr:IN
tf:IN
tSP
tSU:STO
tBUF
70%
30%
70%
30%
tf:IN,
tf:OUT
tHD:DAT tSU:DAT
STOP
START
Figure 2. 2-Wire Control Interface Read and Write Timing Parameters
SCLK
A6-A0,
R/W
SDIO
START
ADDRESS + R/W
D7-D0
ACK
DATA
D7-D0
ACK
DATA
ACK
STOP
Figure 3. 2-Wire Control Interface Read and Write Timing Diagram
Rev. 1.0
7
Si4827-A10
Table 5. FM Receiver Characteristics1,2
(VDD = 2.7 to 3.6 V, TA = 0 to 70 °C)
Parameter
Min
Typ
Max
Unit
64
—
109
MHz
—
4.0
—
µV EMF
LNA Input Resistance4,5
—
4
—
k
LNA Input Capacitance4,5
—
5
—
pF
—
50
—
dB
—
105
—
dBµV EMF
Input Frequency
Symbol
fRF
Sensitivity with Headphone
Network
Test Condition
(S+N)/N = 26 dB
3
m = 0.3
AM Suppression4,5,6,7
Input IP34,8
Adjacent Channel Selectivity4
±200 kHz
—
45
—
dB
Alternate Channel Selectivity4
±400 kHz
—
60
—
dB
Audio Output Voltage5,6,7,12
—
72
—
mVRMS
Audio Mono S/N5,6,7,9,10
—
45
—
dB
Audio Frequency Response Low4
–3 dB
—
—
30
Hz
Audio Frequency Response High4
–3 dB
15
—
—
kHz
—
0.1
0.5
%
Audio THD5,6,11
Audio Output Load Resistance4,10
RL
Single-ended
10
—
—
k
Audio Output Load Capacitance4,10
CL
Single-ended
—
—
50
pF
Notes:
1. Additional testing information is available in “AN603: Si4822/26/27/40/44-DEMO 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 “AN602: Si4822/26/27/40/44 Antenna,
Schematic, Layout, and Design Guidelines.” Silicon Laboratories will evaluate schematics and layouts for qualified
customers.
3. Frequency is 64~109 MHz.
4. Guaranteed by characterization.
5. VEMF = 1 mV.
6. FMOD = 1 kHz, MONO, and L = R unless noted otherwise.
7. f = 22.5 kHz.
8. |f2 – f1| > 2 MHz, f0 = 2 x f1 – f2.
9. BAF = 300 Hz to 15 kHz, A-weighted.
10. At AOUT pin.
11. f = 75 kHz.
12. Tested in Digital Volume Mode.
8
Rev. 1.0
Si4827-A10
Table 6. AM/SW Receiver Characteristics1, 2
(VDD = 2.7 to 3.6 V, TA = 0 to 70 °C)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
fRF
Medium Wave (AM)
504
—
1750
kHz
Short Wave (SW)
2.3
—
28.5
MHz
(S+N)/N = 26 dB
—
30
—
µV EMF
Large Signal Voltage Handling5
THD < 8%
—
300
—
mVRMS
Power Supply Rejection Ratio5
∆VDD = 100 mVRMS, 100 Hz
—
40
—
dB
Audio Output Voltage3,6,8
—
54
—
mVRMS
Audio S/N3,4,6
—
45
—
dB
Audio THD3,6
—
0.1
—
%
180
—
450
µH
Input Frequency
Sensitivity3,4,5
Antenna Inductance5,7
Notes:
1. Additional testing information is available in “AN603: Si4822/26/27/40/44 DEMO Board Test Procedure.”
Volume = maximum for all tests. Tested at RF = 6 MHz.
2. To ensure proper operation and receiver performance, follow the guidelines in “AN602: Si4822/26/27/40/44 Antenna,
Schematic, Layout, and Design Guidelines.” Silicon Laboratories will evaluate schematics and layouts for qualified
customers.
3. FMOD = 1 kHz, 30% modulation, 2 kHz channel filter.
4. BAF = 300 Hz to 15 kHz, A-weighted.
5. Guaranteed by characterization.
6. VIN = 5 mVrms.
7. Stray capacitance on antenna and board must be < 10 pF to achieve full tuning range at higher inductance levels.
8. Tested in Digital Volume Mode.
Table 7. Reference Clock and Crystal Characteristics
(VDD = 2.7 to 3.6 V, TA = 0 to 70 °C)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
31.130
32.768
40,000
kHz
–100
—
100
ppm
1
—
4095
31.130
32.768
34.406
kHz
Crystal Oscillator Frequency
—
32.768
—
kHz
Crystal Frequency Tolerance
–100
—
100
ppm
—
—
3.5
pF
Reference Clock
XTALI Supported Reference Clock
Frequencies*
Reference Clock Frequency
Tolerance for XTALI
REFCLK_PRESCALE
REFCLK
Crystal Oscillator
Board Capacitance
*Note: The Si4827-A10 divides 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. For more details, see Table 9 of "AN610:
Si48xx ATDD Programming Guide.”
Rev. 1.0
9
Si4827-A10
Table 8. Thermal Conditions
Parameter
Symbol
Min
Typ
Max
Unit
Thermal Resistance*
JA
—
80
—
°C/W
Ambient Temperature
TA
0
25
70
°C
Junction Temperature
TJ
—
—
77
°C
*Note: Thermal resistance assumes a multi-layer PCB with the exposed pad soldered to a topside PCB pad.
Table 9. Absolute Maximum Ratings1,2
Parameter
Symbol
Value
Unit
VDD
–0.5 to 5.8
V
IIN
10
mA
Operating Temperature
TOP
–40 to 95
°C
Storage Temperature
TSTG
–55 to 150
°C
0.4
VPK
Supply Voltage
Input
Current3
RF Input Level4
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 Si4827-A10 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 RST, SDIO, SCLK, XTALO/LNA_EN, XTALI, BAND, TUNE2, TUNE1 and IRQ.
4. At RF input pins, FMI, and AMI.
10
Rev. 1.0
Si4827-A10
2. Typical Application Schematic
TUNE1
R1
203k 1%
TUNE1
SW
B1
2.5k/100M
FMI
R2
50k 1%
S1
VR1
100k
BAND
1
2
3
AM
ANT1
AM antenna
4
IRQ
C5
R3
180k 1%
To host MCU
2
3
4
U1
R4
67k 1%
AOUT
Optional
16
GND
15
5
1
IRQ
TUNE1
TUNE2
BAND
XTALI
VDD
14
11
RSTB
9
T1
10
RFGND
SDIO
AMI
0.47u
ANT2
13
6
NC
XTALO/LNA_EN
C5
12
FMI
SCLK
8
AMI
GND
7
FM
0.47u
AOUT
C1
0.1u
Optional: AM air loop antenna
C4
0.1u
To host MCU
RESET
SDIO
VDD
2.0 TO 3.6V
SCLK
Y1
32.768KHz
C3
22p
C2
22p
Optional
Notes:
1. Place C4 close to VDD and GND pins.
2. All grounds connect directly to GND plane on PCB.
3. Pin 5 leave floating.
4. To ensure proper operation and receiver performance, follow the guidelines in “AN602: Si4822/26/27/40/44 Antenna,
Schematic, Layout, and Design Guidelines.” Silicon Labs will evaluate the schematics and layouts for qualified
customers.
5. Pin 6 connects to the FM antenna interface and pin 8 connects to the AM antenna interface.
6. Place Si4827 as close as possible to antenna jack and keep the FMI and AMI traces as short as possible.
7. Recommend keeping the AM ferrite loop antenna at least 5 cm away from the Si4827.
8. Keep the AM ferrite loop antenna away from MCU, audio amplifier, and other circuits which have AM interference.
9. Place the transformer T1 away from any sources of interference and even away from the I/O signals of the Si4827.
Rev. 1.0
11
Si4827-A10
3. Bill of Materials
Table 10. Si4827-A10 Bill of Materials
Component(s)
Value/Description
Supplier
C1
Reset capacitor 0.1 µF, ±20%, Z5U/X7R
Murata
C4
Supply bypass capacitor, 0.1 µF, ±20%, Z5U/X7R
Murata
C5
Coupling capacitor, 0.47 µF, ±20%, Z5U/X7R
Murata
B1
Ferrite bead 2.5 k/100 MHz
Murata
Variable resistor (POT), 100 k, ±10%
Kennon
VR1
U1
ANT1
Si4827-A AM/FM/SW Analog Tune Digital Display Radio
Tuner
Ferrite stick,180–450 μH
Silicon Laboratories
Jiaxin
Optional Components
C2, C3
Y1
ANT2
12
Crystal load capacitors, 22 pF, ±5%, COG
(Optional: for crystal oscillator option)
32.768 kHz crystal (Optional: for crystal oscillator option)
Air loop antenna, 10–20 μH
Venkel
Epson or equivalent
Various
S1
Band switch
Any, depends on
customer
R1
Resistor, 203 k
Venkel
R2
Resistor, 50 k, ±1%,
Venkel
R3
Resistor, 180 k, ±1%
Venkel
R4
Resistor, 67 k, ±1%
Venkel
Rev. 1.0
Si4827-A10
4. Functional Description
Si4827
Si4830/34
ADC
AMI
AM
ANT
RFGND
LNA
DSP
DAC
AOUT
ADC
FM
ANT
FMI
AGC
0/90
TUNE1/2
ADC
BAND
XTAL
OSC
IRQ
REG
RST
VDD
SDIO
2.0~3.6V
CONTROL INTERFACE
SCLK
XTALI
AFC
Figure 4. Si4827-A10 Functional Block Diagram
4.1. Overview
The Si4827-A10 is the entry level analog-tuned digitaldisplay digital CMOS AM/FM/SW radio receiver IC that
integrates the complete receiver function from antenna
input to audio output. Working with an external MCU
with LCD/LED driver, Si4827 can output the AM/FM/SW
frequencies and band and volume information to display
on LCD/LED, while using a simple potentiometer at the
front end for analog-tune. Leveraging Silicon
Laboratories' proven and patented digital low
intermediate frequency (low-IF) receiver architecture,
the Si4827 delivers superior RF performance and
interference rejection in AM, FM and SW bands.
Additionally, the digital core provides advanced audio
conditioning for all environments, removing pops, clicks,
and loud static in variable signal conditions. The
superior control algorithm integrated in Si4827 provides
easy and reliable control interface while eliminating all
the manual tuned external components used in
traditional solutions.
Like other successful audio products from Silicon Labs,
Si4827 offers unmatched integration and PCB space
savings with minimum external components and a small
board area on a single side PCB. The high integration
and complete system production test simplifies designin, increases system quality, and improves
manufacturability. The receiver has very low power
consumption, runs off two AAA batteries, and delivers
the performance benefits of high performance digital
radio experience with digital display to the legacy
analog-tuned radio market.
The Si4827 provides good flexibility in using the chip.
The frequency range of FM/AM/SW bands, deemphasis value, AM tuning step, and AM soft mute
level/rate can be either configured by the MCU or by
using external hardware to make a selection. The
reference clock of the FM tuner can be provided by
either the crystal or by the host MCU within tolerance.
The Si4827 also has flexibility in selecting bands and
configuring band properties, enabling masked Host
MCU for multiple projects, and reducing the cost of
development. Four tuning preferences are available to
meet different tuning preference requirements.
Rev. 1.0
13
Si4827-A10
4.2. FM Receiver
4.4. SW Receiver
The Si4827-A10 integrates a low noise amplifier (LNA)
supporting the worldwide FM broadcast band (64 to
109 MHz) and the TV audio stations within the
frequency range in China area are also supported. The
FM band can also be configured to be wider range such
as 64–108 MHz in one band.
The Si4827 supports short wave band receptions from
2.3 to 28.5 MHz in 5 kHz step size increments. It can
also be configured to have wide SW band that can be
used in SW radio with 1 or 2 SW bands. The Si4827
supports extensive short wave features such as minimal
discrete components and no factory adjustments. The
Si4827 supports using the FM antenna to capture short
wave signals. Refer to “AN610: Si48xx ATDD
Programming Guide” and "AN602: Si4822/26/27/40/44
Antenna, Schematic, Layout, and Design Guidelines"
for more details.
Pre-emphasis and de-emphasis is a technique used by
FM broadcasters to improve the signal-to-noise ratio of
FM receivers by reducing the effects of high frequency
interference and noise. When the FM signal is
transmitted, a pre-emphasis filter is applied to
accentuate the high audio frequencies. All FM receivers
incorporate a de-emphasis filter which attenuates high
frequencies to restore a flat frequency response. Two
time constants are used in various regions. The deemphasis time constant can be chosen to be 50 or
75 μs. Refer to "AN602: Si4822/26/27/40/44 Antenna,
Schematic, Layout, and Design Guidelines."
4.3. AM Receiver
The highly integrated Si4827-A10 supports worldwide
AM band reception from 504 to 1750 kHz with five subbands using a digital low-IF architecture with a minimum
number of external components and no manual
alignment required. This patented architecture allows
for high-precision filtering, offering excellent selectivity
and SNR with minimum variation across the AM band.
Similar to the FM receiver, the Si4827-A10 optimizes
sensitivity and rejection of strong interferers, allowing
better reception of weak stations.
To offer maximum flexibility, the receiver supports a
wide range of ferrite loop sticks from 180–450 μH. An
air loop antenna is supported by using a transformer to
increase the effective inductance from the air loop.
Using a 1:5 turn ratio inductor, the inductance is
increased by 25 times and easily supports all typical AM
air loop antennas, which generally vary between 10 and
4.5. Frequency Tuning
A valid channel can be found by tuning the
potentiometer that is connected to the TUNE1 and
TUNE2 pin of the Si4827-A10 chip.
To offer easy tuning, the Si4827-A10 also outputs the
tuned information to the MCU with LCD/LED driver to
display. It will light up the icon on display if the RF signal
quality passes a certain threshold when tuned to a valid
station. Refer to "AN610: Si48xx ATDD Programming
Guide" for more details.
4.6. Band Select
The Si4827-A10 supports worldwide AM band with five
sub-bands, US/Europe/Japan/China FM band with five
sub-bands, and SW band with 16 sub-bands. Si4827A10 provides the flexibility to configure the band and
band properties at either the MCU side or the tuner
side, enabling masked MCU for multiple projects. For
details on band selection, refer to "AN602:
Si4822/26/27/40/44 Antenna, Schematic, Layout, and
Design Guidelines" and "AN610: Si48xx ATDD
Programming Guide".
20 μH.
A 9, 10 kHz tuning step can be chosen by the external
resistor or host MCU according to the different regions,
and AM soft mute level can be programmed by the host
MCU to have different tuning experiences. One of the
AM bands can be configured as a universal AM band
that simultaneously supports 9 kHz and 10 kHz channel
spaces for all regional AM standards. Refer to “AN610:
Si48xx ATDD Programming Guide” and "AN602:
Si4822/26/27/40/44 Antenna, Schematic, Layout, and
Design Guidelines" for more details.
14
Rev. 1.0
Si4827-A10
4.7. Bass and Treble
4.12. Reset, Powerup, and Powerdown
The Si4827-A10 supports Bass/Treble tone control for
superior sound quality. The Si4827-A10 can be set to be
default normal, or programmed by the host MCU I2Ccompatible 2-wire mode. FM has nine levels
Bass/Treble effect and AM/SW has seven levels
Bass/Treble effect. For further configuration details,
refer to "AN610: Si48xx ATDD Programming Guide".
Setting the RSTB pin low will disable analog and digital
circuitry, reset the registers to their default settings, and
disable the bus. Setting the RSTB pin high will bring the
device out of reset.
4.8. Volume Control
The Si4827-A10 not only allows users to use the
traditional PVR wheel volume control through an
external speaker amplifier, it also supports digital
volume control programmed by the host MCU. Si4827A10 can be programmed to be Bass/Treble mode only
or digital volume mode only; it can also be programmed
to have the digital volume coexist with Bass/Treble in
two modes. Refer to "AN610: Si48xx ATDD
Programming Guide" and "AN602: Si4822/26/27/40/44
Antenna, Schematic, Layout, and Design Guidelines"
for more details.
4.9. High Fidelity DAC
High-fidelity digital-to-analog converters (DACs) drive
analog audio signals onto the AOUT pin. The audio
output may be muted.
4.10. Soft Mute
The soft mute feature is available to attenuate the audio
outputs and minimize audible noise in very weak signal
conditions. Advanced algorithm is implemented to get a
better analog tuning experience. 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 decay rates.
4.11. Reference Clock
The Si4827-A10 supports RCLK input (to XTALI pin)
with the spec listed in Table 7. It can be shared with the
host MCU to save extra crystal.
An onboard crystal oscillator is available to generate the
32.768 kHz reference when an external crystal and
load capacitors are provided. Refer to "AN602:
Si4822/26/27/40/44 Antenna, Schematic, Layout, and
Design Guidelines" for more details.
Figure 1 shows typical reset, startup, and shutdown
timings for the Si4827. RSTB must be held low
(asserted) during any power supply transitions and kept
asserted as specified in Figure 1 after the power
supplies are ramped up and stable. Failure to assert
RSTB as indicated here may cause the device to
malfunction and may result in permanent device
damage.
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.
4.13. Memorizing Status
The Si4827-A10 provides the feature to memorize
status from the last power down with a simple design on
PCB, including frequency of the FM/AM/SW station.
Refer to "AN602: Si4822/26/27/40/44 Antenna,
Schematic, Layout, and Design Guidelines" for details.
4.14. Programming with Commands
To ease development time and offer maximum
customization, the Si4827 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 get the
current tuned frequency. Arguments are specific to a
given command and are used to modify the command.
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 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 1-byte status update,
indicating interrupt and clear-to-send status information.
For a detailed description of the commands and
properties for the Si4827, see "AN610: Si48xx ATDD
Programming Guide".
Rev. 1.0
15
Si4827-A10
5. Commands and Properties
Table 11. Si4827-A10 FM Receiver Command Summary
Cmd
Name
Description
0xE0
ATDD_GET_STATUS
0xE1
ATDD_POWER_UP
0xE2
ATDD_AUDIO_MODE
0x10
GET_REV
0x11
POWER_DOWN
Power down device.
0x12
SET_PROPERTY
Sets the value of a property.
0x13
GET_PROPERTY
Retrieve a property's value.
Get tune freq, band and etc., status of the device.
Power up device, band selection, and band properties setup.
Audio output mode: get/set audio mode and settings.
Returns the revision information of the device.
Note: The Si4827 has its own power up and get status commands which are different from previous si47xx tuner parts. To
differentiate, we use "ATDD_POWER_UP" and ATDD_GET_STATUS to denote the ATDD specific commands instead
of the general si47xx "POWER_UP" and "STATUS" commands.
Table 12. Si4827-A10 FM Receiver Property Summary
Prop
Name
0x0201
REFCLK_FREQ
0x0202
REFCLK_PRESCALE
0x1100
FM_DEEMPHASIS
0x1300
FM_SOFT_MUTE_RATE
0x1301
FM_SOFT_MUTE_
MAX_ATTENUATION
0x1303
FM_SOFT_MUTE_
SNR_THRESHOLD
0x4000
RX_VOLUME
0x4001
RX_HARD_MUTE
0x4002
RX_BASS_TREBLE
0x4003
RX_ACTUAL_VOLUME
Default
Sets frequency of reference clock in Hz.
The range is 31130 to 34406 Hz, or 0 to disable the AFC.
Default is 32768 Hz.
0x8000
Sets the prescaler value for RCLK input.
0x0001
Sets deemphasis time constant. Default is 75 μs.
0x0002
Sets the attack and decay rates when entering and leaving
soft mute.
0x0040
FM_SOFT_MUTE_SLOPE Configures attenuation slope during soft mute in dB attenuation per dB SNR below the soft mute SNR threshold. Default
value is 2.
0x1302
16
Description
0x0002
Sets maximum attenuation during soft mute (dB). Set to 0 to
disable soft mute. Default is 16 dB.
0x0010
Sets SNR threshold to engage soft mute. Default is 4 dB.
0x0004
Sets the output volume.
0x003F
Mutes the audio output. L and R audio outputs may be muted
independently.
0x0000
Sets the output bass/treble level.
0x0004
Read the actual output volume.
0x003F
Rev. 1.0
Si4827-A10
Table 13. Si4827-A10 AM/SW Receiver Command Summary
Cmd
Name
Description
0xE0
ATDD_GET_STATUS
0xE1
ATDD_POWER_UP
0xE2
ATDD_AUDIO_MODE
0x10
GET_REV
0x11
POWER_DOWN
Power down device.
0x12
SET_PROPERTY
Sets the value of a property.
0x13
GET_PROPERTY
Retrieve a property's value.
Get tune freq, band and etc status of the device
Power up device, band selection, and band properties setup
Audio output mode: get/set audio mode settings.
Returns the revision information of the device.
Note: The Si4827 has its own power up and get status commands which are different from previous si47xx tuner parts. To
differentiate, we use "ATDD_POWER_UP" and ATDD_GET_STATUS to denote the ATDD specific commands instead
of the general Si47xx "POWER_UP" and "STATUS" commands.
Table 14. Si4827-A10 AM/SW Receiver Property Summary
Prop
Name
0x0201
REFCLK_FREQ
0x0202
REFCLK_PRESCALE
0x4000
RX_VOLUME
0x4001
RX_HARD_MUTE
0x4002
RX_BASS_TREBLE
0x4003
RX_ACTUAL_VOLUME
0x3300
AM_SOFT_MUTE_RATE
0x3301
Description
Sets frequency of reference clock in Hz.
The range is 31130 to 34406 Hz, or 0 to disable the AFC.
Default is 32768 Hz.
0x8000
Sets the prescaler value for RCLK input.
0x0001
Sets the output volume.
0x003F
Mutes the audio output. L and R audio outputs may be muted
independently.
0x0000
Sets the output bass/treble level.
0x0003
Read the actual output volume.
0x003F
Sets the attack and decay rates when entering and leaving
soft mute.
0x0040
AM_SOFT_MUTE_SLOPE Configures attenuation slope during soft mute in dB attenuation per dB SNR below the soft mute SNR threshold.
0x3302
AM_SOFT_MUTE_
MAX_ATTENUATION
0x3303
AM_SOFT_MUTE_
SNR_THRESHOLD
Default
0x0002.,
Sets maximum attenuation during soft mute (dB). Set to 0 to
disable soft mute.
0x0010
Sets SNR threshold to engage soft mute.
0x0008
Rev. 1.0
17
Si4827-A10
6. Pin Descriptions: Si4827-A10
1
16
AOUT
2
15
GND
3
14
VDD
4
13
XTALI
NC
5
12
XTALO/LNA_EN
FMI
6
11
SCLK
RFGND
7
10
SDIO
8
9
RST
IRQ
TUNE1
TUNE2
BAND
AMI
Pin Number(s)
Name
1
IRQ
Interrupt request.
2
TUNE1
Frequency tuning.
3
TUNE2
Frequency tuning.
4
BAND
Band selection and de-emphasis selection.
5
NC
No connect. Leave floating.
6
FMI
FM RF inputs. FMI should be connected to the antenna trace.
7
RFGND
8
AMI
AM RF input. AMI should be connected to the AM antenna.
9
RST
Device reset (active low) input.
10,
SDIO
Serial data input/output.
11
SCLK
Serial clock input.
12
18
Description
RF ground. Connect to ground plane on PCB.
XTALO/LNA_EN Crystal oscillator output, enable the SW external LNA in SW mode when not
used as XTALO.
13,
XTALI
Crystal oscillator input/external reference clock input
14
VDD
Supply voltage. May be connected directly to battery.
15
GND
Ground. Connect to ground plane on PCB.
16
AOUT
Audio output.
Rev. 1.0
Si4827-A10
7. Ordering Guide
Part Number1,2
Si4827-A10-CS
Description
AM/FM/SW Broadcast Analog Tune
Digital Display Radio Receiver
Package Type
Operating
Temperature/Voltage
16L SOIC Pb-free
0 to 70 °C
2.0 to 3.6 V
Notes:
1. Add an “(R)” at the end of the device part number to denote tape and reel option. The devices will typically operate at
25 °C with degraded specifications for VDD voltage ramped down to 2.0 V.
2. The -C suffix in the part number indicates Consumer Grade product. Visit www.silabs.com to get more information on
product grade specifications.
Rev. 1.0
19
Si4827-A10
8. Package Outline: Si4827-A10
The 16-pin SOIC illustrates the package details for the Si4827-A10. Table 15 lists the values for the dimensions
shown in the illustration.
Figure 5. 16-Pin SOIC
Table 15. Package Dimensions
Dimension
A
A1
A2
b
c
D
E
E1
e
L
L2
h
θ
aaa
bbb
ccc
ddd
Min
—
0.10
1.25
0.31
0.17
Max
1.75
0.25
—
0.51
0.25
9.90 BSC
6.00 BSC
3.90 BSC
1.27 BSC
0.40
1.27
0.25 BSC
0.25
0°
0.50
8°
0.10
0.20
0.10
0.25
Notes:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
3. This drawing conforms to the JEDEC Solid State Outline MS-012, Variation AC.
4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification
for Small Body Components.
20
Rev. 1.0
Si4827-A10
9. PCB Land Pattern: Si4827-A10
Figure 6 illustrates the PCB land pattern details for the Si4827-A10-CS SOIC. Table 16 lists the values for the
dimensions shown in the illustration.
Figure 6. PCB Land Pattern
Table 16. PCB Land Pattern Dimensions
Dimension
C1
Feature
(mm)
Pad Column Spacing
5.40
E
Pad Row Pitch
1.27
X1
Pad Width
0.60
Y1
Pad Length
1.55
Notes:
1. This Land Pattern Design is based on IPC-7351 pattern SOIC127P600X165-16N
for Density Level B (Median Land Protrusion).
2. All feature sizes shown are at Maximum Material Condition (MMC) and a card
fabrication tolerance of 0.05 mm is assumed.
Rev. 1.0
21
Si4827-A10
10. Top Markings
10.1. Si4827-A10 Top Marking
10.2. Top Marking Explanation
Mark Method:
Laser
Pin 1 Mark:
Mold Dimple (Bottom-Left Corner)
Font Size:
0.71 mm (2.0 Point) Right-Justified
Line 1 Marking:
Customer Part Number
Si4827A10
Circle = 1.3 mm Diameter
“e3” Pb-Free Symbol
YY = Year
WW = Work week
Assigned by the Assembly House. Corresponds to the year
and work week of the mold date.
Line 2 Marking:
TTTTTT = Manufacturing code Manufacturing Code from the Assembly Purchase Order form.
22
Rev. 1.0
Si4827-A10
11. Additional Reference Resources
Contact your local sales representatives for more information or to obtain copies of the following references:
AN602: Si4822/26/27/40/44 Antenna, Schematic, Layout, and Design Guidelines
AN603: Si4822/26/27/40/44-DEMO Board Test Procedure
 Si4827-DEMO Board User’s Guide
 AN610: Si48xx ATDD Programming Guide


Rev. 1.0
23
Si4827-A10
DOCUMENT CHANGE LIST
Revision 0.1 to Revision 0.8









Updated "Features"
Added ambient temperature range to "Table 1.
Recommended Operating Conditions"
Updated Table 6, "AM/SW Receiver Characteristics"
Updated Table 7, "Reference Clock and Crystal
Characteristics"
Updated Section "2.Typical Application Schematic"
Updated Section “4.3. AM Receiver"
Updated Section “4.7. Bass and Treble"
Updated Section 6 "Pin Descriptions: Si4827-A10"
Updated Section “8. Package Outline: Si4827-A10”
Revision 0.8 to Revision 1.0
Updated Table 3. "Reset Timing Characteristics"
Updated "Pin Assignment"
 Inserted Section 4.12. "Reset, Powerup, and
Powerdown"


24
Rev. 1.0
Smart.
Connected.
Energy-Friendly
Products
Quality
Support and Community
www.silabs.com/products
www.silabs.com/quality
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