Si 4770/ 77- A20
H I G H - P ERFORMANCE C ONSUMER E LECTRONICS
B R O A D C AST R ADIO R ECEIVER AND H D R ADIO T UNER
Features
Digital (I2S) Zero-IF AM/FM I/Q
outputs (Si4777 only)
1.2 to 5 V power supplies
QFN 40-pin, 6x6x0.85 mm
DACREF
XTAL1
RCLK/
XTAL2
ROUT
LOUT/
MPXOUT
VA
36
35
34
33
32
31
NC/BLEND
29
DCLK
FMXIN
3
28
DFS
RFGND
4
27
DOUT
RFREG
5
26
NC/QOUT
FMO
6
25
NC/IOUT
FMI
7
24
NC/IQFS
NC
8
23
NC/IQCLK
NC
9
22
VIO2
AMI
10
21
DBYP
GND PAD
13
14
15
16
17
18
19
20
A1/INTB
NC/DCLK2
NC/DOUT2
RSTB
SDA
SCL
INTB/DFS2
VIO1
VD
Description
30
2
A0
Boom boxes
Home theater systems
1
12
NC
FMXIP
11
Audio/video receivers
Consumer electronics
37
compliant
Si4770/77-A20
GPIO2
Pb-free/RoHS
Applications
Pin Assignments
38
Ordering Information:
See page 49.
GPIO1
L/R analog and digital (I2S) audio
outputs
Digital Low-IF architecture
Frequency synthesizer with fully
integrated PLL-VCO
Fully integrated AM/FM front-end
including high performance LNA,
AGC with integrated resistor and
capacitor banks, and RF and IF
peak detectors
Integrated crystal oscillator
39
40
AM/FM hi-cut control
AM lo-cut filter
FMAGC2
FMAGC1
Worldwide FM band support
(64–108 MHz)
Worldwide AM band support
(520–1710 kHz)
AM/FM HD Radio support
(Si4777 only)
Comprehensive signal quality
metrics: RSSI, SNR, multipath
interference, frequency offset,
adjacent channel RSSI,
frequency deviation, and image
RSSI
Advanced patented RDS softdecision decoder
Advanced, patented FM channel
equalizer for multipath
interference
Dynamic AM/FM channel
bandwidth control
Programmable AM/FM soft mute
FM stereo-mono blend
FM hi-blend control
Patents pending
The Si4770/77-A20 broadcast receiver and HD Radio tuner (Si4777 only)
employs an advanced, proven digital low-IF architecture to bring
outstanding receiver performance to high-performance consumer
electronics.
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Si 4770/ 77-A 20
IQFS
IOUT
QOUT
IQCLK
FMAGC2
FMAGC1
Functional Block Diagram
Si4770/77
ADC
FMXIP
FMXIN
ADC
RFREG
LOUT/
MPXOUT
DAC
ROUT
DSP
IF PKD
RF PKD
DAC
REG
RL
FMO
FMI
LNA
DCLK
DFS
DOUT
0°/90°
RDS
RF PKD
RF PKD
INTB
RSTB
AMI
2
VIO1
SCL
A1
SDA
A0
VIO2
XTAL1
RFGND
CNTRL
ClK
Gen
XTAL2/
RCLK
LNA
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
Rev. 0.9 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • September 1, 2021
Si4770/77-A20
TA B L E
Section
OF
C ONTENTS
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Typical Application Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3. Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.2. Clocking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.3. Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.4. FM Receiver Front-End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.5. AM Receiver Front-End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.6. Received Signal Qualifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.7. Digital Audio Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
4.8. Channel Equalizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.9. Digital ZIF I/Q Interface (Si4777 Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.10. IBOC Blend Mode for HD Radio (Si4777 Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.11. Stereo Audio Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
4.12. De-emphasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.13. Analog Audio and FM MPX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
4.14. Soft Mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
4.15. AM/FM Dynamic Bandwidth Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.16. Seek and Valid Station Qualification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.17. AM Hi-Cut Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4.18. FM Hi-Cut Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4.19. FM Hi-Blend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4.20. AM Lo-Cut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5. RDS/RBDS Advanced Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6. Programming Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
7. I2C Control Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
7.1. I2C Device Address Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
7.2. I2C Standard Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
8. Reset, Powerup, and Powerdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
9. Pin Descriptions: Si4770/77-A20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
10. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
11. Package Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
12. PCB Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
13. Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
13.1. Si4770/77-A20 Top Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
13.2. Top Marking Explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
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Si 4770/ 77-A 20
1. Electrical Specifications
Table 1. Recommended Operation Conditions*
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Analog Supply Voltage
VA
—
4.5
5
5.5
V
Digital Supply Voltage
VD
—
2.7
3.3
3.6
V
VIO1
—
1.7
3.3
3.6
V
VIO2
—
1.2
3.3
3.6
V
Interface Supply Voltage
*Note: All minimum and maximum specifications are guaranteed and apply across the recommended operating conditions.
Typical values apply at VD = 3.3 V, VIO1 = 3.3 V, VIO2 = 3.3 V, VA = 5 V, and 25 °C unless otherwise stated. Parameters
are tested in production unless otherwise stated.
Table 2. DC Characteristics
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
671
850
1049
mW
FM Mode
Total Supply Power
VA Supply Current
IVA
121
130
139
mA
VD Supply Current
IVD
47
60
79
mA
VA Supply Power Down
Current
IVA
20
90
170
µA
VD Supply Power Down
Current
IVD
5
20
50
µA
707
900
1100
mW
AM Mode
Total Supply Power
VA Supply Current
IVA
129
140
147
mA
VD Supply Current
IVD
47
60
81
mA
VA Supply Power Down
Current
IVA
20
90
170
µA
VD Supply Power Down
Current
IVD
5
20
50
µA
*Note: See "7. I2C Control Bus" on page 44.
4
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Si4770/77-A20
Table 2. DC Characteristics (Continued)
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Interface Supplies
VIO1 Supply Current
IVIO1
0.1
0.5
0.82
mA
VIO2 Supply Current
IVIO2
0.1
0.2
0.5
mA
VIO1 Supply Power Down
Current*
IPD
150
250
420
µA
VIO2 Supply Power Down
Current*
IPD
5
20
150
µA
Inputs Pins SCL, SDA, RSTB, A0, A1
High Level Input Voltage
VIH
0.7 x VIO1
—
—
V
Low Level Input Voltage
VIL
—
—
0.3xVIO1
V
High Level Input Current
IIH
VIN = VI01 = 3.6 V
–10
—
10
µA
Low Level Input Current
IIL
VIN = 0 = V,
VI01 = 3.6 V
–10
—
10
µA
Input Pins DCLK, DFS
High Level Input Voltage
VIH
0.7 x VIO2
—
—
V
Low Level Input Voltage
VIL
—
—
0.3 x VIO2
V
High Level Input Current
IIH
VIN = VI02 = 3.6 V
–10
—
10
µA
Low Level Input Current
IIL
VIN = 0 V,
VI02 = 3.6 V
–10
—
10
µA
2.52
—
—
V
—
—
1.08
V
Input Pins GPIO1, GPIO2
GPIO1 and GPIO2
are internally regulated at 3.6 V
High Level Input Voltage
VIH
Low Level Input Voltage
VIL
High Level Input Current
IIH
VIN = 3.6 V
–10
—
10
μA
Low Level Input Current
IIL
VIN = 0 V
–10
—
10
μA
High Level Output Voltage
VOH
Output is common
drain output with
internal 10 k pullup to VIO1
0.8xVIO1
—
—
V
Low Level Output Voltage
VOL
IOUT = –500 μA
—
—
0.2xVIO1
V
Output Pins INTB
*Note: See "7. I2C Control Bus" on page 44.
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Si 4770/ 77-A 20
Table 2. DC Characteristics (Continued)
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
High Level Output Voltage
VOH
Output is common
drain output with
external 4.7 k
pull-up to VIO1
0.8xVIO1
—
—
V
Low Level Output Voltage
VOL
IOUT = –500 μA
—
—
0.2xVIO1
V
High Level Output Voltage
VOH
GPIO1 and GPIO2
are internally regulated at 3.6 V,
IOUT = +500 μA
2.88
—
—
V
Low Level Output Voltage
VOL
IOUT = –500 μA
—
—
0.72
V
Output Pins SDA
Output Pins GPIO1, GPIO2
Output Pins IQCLK, IQFS, IOUT, QOUT, DFS, DCLK, DOUT
High Level Output Voltage
VOH
IOUT = 500 µA
0.8 x VIO2
—
—
V
Low Level Output Voltage
VOL
IOUT = –500 µA
—
—
0.2 x VIO2
V
*Note: See "7. I2C Control Bus" on page 44.
6
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Rev. 0.9 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • September 1, 2021
Si4770/77-A20
Table 3. Digital Audio Interface Characteristics*
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
DCLK Input Cycle Time
tCYC: DCLK
70
—
—
ns
DCLK Input Pulse Width
High
tHI: DCLK
0.4 x tCYC:DCLK
—
0.6 x tCYC:DCLK
ns
DCLK Input Pulse Width
Low
tLO: DCLK
0.4 x tCYC:DCLK
—
0.6 x tCYC:DCLK
ns
DFS Setup Time
tSU:DFS
10
—
—
ns
DFS Hold Time
tHD:DFS
5
—
—
ns
DOUT ouTput Delay
tPD:DOUT
0
—
35
ns
Capacitive Loading
CB
VIO2 < 1.33 V
—
—
10
VIO2 > 1.33 V
—
—
15
tHI:DCLK
tLO:DCLK
pF
*Note: Guaranteed by characterization.
tCYC:DCLK
DCLK in
tHD:DFS
tSU:DFS
DFS in
tPD:DOUT
DOUT out
Figure 1. Digital Audio
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Si 4770/ 77-A 20
Table 4. Digital Zero-IF I/Q Interface Characteristics (Si4777 Only)1
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V)
Parameter
Symbol
Min
Typ
Max
Unit
tCYC:IQCLK
0.8 x per
per2
1.2 x per
ns
IQCLK Output Pulse Width High
tHI:IQCLK
0.22 x per
—
0.59 x per
ns
IQCLK Output Pulse Width Low
tLO:IQCLK
0.41 x per
—
0.78 x per
ns
IQFS Output Delay
tPD:IQFS
0
—
(0.5 x per) + 18
ns
IQFS Output Setup to IQCLK
Rise3
tSU:IQFS
(0.5 x per) – 18
—
—
ns
IOUT Output Delay
tPD:IOUT
0
—
(0.5 x per) + 18
ns
QOUT Output Delay
tPD:QOUT
0
—
(0.5 x per) + 18
ns
IOUT Output Setup to IQCLK rise3
tSU:IOUT
(0.5 x per) – 18
—
—
ns
QOUT Output Setup to IQCLK
Rise3
tSU:QOUT
(0.5 x per) – 18
—
—
ns
IQCLK Output Cycle Time
Test
Condition
Notes:
1. Guaranteed by characterization.
2. per is the IQCLK I/Q bit clock period. Refer to Table 15 on page 35 for IQCLK bit clock frequencies.
3. Minimum time the Si4770/77-A20 will produce between valid output and the next rising edge of IQCLK
tCYC:IQCLK Max
tCYC:IQCLK Min
IQCLK out
tHI:IQCLK MIN
tLO:IQCLK MAX
tHI:IQCLK MAX
tLO:IQCLK MIN
tPD:IQFS MAX
tSU:IQFS
tPD:IQFS MIN
IQFS out
tPD:IOUT MAX
tSU:IOUT
tPD:IOUT MIN
IOUT out
tPD:QOUT MAX
tSU:QOUT
tPD:QOUT MIN
QOUT out
Figure 2. Digital Zero-IF I/Q
8
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Si4770/77-A20
Table 5. Reference Clock and Crystal Characteristics
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
RCLK Supported
Frequencies
—
36.4
37.8
37.209375
—
MHz
RCLK Frequency
Tolerance
–100
—
100
ppm
100 Hz offset
—
—
–86
dBc/Hz
1 kHz offset
—
—
–101
dBc/Hz
10 kHz offset
—
—
–108
dBc/Hz
≥ 100 kHz offset
—
—
–122
dBc/Hz
—
7
—
pF
400
mVPP
Reference Clock, Pin RCLK
RCLK = 36.4 MHz, 37.8 MHz, 37.209375 MHz
Phase Noise
Input Capacitance
Input Voltage
AC coupling capacitor = 1 µF
Square wave input
AC coupling capacitor = 1 µF
Sine wave input
300
—
900
mVPP
Crystal Frequency
—
36.4
37.8
37.209375
—
MHz
Crystal Frequency
Tolerance
–100
—
100
ppm
5
—
21.8
pF
Crystal Oscillator, Pins XTAL1, XTAL2
Load Capacitance, Programmable, Each Pin to
GND
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Si 4770/ 77-A 20
Table 6. I2C Control Interface Characteristics
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V)
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Pins SCL, SDA
SCL Frequency
fSCL
0
—
400
kHz
SCL Low Time
tLOW
1.3
—
—
µs
SCL High Time
tHIGH
0.6
—
—
µs
SCL Input to SDA Setup
(START)
tSU:STA
0.6
—
—
µs
SCL Input from SDA Hold
(START)
tHD:STA
0.6
—
—
µs
SDA Input to SCL Setup
tSU:DAT
100
—
—
ns
SDA Input from SCL Hold
tHD:DAT
0
—
900
ns
SDA Output Delay
tPD:DAT
300
—
900
ns
SCL Input to SDA Setup
(STOP)
tSU:STO
0.6
—
—
µs
STOP to START Time
tBUF
1.3
—
—
µs
SDA Output Fall Time
tf:OUT
—
250
ns
—
300
ns
SDA Input, SCL Rise/Fall
Time
tf:IN, tr:IN
CB
20 + 0.1 ----------1pF
CB
20 + 0.1 ----------1pF
Capacitive Loading
CB
—
—
50
pF
Pulse Width Rejected by
Input Filter
tSP
—
—
50
ns
10
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Si4770/77-A20
SCL
SDA
tSU:STA tHD:STA
tLOW
START
tr:IN
tHIGH
tr:IN
tf:IN
tSP
tSU:STO
tBUF
70%
30%
70%
30%
tHD:DAT tSU:DAT
tf:IN,
tf:OUT
tPD:DAT
STOP
START
Figure 3. I2C Control Interface Read and Write Timing Parameters
SCL
SDA
(Write)
Command
7-0
A6-A0, 0
START
SDA
(Read)
ADDRESS + R/W
ACK
ADDRESS + R/W
Figure 4.
ACK
Status
7-0
A6-A0, 1
START
DATA
Arg1
7-0
I2
ACK
DATA
DATA
ACK
STOP
ACK
STOP
Response
7-0
ACK
DATA
C Control Interface Read and Write Timing Diagram
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11
Rev. 0.9 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • September 1, 2021
Si 4770/ 77-A 20
Table 7. FM Receiver Characteristics
(TAMB = –40 to 85 °C, VA = 4.5 to 5.5 V, VD = 2.7 to 3.6 V, VIO1 = 1.7 to 3.6 V, VIO2 = 1.2 to 3.6 V. Typical values measured at
TAMB = 25 °C, FM modulation (L = R), FMOD = 1 kHz, FDEV = 22.5 kHz, Deemphasis = 75 µsec, RF level = 60 dBµV, and
FRF = 98 MHz in application circuit unless otherwise specified)
Min
Typ
Max
Unit
Input Frequency
Parameter
64
—
108
MHz
Frequency Step
Resolution
10
—
200
kHz
—
—
100
ms
—
1.5
—
ms
At LOUT and ROUT pins
—
20
—
ms
Audio THD