SI4734-C40-GM Silicon Laboratories Inc, SI4734-C40-GM Datasheet - Page 26

• Manufacturer Part Number: SI4734-C40-GM
• Description: IC RX AM/FM/SW/LW RADIO 20UQFN
• Manufacturer: Silicon Laboratories Inc

Specifications of SI4734-C40-GM

• Frequency: 153kHz ~ 279kHz, 520kHz ~ 1.71MHz, 2.3MHz ~ 26.1MHz, 64MHz ~ 108MHz
• Modulation Or Protocol: AM, FM, SW-LW
• Applications: General Purpose
• Current - Receiving: 19.9mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Features: RSSI Equipped
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 20-UQFN, 20-µQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Sensitivity: -
• Memory Size: -
• Data Rate - Maximum: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

Si4734/35-C40
5.16.3. SPI Control Interface Mode
When selecting SPI mode, the user must ensure that a
rising edge of SCLK does not occur within 300 ns
before the rising edge of RST.
SPI bus mode uses the SCLK, SDIO, and SEN pins for
read/write operations. The system controller can
choose to receive read data from the device on either
SDIO or GPO1. A transaction begins when the system
controller drives SEN = 0. The system controller then
pulses SCLK eight times, while driving an 8-bit control
byte serially on SDIO. The device captures the data on
rising edges of SCLK. The control byte must have one
of five values:





For write operations, the system controller must drive
exactly 8 data bytes (a command and seven arguments)
on SDIO after the control byte. The data is captured by
the device on the rising edge of SCLK.
For read operations, the controller must read exactly 1
byte (STATUS) after the control byte or exactly 16 data
bytes (STATUS and RESP1–RESP15) after the control
byte. The device changes the state of SDIO (or GPO1, if
specified) on the falling edge of SCLK. Data must be
captured by the system controller on the rising edge of
SCLK.
Keep SEN low until all bytes have transferred. A
transaction may be aborted at any time by setting SEN
high and toggling SCLK high and then low. Commands
will be ignored by the device if the transaction is
aborted.
For details on timing specifications and diagrams, refer
to Figure 6 and Figure 7 on page 10.
5.17. GPO Outputs
The Si4734/35 provides three general-purpose output
pins. The GPO pins can be configured to output a
constant low, constant high, or high-impedance. The
GPO pins can be reconfigured as specialized functions.
GPO2/INT can be configured to provide interrupts and
GPO3 can be configured to provide external crystal
support or as DCLK in digital audio output mode.
26
0x48 = write a command (controller drives 8
additional bytes on SDIO).
0x80 = read a response (device drives 1additional
byte on SDIO).
0xC0 = read a response (device drives 16 additional
bytes on SDIO).
0xA0 = read a response (device drives 1 additional
byte on GPO1).
0xE0 = read a response (device drives 16 additional
bytes on GPO1).
Rev. 1.0
5.18. Firmware Upgrades
The Si4734/35 contains on-chip program RAM to
accommodate minor changes to the firmware. This
allows Silicon Labs to provide future firmware updates
to optimize the characteristics of new radio designs and
those already deployed in the field.
5.19. 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.
5.20. Programming with Commands
To ease development time and offer maximum
customization, the Si4734/35 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 partial list of
commands is available in Table 14, “Selected Si473x
Commands,” on page 27.
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. A partial list of
properties is available in Table 15, “Selected Si473x
Properties,” on page 28.
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 Si4734/35, see “AN332: Si47xx
Programming Guide.”