SI4031-B1-FM Silicon Laboratories Inc, SI4031-B1-FM Datasheet - Page 14

• Manufacturer Part Number: SI4031-B1-FM
• Description: IC TX 240-930MHZ -8-13DB 20VQFN
• Manufacturer: Silicon Laboratories Inc
• Type: ISM Transmitterr

Specifications of SI4031-B1-FM

• Package / Case: 20-VQFN
• Frequency: 240MHz ~ 930MHz
• Applications: General Purpose
• Modulation Or Protocol: FSK, GFSK, OOK
• Data Rate - Maximum: 256 kbps
• Power - Output: 13dBm
• Current - Transmitting: 30mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 1.8 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Operating Frequency: 240 MHz to 930 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Operating Supply Voltage: 1.8 V to 3.6 V
• Supply Current: 30 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Memory Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Si4030/31/32-B1
2. Functional Description
The Si4030/31/32 are ISM wireless transmitters with continuous frequency tuning over their specified bands which
encompasses 240–960 MHz. The wide operating voltage range of 1.8–3.6 V and low current consumption makes
the Si4030/31/32 an ideal solution for battery powered applications.
The RF carrier is generated by an integrated VCO and  Fractional-N PLL synthesizer. The synthesizer is
designed to support configurable data rates, output frequency, frequency deviation, and Gaussian filtering at any
frequency between 240–960 MHz. The transmit FSK data is modulated directly into the  data stream and can be
shaped by a Gaussian low-pass filter to reduce unwanted spectral content.
The Si4032’s PA output power can be configured between +1 and +20 dBm in 3 dB steps, while the Si4030/31's
PA output power can be configured between –8 and +13 dBm in 3 dB steps. The PA is single-ended to allow for
easy antenna matching and low BOM cost. The PA incorporates automatic ramp-up and ramp-down control to
reduce unwanted spectral spreading. The +20 dBm power amplifier of the Si4032 can also be used to compensate
for the reduced performance of a lower cost, lower performance antenna or antenna with size constraints due to a
small form-factor. Competing solutions require large and expensive external PAs to achieve comparable
performance.
The Si4030/31/32 is designed to work with a microcontroller, crystal, and a few external components to create a
very low cost system. Voltage regulators are integrated on-chip which allows for a wide operating supply voltage
range from +1.8 to +3.6 V. A standard 4-pin SPI bus is used to communicate with an external microcontroller.
Three configurable general purpose I/Os are available. A complete list of the available GPIO functions is available
in “AN466: Si4030/31/32 Register Descriptions.”
2.1. Operating Modes
The Si4030/31/32 provides several operating modes which can be used to optimize the power consumption for a
given application.
Table 8 summarizes the operating modes of the Si4030/31/32. In general, any given operating mode may be
classified as an active mode or a power saving mode. The table indicates which block(s) are enabled (active) in
each corresponding mode. With the exception of the SHUTDOWN mode, all can be dynamically selected by
sending the appropriate commands over the SPI. An “X” in any cell means that, in the given mode of operation,
that block can be independently programmed to be either ON or OFF, without noticeably impacting the current
consumption. The SPI circuit block includes the SPI interface hardware and the device register space. The 32 kHz
OSC block includes the 32.768 kHz RC oscillator or 32.768 kHz crystal oscillator and wake-up timer. AUX
(Auxiliary Blocks) includes the temperature sensor, general purpose ADC, and low-battery detector.
14
*Note: Using Si4030/31 at +13 dBm using recommended reference design.
SHUTDOWN
Mode Name
TRANSMIT
STANDBY
SENSOR
TUNING
READY
SLEEP
(Register contents
(Register contents
Digital LDO
retained)
OFF
lost)
ON
Table 8. Operating Modes
OFF
SPI
ON
ON
ON
ON
ON
ON
32 kHz OSC
Circuit Blocks
Rev 1.1
OFF
OFF
ON
X
X
X
X
AUX
OFF
OFF
ON
X
X
X
X
30 MHz
XTAL
OFF
OFF
OFF
OFF
ON
ON
ON
OFF
OFF
OFF
OFF
OFF
PLL
ON
ON
OFF
OFF
OFF
OFF
OFF
OFF
ON
PA
30 mA*
450 nA
800 µA
8.5 mA
15 nA
1 µA
1 µA
I
VDD