AS3977-BQFU austriamicrosystems, AS3977-BQFU Datasheet - Page 20

• Manufacturer Part Number: AS3977-BQFU
• Description: IC RF TRANSMITTER FSK 16-QFN
• Manufacturer: austriamicrosystems

Specifications of AS3977-BQFU

• Frequency: 300MHz ~ 928MHz
• Applications: ISM
• Modulation Or Protocol: FSK
• Data Rate - Maximum: 100 kbps
• Power - Output: 10dBm
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 2 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-VQFN Exposed Pad, 16-HVQFN, 16-SQFN, 16-DHVQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Memory Size: -
• Current - Transmitting: -

AS3977
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
Figure 6. Operation Mode Relations
Transmitter Control Interface
The AS3977 is controlled by an external micro controller (µC) via. a bi-directional communication interface (serial
digital interface, SDI). The SDI enables data to be read from and written to internal control registers without the
necessity of an internal clock signal. Analog de-bouncing of clock and data input is implemented in order to improve
the overall system reliability.
The SDI-control interface includes a state machine, which expects a command control word as first byte and in
reference to this byte, the interface is configured as write, read, or transmit operation. This method enables an effective
and easy control of basic transmitter functions. Four preset independent output frequencies and two preset
independent output power levels and modulation types can be selected using the control-command byte, thus enabling
fast channel hopping and/or fast changes to the output power level and modulation type. The selection of the active
output frequency and/or power level and modulation type is done using the so-called command byte.
As an additional feature, the AS3977 provides a configurable clock signal derived from the crystal frequency. The
purpose of this clock signal is to provide a µC clock and to enable data synchronization.
A timer is included to power down (Power Down Mode) the transmitter after a certain time, which is defined as 2
multiplied with the crystal oscillator- Period.
www.austriamicrosystems.com
Software Power Down
ENABLE to LOW for
command via SPI
2
16
XTAL cycles
or
Revision 3.5
Transmit Mode
Clock Enable
Power Down
PLL Enable
Power ON
Hardware
External
Reset
Mode
Mode
Mode
ENABLE is
High Pulse
Command
Command
ENABLE
HIGH
SPI
SPI
20 - 45
16