User's Manual

4 SWA51 Functional Block Diagram and Functional Description
Figure 1: SWA51 Module Block Diagram
The SWA51 module is available in 2 variations; digital input transmitter module or digital output
receiver module.
There are three available I2S digital audio data inputs/outputs, each of these can be configured to operate as either
a master or a slave - depending on the application, the I2S ports can operate simultaneously as either inputs or
outputs. When configured as slaves, the I2S inputs/outputs can be independently clocked by external masters. In
addition, MCLK can be output from the module to provide a reference clock source to an external ADC or DAC.
Figure 1 shows the block diagram of the SWA51 module. The hardware for the audio input
(transmit) and audio output (receive) versions of the module is identical and only the firmware loaded onto the
module determines its function.
The highly integrated nature of the AV5100 transceiver IC results in few external components being required for the
SWA51 module design. 2 printed PCB antennas are used to achieve increased range, and to achieve antenna
spatial diversity. The simple RF path consists only of the antennas, associated tuning components, shield can, the
RF switch and two baluns, one connected to each of the RF input and RF output ports on the AV5100 IC.
A 16MHz crystal oscillator generates the AV5100 fundamental system clock used as the basis for all RF and digital
audio clocks.
A 2Mb flash memory chip is used to store the module’s application firmware. The AV5100 is able to boot from
internal ROM upon first power up, which enables programming the flash chip with the application firmware r through
USB. In addition, Over-the-air Firmware upgrade capability can be enabled through the application firmware. The
module can be controlled from an external host device via the I2C Slave or the SPI Slave data interfaces. The I2C
master port allows the module to control other system audio devices such as a sub-woofer amplifier system without
having to add another MCU to the product design. Up to 119 additional GPIOs are available on the SWA51 module
(not including I2C and I2S signals) for implementing different UI features on the target application. The resources
mentioned above can be leveraged to implement low cost sub-woofer designs as outlined below.