Servo - November 2011

An RF Play Day With Sunray

by Fred Eady • www.servomagazine.com/index.php?/magazine/article/november2011_Eady

The very first electronic building block was called a vacuum tube. If you hail from England, that first electronic building block we call a tube is (still) called a valve. The tube — or valve — was followed by the transistor. Compared to the vacuum tube, a typical transistor was smaller, cool to the touch, and could operate without high voltage power supplies. In reality, tubes had already done everything transistors were about to do. Tubes drove the first computers, amplified the first Hi-Fi recordings, and bent the Earth’s magnetic field as radio waves. The Beatles recorded their first hit song using a valve-based audio console.

It didn’t take long before transistors were ganged into electronic building blocks called integrated circuits. The integrated circuit, or IC, led to solid-state operational amplifiers, elementary logic modules, programmable logic modules, microcontrollers, and radio modules. This month’s discussion will be centered on utilizing the transistor building block from the perspective of a low power RF module and a microcontroller or two.

The RF building block is based on the TI CC2500 and the microcontroller building block is one of the 10 billion units delivered by the folks at Microchip.

The Primary Sunray RF Building Block

The RF engineers at Sunray Technology have produced a pair of 2. 4 GHz radio modules based on the venerable Texas Instruments CC2500 low power radio module. The SRWF-2500 wireless transceiver is

Sunray Technology’s base 2. 4 GHz module. As you can see in Photo 1, the SRWF-2500 is a compact RF building block built up on 0.1 inch headers. Aside from any fancy proprietary RF glue circuitry, there is only one way to wrap circuitry around a CC2500 RF