Evaluation board tests standard oscillators, VCXOs, TCXOs and VCTCXOs
To quickly and easily test oscillators, the IOSC EVBoard has six smaller boards that can be snapped off the main one and onto which different sized four-pad oscillators can be soldered. The smaller board can then be soldered to the main board, says Wurth Elektronik. The IQD part is available in six package sizes, namely: 1.6 x 1.2mm, 2.0 x 1.6mm, 2.5 x 2.0mm, 3.2 x 2.5mm, 5.0 x 3.2mm and 7.0 x 5.0mm.
Noise in the supply voltage can affect the frequency of the oscillator, so the IOSC-EVBoard contains a regulated and filtered supply voltage. It can be selected between 1.8 and 5.0V to allow the performance of the oscillator to be considered under ideal conditions. It may also be necessary to deliberately introduce noise during testing to observe the consequences and so the board also has the option to connect a supply voltage directly.
The enable/disable function can be tested by manual switching to observe the effect on current draw. It is also possible to set this input to high or low via a digital source to measure the enable time. For products with voltage control input, such as VCXOs and VCTCXOs, the board includes a potentiometer to bring the frequency tolerance and the effect of soldering back to the nominal frequency by pulling. This process can be used to manually adjust the control voltage to simulate the effect on frequency. For sensitive products like VCTCXOs, in addition to pulling the frequency, it is possible to replace the applied potentiometer resistor with a fixed resistor. This leads to better stability and optimised jitter as well as phase noise. The pull input can also be fed via an external analogue source.
There are three configurations for the output signal – there is a CMOS output, a clipped sine or a direct output without buffer or load. All outputs are terminated in an SMA connector.
The evaluation board is available as an unpopulated PCB supplied with the appropriate bill of materials or as a populated board for immediate use. The unpopulated version is currently available free of charge from IQD with the next 200 oscillator sample orders.