IQD announces evaluation board for standard oscillators
Designed as a simple means of testing an oscillator, IQD Frequency Products has introduced the IOSC-EV board to test standard surface mount clock oscillators, VCXOs or TCXO/VCTCXOs.
According to IQD, the board means there is no need to worry about designing and building a test circuit. The IOSC-EV board comes with six smaller boards that can be snapped from the side of the main board and onto which different size four pad packaged oscillators can be soldered. The smaller board can be soldered to the main PCB. The six package sizes are 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.
The board includes a regulated and filtered power supply which can be set to between 1.8 and 5.0V to counter the effect of power supply noise on the frequency of the oscillator. For users who want to inject noise on the power rail and monitor the effect during testing, the board also includes the option to apply power directly to the PCB.
The enable/disable function can be tested by a manual switch to observe the effect on the current draw. There is also the ability to drive this input high or low from a digital source to measure the enable time. For products with a voltage control input, such as a VCXO or VCTCXO, there is a potentiometer on the PCB to allow developers to trim out the frequency tolerance and the effect of the soldering, to bring the frequency to nominal.
This can also be used to manually adjust the voltage control input and measure the effect on the frequency. For sensitive products, such as VCTCXOs, there is an option to trim out the tolerance, measure the potentiometer resistance, then replace with fixed resistors for reduced noise, for optimum stability, jitter, and phase noise. The voltage control input can also be adjusted from an external analogue source.
On the output stage the IOSC-EV board offers three load configurations. CMOS output can be terminated into a 15pF load, then buffered to give a 50 Ohm output impedance that can be connected directly to test equipment such as frequency counters. Clipped sine wave output can be terminated into 10 kOhm 10pF load, then buffered to give a 50 Ohm output impedance that can be terminated directly into test equipment. The oscillator output can also be accessed directly, without any buffers or load. All these outputs are terminated in an SMA connector.
The evaluation board is available in two options. The first is a non-populated PCB which is supplied with the bill of materials required to operate the test circuit, the second option is a populated board ready to be used.
The non-populated version will be available free of charge to the first 400 visitors to the IQD Frequency Products’ stand at Electronica 2018 (Hall A6-314).
