# Test Software

## Different Test Softwares

An impedance tuner is an apparatus, which generates controllable reflection factor (Impedance) over a certain frequency range. Focus uses two basic technologies:

a) For frequencies from 100MHz to 110GHz (and above) we use the slide screw technique (models Multi Harmonic MPT, wideband (fundamental) CCMT, harmonic rejection PHT), in which a reflective probe (slug) is inserted into the slot of a low loss slotted transmission line (slabline or waveguide).

b) For frequencies from below 10MHz to 170MHz  we use a lumped element technology (models LFT), whereby variable capacitors are connected with optimized lengths of coaxial cable.

An impedance tuner is an apparatus, which generates controllable reflection factor (Impedance) over a certain frequency range. Focus uses two basic technologies:

a) For frequencies from 100MHz to 110GHz (and above) we use the slide screw technique (models Multi Harmonic MPT, wideband (fundamental) CCMT, harmonic rejection PHT), in which a reflective probe (slug) is inserted into the slot of a low loss slotted transmission line (slabline or waveguide).

b) For frequencies from below 10MHz to 170MHz  we use a lumped element technology (models LFT), whereby variable capacitors are connected with optimized lengths of coaxial cable.

### Noise Parameters

Noise measurements allow the determination of the four Noise Parameters of a device (transistor).  There are four Noise Parameters which fully describe the noise behaviour of an active or passive device at a given frequency.

The Noise Parameters are not load depended, they are only affected by Source Impedance. There exist a simple relation between the four Noise Parameters:

NF calculation formula is the following:

• NFLinear = NFMinLinear + ((4 * Rn / Zo) * (Gs – GammaOpt).Mag2 ) / ((1 + GammaOpt).Mag2 * (1 – Gs.Mag2));

This is the equation of a set of isometric circles on the Smith Chart (Noise Circles) for which the value of the Noise Figure is the Level on each circle. This Circle Representation is only possible because the Noise behaviour of transistors is a Small Signal Phenomenon.

Where:

• NFminLinear is the minimum noise figure in linear.
• Rn is the equivalent noise resistance in Ohms
• Gs is the gamma presented to the DUT at the input (in our case by the tuner).
•  GammaOpt is the optimum gamma (ie: gamma source for which the DUT produces the minimum noise figure).
• Note: Mag2 denotes the magnitude squared.

### Pulsed IV Measurements

Auriga AU-5

Introducing Auriga’s 5th generation pulsed IV/RF characterization system delivers unparalleled performance, capturing measurements with incredible speed and accuracy.

Pulsed IV (current-voltage) measurements have emerged as the preferred method of capturing current-voltage characteristics of active devices such as field effect (FETs) and bipolar junction (BJTs) transistors. With the growing popularity of higher-power devices, like GaN HEMTs, LDMOS, SiC, and graphene, current and voltage requirements are constantly being pushed higher and higher.