What are the main differences between J2100A injection transformer, J2110A solid state injector and the J2111A current injector?
The J2110A is a solid state voltage injector, offering lower noise and wider bandwidth (DC-50+mhz) than a transformer. The J2110A has a 25 ohm output impedance and is limited to +/- 10v input and output levels. Picotest offers two transformers, the J2100A and the J2101A. The difference between the two transformers is the bandwidth. The J2100A offers a low end bandwidth of 1Hz satisfying low frequency measurements such as PFCs, while the J2101A is designed for a higher frequency range starting at 10Hz. The J2101A is most beneficial for linear regulators, LDOs and switching regulators. The J2111A is a current injector with a transconductance of 10ms. The J2111A is a current sink (two actually, one for positive voltages and one for negative voltages. Both are contained inside the J2111A; steering electronics automatically choose the correct path. The device has a precision current port allowing a current to be injected to create a small signal step load and also for output impedance, PSRR and reverse transfer measurements. The device can sink current from voltages above 0.7V and below -0.7V. It will not operate between -0.7V and +0.7V and cannot source current, only sink it. The J2111A is our most popular injector and is the basis for the non-invasive phase margin measurement, which is derived from output impedance.