FAQ #10: What are the main differences between J2100A injection transformer, J2110A solid state inje
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.