We resolved this by exploiting a capacitor already in place from B to a previously floating node, adding a resistance to ground, essentially creating a tank-circuit which seems to be sufficiently low impedance for 50Hz s.t. the diodes no longer become forward-bi...
It is necessary to provide a path for this input bias current to flow, and must also be within the common-mode input voltage range - which for this part is not an issue as it is RRI. Remember that an offset will also occur due to this bias current and the resistance you connect t...
performance in terms of wider input-output voltage swing, lower input resistance, and larger output resistance compared with the conventional high-swing ... X Zhang,EI El-Masry - 《Circuits & Systems II Express Briefs IEEE Transactions on》 被引量: 58发表: 2004年 0.5‐V bulk‐driven OTA an...
Compared to the difficulty of CDM measurement, measuring positive input common-mode capacitance, CCM+, to ground directly is relatively easy. By putting a large series resistance in the noninverting pin of the op amp and applying a sine wave or noise source, the –3 dB frequency re...
The output of your sensor represents a voltage source (probably an opamp) with some series source resistanceRsRs. If you connect that output to the load resistanceRLRL(200−250kΩ200−250kΩ) of the analog input card, there will be some voltage drop acrossRsRs...
The gate terminals of the field effect transistors are connected to the input terminal. A control device adjusts a resistance of the load path of at least one of the field effect transistors as a function of a particular value selected for the supply voltage. 展开 ...
A preamplifier optimised for use in measurements of capacitance at frequencies of 1-2 kHz has an equivalent series noise resistance of 40 Omega when presented with a source of 1nF. The input device is a low-noise JFET, and its performanc... GW Small,KE Leslie - 《Journal of Physics E ...
We'll not run through all the math here, but in summary, a 100K input resistance applied to a non-inverting OPA1612 opamp with 1.1 nV/rthz voltage noise and 1.7 pA/rthz current noise gives 177 nV/rthz of noise, which is -135 dBV/rthz. Not exact, but in the ballpark of what we...
Use an opamp with ESD protection diodes; low bias current- usually a JFET or CMOS opamp comes into a play, then calculate a minimal resistance. simulate this circuit– Schematic created usingCircuitLab EDIT: You won't find a max current for LM358, because it h...
Its architecture is based on the use of current inverters to sense the input currents while providing a very low input resistance, 23 Ω. The opamp provides a maximum output swing of 700 μA, with an input offset current of 3.5 nA. The differential gain achieved is 65.5 dB, and the ...