Questions tagged [current-mirror]
Current mirror circuits enable the mirroring of the current flowing somewhere else in the circuit onto a path of interest. Typically used in non intrusive load current measurements.
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Current Mirror In Differential Pair Amplifier
I am designing a differential pair that is connected to a current mirror. I have calculated the drain resistors of the differential pair to draw around 16.5 mA and achieve a gain of 20 dB. When I ...
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How to practically adjust a high-voltage cascode current mirror to bias a cascode amplifier without the reference resistor?
I’m designing a cascode amplifier biased by a cascode current mirror, and I need a drain current of about 200 mA.
To set the reference current, I used a resistor:
Rref = 2 kΩ
$$I_D = \frac{400 V - 4.5 ...
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How does this current mirror amplifier circuit work?
In this answer a circuit is proposed for a current sensing application:
The circuit is comprised of two current mirrors. I understand how a basic current mirror works, but this configuration baffles ...
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How is the voltage calculated in this current mirror implementation?
I've seen this kind of implementation of a double bjt current mirror (Pull-Push current mirror?) in the 7805 Voltage regulator. I´m trying to understand the way it works by making a simple model on ...
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Understanding Current Mirror circuit that inverts voltage
Yesterday I asked a question here asking for help on inverting an input voltage (0-VCC V) around a fixed voltage. For my case, I had a 5V DC source and the fixed voltage is supposed to be 2.5V, ...
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Circuit to sense and mirror current in the output
I am trying to design a circuit that measures the current drawn by the output load and mirrors that current somewhere else. The idea is shown in the figure where we have an amplifier driving the load. ...
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Analysis of current mirror in LM339 comparator
I am designing a very simple comparator, using the LM339 as a reference. However, I don't quite understand the purpose of what resembles a current mirror implemented by Q5 and Q6 in the circuit ...
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Supply Independent Current Mirror MOSFET Sizing
I'm trying to design a circuit that outputs 4 current references of 1uA each (from PMOS). Assuming that I have a supply of 3.3V (+/- 10%) and that the maximum current for the current reference ...
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Understanding results and plots from analog lab?
I'm doing a lab in analog, but I don't see a resemblance in the lab and lecture material at all, except that both talked about current mirrors.
I have the following current mirror circuit in a ...
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Using a current mirror for high-speed switching of a laser diode
I am looking to design a circuit to pulse a 532 nm laser diode at approximately constant optical power output (current of ~200 mA), with pulse widths of ~1-10 us with a rise/fall time on the order of ...
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Wilson mirror operation
I have this basic Wilson current mirror circuit;
And I'm trying to get my head around how it set's a near equal current in R1 and the load. I think I understand the basic theory, and how the circuit ...
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Biasing common-source NMOS with active load and fixed Vgs
I came across this circuit, a common-source NMOS amplifier with PMOS current mirror as active load AND a fixed DC voltage level at the NMOS gate.
Since we're using a current mirror, we are, by ...
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Small signal analysis confusion: which zero load condition should I use?
Which zero load condition should I use when trying to find Ri?
Zero load, defined in our class, is when \$I_{out}=0 \space or \space V_{out}=0\$. I was trying to solve this current mirror circuit, and ...
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Understanding biasing circuit for RF PHEMT transistor
I am looking into the datasheet of a SAV-541+ E-PHEMT RF transistor, and looking at the recommended biasing circuit, im not sure how the drain current is determined.
Above is the picture from the ...
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An integrated amplifier circuit with current mirror transistors will not amplify the input voltage (Vin)
I can't figure out why my Multisim amplifier circuit isn't amplifying the DC input voltage. I double-checked the settings for each transistor, as well as my calculated gate voltage for transistor Q1, ...
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