Search results
Results from the WOW.Com Content Network
Conversely, a current source provides a constant current, as long as the impedance of the load is sufficiently lower than the current source's parallel impedance (which is preferably very high and ideally infinite). In the case of transistor current sources, impedances of a few megohms (at low frequencies) are typical. Because power is current ...
In electronics, a constant current system is one that varies the voltage across a load to maintain a constant electric current.When a component is indicated to be driven by a constant current, the driver circuit is, in essence, a current regulator and must appear to the component as a current source of suitable reliability.
It is known as a current-limiting diode (CLD) or current-regulating diode (CRD). Internal structure. It consists of an n-channel JFET with the gate shorted to the source, which functions like a two-terminal current limiter (analogous to a voltage-limiting Zener diode). It allows a current through it to rise to a certain value, but not higher.
where this time is the charge density, is the current density vector, and is the current source-sink term. The current source and current sinks are where the current density emerges > or vanishes <, respectively (for example, the source and sink can represent the two poles of an electrical battery in a closed circuit).
There are three main specifications that characterize a current mirror. The first is the transfer ratio (in the case of a current amplifier) or the output current magnitude (in the case of a constant current source CCS). The second is its AC output resistance, which determines how much the output current varies with the voltage applied to the ...
A Widlar current source is a modification of the basic two-transistor current mirror that incorporates an emitter degeneration resistor for only the output transistor, enabling the current source to generate low currents using only moderate resistor values. [1] [2] [3]
A direct current circuit is an electrical circuit that consists of any combination of constant voltage sources, constant current sources, and resistors. In this case, the circuit voltages and currents are independent of time. A particular circuit voltage or current does not depend on the past value of any circuit voltage or current.
The compliance of a current source, that is, the range of output voltage over which the output current remains approximately constant, affects the potentials available to bias and operate the circuitry in which the source is embedded.