Ad
related to: how to solve diode problems
Search results
Results from the WOW.Com Content Network
The Shockley diode equation relates the diode current of a p-n junction diode to the diode voltage .This relationship is the diode I-V characteristic: = (), where is the saturation current or scale current of the diode (the magnitude of the current that flows for negative in excess of a few , typically 10 −12 A).
Shockley derives an equation for the voltage across a p-n junction in a long article published in 1949. [2] Later he gives a corresponding equation for current as a function of voltage under additional assumptions, which is the equation we call the Shockley ideal diode equation. [3]
DAEs assume smooth characteristics for individual components; for example, a diode can be modeled/represented in a MNA with DAEs via the Shockley equation, but one cannot use an apparently simpler (more ideal) model where the sharply exponential forward and breakdown conduction regions of the curve are just straight vertical lines.
A well known application of this method is the approximation of the transfer function of a pn junction diode. The transfer function of an ideal diode has been given at the top of this (non-linear) section. However, this formula is rarely used in network analysis, a piecewise approximation being used instead.
The characteristic curve (curved line), representing the current I through the diode for any given voltage across the diode V D, is an exponential curve. The load line (diagonal line) , representing the relationship between current and voltage due to Kirchhoff's voltage law applied to the resistor and voltage source, is
A diode can be formed away from a MOSFET source/drain, for example, with an n+ implant in a p-substrate or with a p+ implant in an n-well. If the diode is connected to metal near the gate(s), it can protect the gate oxide. This can be done only on nets with violations, or on every gate (in general by putting such diodes in every library cell).
The actual threshold is very close to zero, but is not zero. It equals the actual threshold of the diode, divided by the gain of the opamp. This basic configuration has a problem, so it is not commonly used. When the input becomes (even slightly) negative, the opamp runs open-loop, as there is no feedback signal through the diode.
Surface reconstruction is an inverse problem. The goal is to digitally reconstruct a smooth surface based on a large number of points p i (a point cloud) where each point also carries an estimate of the local surface normal n i. [7] Poisson's equation can be utilized to solve this problem with a technique called Poisson surface reconstruction. [8]
Ad
related to: how to solve diode problems