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Derivation of npn BJT emitter,base and collector currents in forward active mode

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Essentially BJT is just two neighboring pn junctions put back to back. BJT: a first pass (7.2) Fact In an IC npn transitor the emitter donor concentration \(N_{dE}\) is much greater than the base acceptor concentration \(N_{aB}\) which is much greater than the collector donor concentration \(N_{dC}\) \[ N_{dE}\gg N_{aB}\gg N_{dC} \] therefore the thermal equilibrium minority carrier concentrations in the emitter, base, and collector are \[ p_{nEo}=\frac{n^2_i}{N_{dE}}\ll n_{pBo}=\frac{n^2_i}{N_{aB}}\ll p_{nCo}=\frac{n_i^2}{N_{dC}} \] Forward-active regime: edge minority carrier concentration profile vs that of thermal equilibrium. Assume steady state short base diode conditions You should realize the heights of the thermal equilibrium minority carrier concentrations drawn in diagram above is a direct consequence of Fact 70 . This will again will be represented in the diagram Figure fluxpath where we account for flux paths of minority ca...
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Long Term Potentiation: How your brain learns - signalling pathway in synapse

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LTP is a key process underlying learning and memory. It involves the strengthening of synaptic connections through repeated stimulation, allowing neurons to communicate more effectively. This phenomenon is primarily mediated by NMDA (N-methyl-D-aspartate) glutamate receptors and other molecular mechanisms. Role of NMDA and AMPA Receptors Glutamate , the major excitatory neurotransmitter in the CNS, plays a critical role in synaptic transmission. It binds to two key receptors: AMPA Receptors : Ionotropic receptors that allow Na + and K + ions to pass when activated, leading to fast excitatory synaptic transmission . NMDA Receptors : Normally blocked by Mg 2+ ions, preventing ion flow. Definition: In this context, sensitivity refers to for the same amount of stimulation (AP to CA3), the response (AP of CA1) is greater. Phases of LTP A. Normal Synaptic Transmission (Before LTP) ...
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