Miscellaneous

Tuyen D. Le May 19, 2022 [Power-Electronics] #misc

General information

Connector

Blade connectors (lower half of photo). Ring and spade terminals (upper half). Bullet terminals, male and female (right-center, with blue wires)


Blade connector


Split-ring or lugs terminals for 2.5 mm² wire.


Banana jack connector

Using crimping tool to join wire to the connector.


Crimping tool

RJ45 pinout and connection

Refer to Ethernet Wiring
Only two couple wires 1-2,3-6 are enough for 100 Mb/s transmission.

Power factor


Apparent power, reactive power and real power

The picture shows the relationship between "Apparent Power", "Reactive Power" and "Real Power".

Reactive power is an AC power flow through the operation of the inductors and capacitors. This kind of power doesn't contribute to the

See more at What is the role of reactive power in transmission networks?

Interfacing Matlab Simulink with Plexim PLECS

Potentiometers

P16NP504KAB15 Vishay / Sfernice | Mouser Denmark

There's a LOT of files on the official LTwiki.

For potentiometers look in (source):

http://ltwiki.org/files/LTspiceIV/lib/sym/Pot&Sw/ for the symbols, and
http://ltwiki.org/files/LTspiceIV/lib/sub/Pote.lib is the associated library, (including both potentiometer_standard.lib and potentiometer_tapped.lib with documentation and sample files at
http://ltwiki.org/files/LTspiceIV/examples/LtSpicePlus/Discretos/Sw&Pote/

MOSFET

N-channel MOSFET

Physical view

Current flows between diffusion terminals if the voltage on the Gate large enough to create a conducting channel, otherwise the MOSFET is off and the diffusion terminals are not connected. ¹

physical view

Electrical view

The four terminals of a Field Effect Transitor are Gate, Source, Drain and Bulk.

electrical view

Circuit symbol

MOSFET and JFET circuit symbols

P-channel
N-channel
	JFET (they are only in depletion mode)	MOSFET enhancement mode	MOSFET enhancement mode (no bulk)	MOSFET enhancement mode (no bulk)	MOSFET depletion mode (switched on)

{% include tldr.html box="TRICK" tldr="The arrow forms the pn junction from the 'buck' to the 'gate' in the symbol of MOSFET" %}

When a channel exists in a MOSFET, current can flow from source to drain as well as from drain to source - it's just a matter of how the device is connected in the circuit ². Conventional current flows from Drain to Source in an N Channel MOSFET.

N-channel MOSFET

When a channel exists in a MOSFET, current can flow from drain to source or from source to drain - it's a function of how the device is connected in the circuit. The conduction channel has no intrinsic polarity - it's kind of like a resistor in that regard.

The intrinsic body diode inside the MOSFET is in parallel with the conduction channel, however. When the conduction channel is present, the diode is shunted and current flows through the path of least resistance (the channel). When the channel is off, the diode is in circuit and will either conduct or block depending on the drain-source current polarity.

As your picture shows, there are both N-channel and P-channel devices, as well as enhancement mode and depletion mode devices. In all of these cases, current can flow from source to drain as well as from drain to source - it's just a matter of how the device is connected in the circuit.

Your picture does not show the intrinsic diode in the devices - the arrow point towards or away from the gate is an indication of the channel type (N-channel points towards the gate, P-channel points away from the gate).

n-channel enhancement MOSFET

This symbol shows you the inherent diode between drain and source.

N-channel enhancement devices need a voltage on the gate higher than the source in order to create a conduction channel. (Enhancement devices don't have a channel automatically, and need gate voltage to create one - because it's N-channel Vgate>Vsource for this to happen.)

P-channel enhancement devices need a voltage on the gate lower than the source in order to create a conduction channel. (Enhancement devices don't have a channel automatically, and need gate voltage to create one - because it's P-channel Vgate<Vsource for this to happen.)

N-channel delpetion devices have a channel by default, and need a voltage on the gate lower than the source in order to turn the channel off. The channel can be widened to a certain extent by increasing the gate-to-source voltage above 0.

P-channel depletion devices also have a channel by default, and need a voltage on the gate higher than the source in order to turn the channel off. The channel can be widened to a certain extent by decreasing the gate-to-source voltage below 0.

References

Chris Terman. 6.004 Computation Structures. Spring 2017. Massachusetts Institute of Technology: MIT OpenCourseWare, https://ocw.mit.edu. License: Creative Commons BY-NC-SA.
²: Adam Lawrence, In an NMOS, does current flow from source to drain or vice-versa?, URL (version: 2012-11-11)

Magnetic core

Ferrite Power Materials Summary		F	P	R	J	W+
µi (20 gauss)	25˚C	3,000	2,500	2,300	5,000	10,000
µp (2000 gauss)	100˚C	4,600	6,500	6,500	5,500	12,000
Saturation Flux Density ($B_{max}$ Gauss)	25˚C	4,900	5,000	5,000	4,300	4,300
	100˚C	3,700	3,900	3,700	2,500	2,500
Core Loss (mw/cm3) (Typical) @100 kHz, 1000 Gauss	25˚C	100	125	140	low-level power transf.
	60˚C	180	80*	100
	100˚C	225	125	70

Core Geometries

Core Geometries		Core Geometries
Classical E		ETD
EFD		EP
Pot core		RM core
PQ core		PM core

Core selection

$A_p = A_E A_W = \frac{P_{out}}{K_c K_t B_{max} F_{SW} J} 10^4$

$A_P$: product of window area and core area, $cm^2$
$A_E$: effective cross section of the core, $cm^2$
$A_W$: window area (or winding area), $cm^2$
At: surface area of the transformer

calculate Wa and Ac

$\begin{align*} & A_e = 20 \times 27.4 = 540 \; mm^2 \\ & A_W \text{ (often referred in datasheets as )} A_N = 4.35 \; cm^2\\ & A_P = A_E × A_W = 5.4 \times 3.24 = 5.4 × 4.35 = 23.5 \; cm^4 \end{align*}$

References

https://en.wikipedia.org/wiki/Magnetic_core
https://e-magnetica.pl/list_of_ferrite_core_types
Transistor, SMPS Transformer Area of Product, URL (version: 2020-06-11): https://electronics.stackexchange.com/q/504104

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