Robust

Protecting system against wrong polarity input Insert a rectifying diode in series with input, which will “block” power in the circuit if its connected the wrong way. Hence, power dissipation is 0W.

Protecting system against wrong polarity input alt 2 In this solution, where you CAN have power in the circuit even with “wrong” polarity input: P=UI=2*0.7*i [W] dissipated energy. Where 0.7 V is the voltage drop over a diode and 2*0.7 indicates that there are 2 diodes being used each time. i is the input current.

plastic foil (+low cost, low resistance - stability, lower frequencies)

ceramic (+ high stability, high temp, high frequency, long life time (dry), high voltage, high conductivity (wet), - high cost)

electrolytic, tantalum electrolyte, metal/paper (+ low carbon, less fire risk, - big size)

polypropylene (+ low loss, high stability, - big size, costly)

polyester (+ small, low price, - low performance)

polyphenylene sulphide (+ high temp, low losses, high stability, - low voltage rating)

Plastic foil capacitors are used for decoupling, filters, timing circuits. Values: nF, uF.

Electrolytic capacitors come in wet or dry type, polarity sensitive.

Tantalum electrolyte. Values in nF, pF.

ESR Equivalent series resistance

ESL Equivalent series inductance

ESR (Equivalent series resistance) & ESL (Equivalent series inductance) Property of capacitors, function of temperature and frequency

the impedance of the capacitor decreases with higher temperature True

Step down only, Quiet, Regulator in parallel with load, Temperature drift (contains zener diode), Bigger losses than series-pass, No switching noice, its cheap Shunt regulator

Difference in efficiency between single linear voltage regulator and the same regulator but with rectifier diodes in before: A linear regulator simply dissipates the power that is not needed. With the rectifier diode before, a part of the dissipation will simply be moved to the diode instead. Therefore, if the supply and output voltage is the same for both configurations, there is no difference in efficiency. However, the regulator without rectifier diodes can be supplied with lower input voltage.

Series transistor controls the voltage drop over the regulator. High gain voltage error amplifier. Gets hot. Temperature controls the max current out. Innehåller en feedback-loop. Transistor kontrollerar spänningsfallet över regulatorn Series-pass regulator

Keeps the voltage constant by using an op-amp with a reference voltage and a feedback from the output. The op-amp acts as a comparator that will work towards keeping the voltage at the desired reference. “Extra” voltage will be burned away in the transistor and voltage divider. Linear series pass regulator

A comparator is a device that compares two voltages or currents and outputs a digital signal indicating which is larger. It has two analog input terminals V_+\, and V_-\, and one binary digital output V_o

SMPS SWITCHED MODE POWER SUPPLY

Duty cycle controls voltage out. On/off mode. “Noisy”. SMPS

In the hot loop, the emissions are the highest due to the big changes in current at high frequency In the other loop the current change is smaller.

The PWM frequency in the switcher will be near 50% but not exactly, why? At 100% efficiency, the switching would be 50%, but since we have losses in the system that need to be compensated, thus the “duty cycle” will be slightly higher.

It can (only) output a higher voltage. Rearranged forward-mode. The inductor always tries to keep the current level constant. when the switch is on, the inductor is allowed to charge up with current. When it switches off, the inductor attempts to keep its current level constant, thereby resulting in an increase in the voltage. Step up

When systems have to be galvanically isolated. Expensive and complex. Efficiency 70-84%. Possibly noisy. Buck-Boost

Something that converts energy from one type to another. In this course: sensor or actuator TRANSDUCER

Actuator 3 types of loads from actuators: resistive inductive capacitive (mostly combination of the three)

Light bulbs, heating elements. Resistive load

base, collector och emitter-portar bipolära transistorn

gate, drain och source MOSFET

har viss energidissipation, turn on delay time, turn off delay time, rise time and fall time. MOSFET

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