Electrical and Computer Engineering 1 EEL3923C Design 1 Erin Patrick, Michael Stapleton Electrical and Computer Engineering Power Supply Module Electrical and Computer Engineering 3 Source: “Amplifier Selection Guide,” Texas Instruments, 1Q 2003 Sensor/ Instrument Information System Output Power Management Block Diagram of Generic Electronic System Electrical and Computer Engineering Power Converter Types § AC to DC Converter (Rectifier) – one of the most popular/used power converters § DC to AC Converter (Inverter) – converts sorted energy from battery banks to loads needing continuous/AC § AC Voltage Regulator – converts AC power at one voltage level to another § DC to DC Converter (Chopper) § Boost converter – steps up the DC voltage § Buck Converter – steps down the DC voltage § Buck - Boost Converter – can do both conversions § AC/DC Converter – can do both inverting and rectifying § Frequency Converter – changes frequency of AC power (e.g., from 50 Hz to 60 Hz) § Phase Converter – converts single phase to 3 phase, or 3 phase to single phase 4 Source: https:// www.electricalengineering.xyz /power - electronics/10 - types - of - power - electronics - converters/# AC_to_DC_Converter_Rectifier Electrical and Computer Engineering What needs power conversion/management? 5 Source: “Fundamental of Power Electronics,” Erickson and Maksimovic LCD Backlight https://computer.howstuffworks.com/qu estion580.htm Electrical and Computer Engineering What needs power conversion/management? 6 Source: “Fundamental of Power Electronics,” Erickson and Maksimovic Electrical and Computer Engineering What needs power conversion/management? 7 Source: “Fundamental of Power Electronics,” Erickson and Maksimovic Electrical and Computer Engineering Power Converter Considerations 8 Source: “Fundamental of Power Electronics,” Erickson and Maksimovic • Power converter circuits need to be efficient • Designers try to limit the circuit elements to passive elements and solid - state devices (diodes, BJTs, MOSFETs) Electrical and Computer Engineering AC to DC Converter: Typical Rectifier Circuit Stages 9 Source: “Circuit Analysis and Design”, Ulaby , Maharbiz and Furse, p. 432 Electrical and Computer Engineering The Transformer 10 • Transformer for this module is supplied in the lab • Used to step down the wall voltage to a lower value that is more manageable to convert to ~5V DC Electrical and Computer Engineering The Transformer 11 How to build a transformer circuit in LTSpice • Use two inductors with inductance values such that: 𝑣 ! = " ! " " 𝑣 # = $ ! $ " 𝑣 # • Then make them mutually coupled by inserting a Spice directive on the schematic as such: K1 L1 L2 1 • This makes the coupling coefficient K1 = 1 • Dots will appear at the coupled inductors • On the primary side, a small series resistance will also have to be included to allow Spice to solve. You can include a series resistance in the inductor model itself or a place a resistor in the circuit. • Remember that the wall voltage is 120 Vrms (not peak) at 60 Hz This circuit shows an example of a voltage step - up by a factor of 3 in the secondary winding. Electrical and Computer Engineering Rectification Stage 12 Rectification Modes Your assignment: Find/design circuit implementation for full wave rectification. Good source: “Circuit Analysis and Design”, Ulaby , Maharbiz and Furse p. 432 - 437 Electrical and Computer Engineering Rectifier Diodes 13 Electrical and Computer Engineering Rectifier Diodes: LTSpice Model § Add 1N4004 diode model to LTSPICE diode model library – Navigate to C: \ Program Files \ LTC \ LTspiceIV \ lib \ cmp – Open standard.dio using notepad or by double - clicking and using LTSPICE – Insert the following into the file .MODEL 1N4004 D(IS = 3.699E - 09 RS = 1.756E - 02 N = 1.774 XTI = 3.0 EG = 1.110 CJO = 1.732E - 11 M = 0.3353 VJ = 0.3905 FC = 0.5 ISR = 6.665E - 10 NR = 2.103 BV = 400 IBV = 1.0E - 03 Iave =1000m Vpk =400 mfg =Fairchild type=silicon) – Close and restart LTSPICE • Insert a generic diode into your schematic • Right - click the diode; you should see a dialog box – Click ‘Pick New Diode’ – Select 1N4004 from the list of possible diodes – The diode should now look like: 14 Electrical and Computer Engineering Filter Stage: Capacitor Types 15 Ref: https:// www.electronics - notes.com /articles/ electronic_com ponents /capacitors/capacitor - types.php Check the following source for guidance in choosing cap values: “Circuit Analysis and Design”, Ulaby , Maharbiz and Furse p. 432 - 437 Electrical and Computer Engineering Filter Stage: Capacitor Types - Application 16 Ref: https:// www.electronics - notes.com /articles/ electronic_com ponents /capacitors/capacitor - types.php Electrical and Computer Engineering Voltage Regulators: Zener Diode 17 Source: https:// www.digikey.com / en /maker/blogs/ zener - diode - basic - operation - and - applications • When reverse biased, the Zener diode will establish a constant voltage drop across it, within a reverse bias current range of I min - I max + - Electrical and Computer Engineering Voltage Regulator: 1N4733A Zener Diode 18 Electrical and Computer Engineering Zener Diode LTSpice Model § Add 1N4733A zener diode model to LTSPICE diode model library – Navigate to C: \ Program Files \ LTC \ LTspiceIV \ lib \ cmp – Open standard.dio using notepad or by double - clicking and using LTSPICE – Insert the following into the file * 1N4733 * Motorola 5.1V 1W Si Zener pkg:DO - 41 1,2 .MODEL 1N4733 D(IS=7.03E - 16 RS=0.871 TT=5.01E - 8 CJO=1.89E - 10 VJ=0.75 M=0.33 BV=5.059 IBV=0.049 Vpk =5.1 mfg =Fairchild type= zener ) – Close and restart LTSPICE • Insert a generic diode into your schematic • Right - click the diode; you should see a dialog box – Click ‘Pick New Diode’ – Select 1N4733 zener diode from the list of possible diodes – The zener diode should now look like 19 Electrical and Computer Engineering Voltage Regulators: ICs § A voltage regulator is a circuit that creates and maintains a fixed output voltage, irrespective of changes to the input voltage or load conditions. § There are two main types of voltage regulators: linear and switching. § linear regulators operate with low efficiency § switching regulators operate with high efficiency 20 Example: Liner Regulator Example: Switching Regulator *One of the main disadvantages for linear regulators is that they can be inefficient, as they dissipate large amounts of power in certain use cases. The voltage drop of a linear regulator is comparable to a voltage drop across a resistor. Source: https:// www.monolithicpower.com / en /voltage - regulator - types