Reese Electronics on Westwood Blvd in Los Angeles. Helmut was a mechanical engineer for Olivetti.

The following document provides a step-by-step procedure to review Power over Ethernet designs for thePowered Device side of the cable, and the accompanying DCDC. The best advice is to find an EVM orreference design that most closely matches the design. For example, if the design is a 5-V output synchronousflyback with a 48-V adapter on the primary with the TPS23758, use the TPS23758EVM-080 to compare.Check every component and note the differences

DP83848VYB/YB HLQFP (48) 7.00 mm × 7.00 mmDP83848I/C LQFP (48)

The physicistsStephen Wolfram and Brosl Hasslacher introduced me, in the early1980s, to chaos theory and nonlinear systems. In the 1990s, I learnedabout complex systems from conversations with Danny Hillis, the bi-ologist Stuart Kauffman, the Nobel-laureate physicist Murray Gell-Mann, and others. Most recently, Hasslacher and the electrical engineerand device physicist Mark Reed have been giving me insight into the in-credible possibilities of molecular electronics.

I, O, P switches

Two main considerations determine how much capacitance you will need: the required holdup time and the allowable ripple voltage.

Benefits of Discretes IGBT are high current density and low power dissipation resulting in higher efficiency and smaller heat sink to allow lower overall system cost.

Features• VCE = 650 V• IC = 40 A• Powerful monolithic diode optimized for ZCS applications• High ruggedness, temperature stable behavior• Very low VCEsat and low Eoff• Easy paralleling capability due to positive temperature coefficient in VCEsat• Low EMI• Low electrical parameters depending (dependence) on temperature• Qualified according to JESD-022 for target applications• Pb-free lead plating; RoHS compliant• Complete product spectrum and PSpice Models: http://www.infineon.com/igbt/

Current Loop Feedback Configuration(Sizing of the Current Transformer Turns Ratio and Sense Resistor (RS)

Similar to other power management devices, whenlaying out the PCB it is important to use star grounding techniques and to keep filter and high frequency bypasscapacitors as close to device pins and ground as possible. To minimize the possibility of interference caused bymagnetic coupling from the boost inductor, the device should be located at least 1 inch away from the boostinductor. TI recommends the device not be placed underneath magnetic elements

The bridge rectifier must be rated to carry the full line current. The voltage rating of the bridge should be at least600 V. The bridge rectifier also carries the full inrush current as the bulk capacitor COUT charges when line isconnected.

Detailed Design Procedure

A resistor-divider network from VREF to GND can easily program the peak current limit voltage on PKLMT,provided the total current out of VREF is less than 2 mA to avoid drooping of the 6-V VREF voltage. TIrecommends a load of less than 0.5 mA, but if the resistance on PKLMT is very high, TI recommends a smallfilter capacitor on PKLMT to avoid operational problems in high-noise environments.

One of the main benefits from the 180° interleaving of phases is significant reductions in the high-frequencyripple components of both the input current and the current into the output capacitor of the PFC preregulator.Compared to that of a single-phase PFC stage of equal power, the reduced ripple on the input current eases theburden of filtering conducted-EMI noise and helps reduce the EMI filter and CIN sizes. Additionally, reduced high-frequency ripple current into the PFC output capacitor, COUT, helps to reduce its size and cost. Furthermore, withreduced ripple and average current in each phase, the boost inductor size can be smaller than in a single-phasedesign

The UCC28070 power factor corrector IC controls two CCM (Continuous Conduction Mode) Boost PFC powerstages operating 180° out of phase with each other. This interleaving action reduces the input and output ripplecurrents so that less EMI filtering is needed and allows operation at higher power levels than a non-interleavedsolution.

RSYN RSYNTH resistance 15 750 kΩRRDM RDM resistance 30 330 kΩ

Soft-Start and External Fault Interface. Connect a capacitor to GND on this pin to set the soft-start slew ratebased on an internally-fixed, 10-μA current source. The regulation reference voltage for VSENSE is clamped toVSS until VSS exceeds 3 V. Upon recovery from certain fault conditions, a 1-mA current source is present at theSS pin until the SS voltage equals the VSENSE voltage. Pulling the SS pin below 0.6 V immediately disablesboth GDA and GDB outputs.

THE PHASE-SHIFT FULL BRIDGE (PSFB) is a classic topology for applications that must accommodate a wide range of operating voltages, as with battery chargers. A PSFB converter generally uses four power switches (MOSFETs or IGBTs) to form a full bridge on the primary side of an isolation transformer.

Both the output charge and gate charge are ten times lowerthan with Si, and the reverse recovery charge is almost zero, which is key for high-frequency operations.

The complete switching waveforms are shown in the following figure.

From equation (1) we see that under light loading, IL1 is small, so that ZVS operation is not easily achieved, but as the load is increased ZVS operation is more easily realized.

As in the explanations of Modes (5) and (6) and Modes (12) and (13), in the lagging leg, if the amount of energy stored in LS is not greater than that stored in COSS for a MOSFET, the MOSFET charging and discharging are not completed, and so ZVS operation is not achieved.

Q2 turns on. At this time DQ2 is conducting, so the Q2 drain-source voltage VDS_Q2 is essentially zero. That is, ZVS operation is achieved, and so a turn-on loss does not occur

Below, operation and current paths for Modes (1) to (14) are described

Power dissipation due to OUTPUT slewing during FET turn ON in the recirculation path is given by:PSW3 [W] = (0.5 x VD x IL x VD / SRrise x fPWM) + (0.5 x VD x IL x VD / SRfall x fPWM), where, (4)i. fPWM = PWM switching frequency [Hz]ii. VD = FET body diode forward bias voltage [V]iii. IL = Load current [A]iv. SRrise = Output voltage slew rate during rise [V/sec]v. SRfall = Output voltage slew rate during fall [V/sec]This dissipation is typically not considered as it is quite insignificant.

Power dissipation due to the dead times between switching FETs is given by:PSW2 [W] = (VD x IL x tDEADrisex fPWM) + (VD x IL x tDEADfallx fPWM), where, (3)i. fPWM = PWM switching frequency [Hz]ii. VD = FET body diode forward bias voltage [V]iii. IL = Load current [A]iv. tDEADrise = dead time during rise [sec]v. tDEADfall = dead time during fall [sec]Dead times are necessary to mitigate any risk of current shoot through between the switching powerFETs. Integrated FET drivers often have a feedback based self timed FET switching sequence to ensurethe smallest possible dead times while avoiding any shoot through current.

Power dissipation from conduction loss of each FET due to its on-resistance is given by:PRON [W] = RON × IL2, where, (1)a. RON = FET on-resistance [ohm]b. IL = Load current [A]

Power dissipation due to output slewing during rising and falling edges is given by:PSW1 [W] = (0.5 x VM x IL x VM / SRrise x fPWM) + (0.5 x VM x IL x VM / SRfall x fPWM), where, (2)i. fPWM = PWM switching frequency [Hz]ii. VM = Supply voltage to the driver [V]iii. IL = Load current [A]iv. SRrise = Output voltage slew rate during rise [V/sec]v. SRfall = Output voltage slew rate during fall [V/sec]Output slewing rate is a balance between EM (Electro magnetic) performance and device powerdissipation.

Circuit Schematics

Here is an architecture diagram of the devices I’m currently using

Voltage is the pressure from an electrical circuit's power source that pushes charged electrons (current) through a conducting loop, enabling them to do work such as illuminating a light.

It's like these people walking on the bridge. They are all walking about the same speed, but there are so many more people jostling to cross at the top that the total "current" of bodies is large.

When current flows what actually happens is electrons hop from atom to atom in a kind of long chain, akin to a bucket brigade.

Voltage is the ability to overcome electrical resistance--to get more electrons to flow through a conductor, despite higher electrical resistance. For a loose analogy, think of a person pushing a heavy weight. Higher voltage is equivalent to a person who's stronger, so he can push a heavier weight. Being able to push a heavy weight doesn't necessarily mean he can run particularly fast.

Alloys[edit] Antimony forms a highly useful alloy with lead, increasing its hardness and mechanical strength. For most applications involving lead, varying amounts of antimony are used as alloying metal. In lead–acid batteries, this addition improves plate strength and charging characteristics.[49][59] For sailboats, lead keels are used as counterweights, ranging from 600 lbs to over 8000 lbs; to improve hardness and tensile strength of the lead keel, antimony is mixed with lead between 2% and 5% by volume. Antimony is used in antifriction alloys (such as Babbitt metal),[60] in bullets and lead shot, electrical cable sheathing, type metal (for example, for linotype printing machines[61]), solder (some "lead-free" solders contain 5% Sb),[62] in pewter,[63] and in hardening alloys with low tin content in the manufacturing of organ pipes. Other applications[edit] Three other applications consume nearly all the rest of the world's supply.[48] One application is as a stabilizer and catalyst for the production of polyethylene terephthalate.[48] Another is as a fining agent to remove microscopic bubbles in glass, mostly for TV screens;[64] antimony ions interact with oxygen, suppressing the tendency of the latter to form bubbles.[65] The third application is pigments.[48] Antimony is increasingly being used in semiconductors as a dopant in n-type silicon wafers[66] for diodes, infrared detectors, and Hall-effect devices. In the 1950s, the emitters and collectors of n-p-n alloy junction transistors were doped with tiny beads of a lead-antimony alloy.[67] Indium antimonide is used as a material for mid-infrared detectors.[68][69][70]

Made in China 2025, Beijing has designs to dominate cutting-edge technologies like advanced microchips, artificial intelligence and electric cars, among many others, in a decade

great place to start finding circuit schematic is the Discover Circuits site. They have a comprehensive list of fun circuits to experiment with

Step 19: Your Third Circuit

Step 18: Your Second Circuit

Step 17: Your First Circuit

designed to allow you to be able to insert an integrated circuit into the center

To use wire in your circuit, simply cut a piece to size, strip a 1/4" of insulation from each end of the wire and use it to connect points together on the breadboard

When things are wired in series, things are wired one after another, such that electricity has to pass through one thing, then the next thing, then the next, and so on

circuit is a complete and closed path through which electric current can flow

electricity is typically defined as having a voltage and a current rating

it is recommended that you use insulated 22awg (22 gauge) solid core wire

Wires are nice because they allow you to connect things without adding virtually no resistance to the circuit

there typically runs two continuous bus lines. One is intended as a power bus and the other is intended as a ground bus

They are covered with a grid of holes, which are split into electrically continuous rows. In the central part there are two columns of rows that are side-by-side

Breadboards are special boards for prototyping electronics

Batteries are represented in a circuit by a series of alternating lines of different length

battery is a container which converts chemical energy into electricity

This is dependent on the type of switch it is

switch is basically a mechanical device that creates a break in a circuit. When you activate the switch, it opens or closes the circuit

it is ideal to light up multiple LEDs by wiring them in parallel

Like all diodes, LEDs create a voltage drop in the circuit, but typically do not add much resistance

special type of diode that lights up when electricity passes through it. Like all diodes, the LED is polarized and electricity is only intended to pass through in one direction

For instance, if you have two 10K resistors in series between power (5V) and ground (0V), the point where these two resistors meet will be half the power supply (2.5V) because both of the resistors have identical values

current is rated in Amps

integrated circuit is an entire specialized circuit that has been miniaturized and fit onto one small chip with each leg of the chip connecting to a point within the circuit. These miniaturized circuits typically consist of components such as transistors, resistors, and diodes

PNP transistors allow electricity to pass from the emitter pin to the collector pin

NPN transistors allow electricity to pass from the collector pin to the emitter pin

transistor takes in a small electrical current at its base pin and amplifies it such that a much larger current can pass between its collector and emitter pins. The amount of current that passes between these two pins is proportional to the voltage being applied at the base pin

the other side connects to power

The ring found on one end of the diode indicates the side of the diode which connects to ground

Diodes are components which are polarized. They only allow electrical current to pass through them in one direction. This is useful in that it can be placed in a circuit to prevent electricity from flowing in the wrong direction

Ceramic disc capacitors are non-polarized, meaning that electricity can pass through them no matter how they are inserted in the circuit

Electrolytic capacitors are typically polarized. This means that one leg needs to be connected to the ground side of the circuit and the other leg must be connected to power. If it is connected backwards, it won't work correctly

capacitor is a component that stores electricity and then discharges it into the circuit when there is a drop in electricity

With alternating current, the direction electricity flows throughout the circuit is constantly reversing

resistors add resistance to the circuit and reduces the flow of electrical current. It is represented in a circuit diagram as a pointy squiggle with a value next to it

electricity in a circuit must be used

With Direct Current, electricity flows in one direction between power and ground

Potentiometers are measured in ohms like resistors, but rather than having color bands, they have their value rating written directly on them (i.e. "1M"). They are also marked with an "A" or a "B, " which indicated the type of response curve it has

Potentiometers are variable resistors. In plain English, they have some sort of knob or slider that you turn or push to change resistance in a circuit. If you have ever used a volume knob on a stereo or a sliding light dimmer, then you have used a potentiometer

The round notch on one edge of the IC chip indicates the top of the chip. The pin to the top left of the chip is considered pin 1. From pin 1, you read sequentially down the side until you reach the bottom (i.e. pin 1, pin 2, pin 3..). Once at the bottom, you move across to the opposite side

As a beginner, you will be mainly working with DIP chips. These have pins for through-hole mounting. As you get more advanced, you may consider SMT chips which are surface mount soldered to one side of a circuit board

you can learn all about integrated circuits by looking up their datasheets. On the datasheet you will learn the functionality of each pin. It should also state the voltage and current ratings of both the chip itself and each individual pin

There are two basic types of transistors, which are NPN and PNP

They are represented in schematic as a line with a triangle pointing at it

it requires energy to pass through a diode and this results in a drop of voltage. This is typically a loss of about 0.7V

The most commonly encountered types of capacitors are ceramic disc capacitors that look like tiny M&Ms with two wires sticking out of them and electrolytic capacitors that look more like small cylindrical tubes with two wires coming out the bottom (or sometimes each end)

Capacitors are measured in Farads

Any resistor of over 1000 ohms is typically shorted using the letter K. For instance, 1,000 would be 1K

Anyhow... a resistor with the markings brown, black, orange, gold will translate as follows: 1 (brown) 0 (black) x 1,000 = 10,000 with a tolerance of +/- 5%

You read the values from left to right towards the (typically) gold band

two different ways in which you can wire things together called series and parallel

switch does not add any resistance to a circuit and simply adding a switch between power and ground will create a short circuit

Always make sure that you never accidentally connect positive voltage to ground while wiring things in parallel

electricity always follows the path of least resistance to ground

It is very important to prevent short circuits by making sure that the positive voltage is never wired directly to ground

Shorts are bad because they will result in your battery and/or circuit overheating, breaking, catching on fire, and/or exploding

there needs to be something wired between positive and ground that adds resistance to the flow of electricity and uses it up. If positive voltage is connected directly to ground and does not first pass through something that adds resistance, like a motor, this will result in a short circuit

Voltage is obviously rated in Volts

There are two types of electrical  signals , those being alternating current (AC), and direct current (DC)

The rate of reversal is measured in Hertz, which is the number of reversals per second

Figure 3: Motor system with flip switch and potentiometer

“The current measures are not an acceptable long-term solution to whatever threat they are trying to mitigate. Even in the short term it is difficult to understand their effectiveness. And the commercial distortions they create are severe,” said IATA director general Alexandre de Juniac.