A Negative Resistance Device - IEEE

A Negative Resistance Device

Negative resistance where???



A change of terminology

A Perfect 100 W Power Supply

The Same 100 W Power Supply

Any Perfect Power Supply

High Line Impedance Issue

A Line Impedance Issue, CS101

A Line Impedance Issue, CS101

Stabilized Line Impedance

You might think you’re failing ….

A Seemingly Good Inverter

Overlap Effects (Bad!!!)

Don’t do it. Really!

How much heat can a heat sink sink when the metal gets bent?

Adding a thick block underneath the TO‐220 closes up the gap.

Power Factor

Power Factor for Sinusoidal Vin

The Power Factor Issue

An Issue With High Voltage

HV Resistor Damage

Distributed Capacitance

A Capacitive Ladder Network

In the extreme case:

Protecting an HV Divider

Treat These Things With Care!!

A Pretty Nice Design, Really

Kinda Messy Looking Data

Finding An Exponential Equation

The Equation Fits Pretty Well

Thermal Rise and Fall

A Mixed Blessing

Rdson Rises As Temp. Rises

Temp. Rise and Fall Before Fix

Temp. Rise and Fall After Fix

Plotting Some Alleged Data

Dirty Doings Were Afoot!!!

The D‐type Flip‐Flop Problem

Using an RC in the Q* to D Path

Making A 10 MHz Oscillator

One Motor, Two Line Voltages

Transient Protector Peril

From MIL‐STD‐704A

MIL‐STD‐704A Transients

Picking A Transient Protector

1N6284A Peak Power Equation

Finding The Value of “R”

For T = 0 to Tmax, Find Rmax

A Possibly Surprising Result

With Power Derating

Diode Protection Resistance

Measuring Loop Gain

Measuring Loop Gain

Transformer Coupling of “E test”

Power Supply Loop Gain

Isolation Barrier Circuit



Agilent 4395A Analyzer

Making The Transformer

Making The Transformer

Gain Measurement Set‐Up

Gain plot with 0 dBm

Gain plot with –3 dBm





The whole bunch of them.

Bias for the primary side.

The culprit zener!

The remedy

Stabilized gain and phase

Stabilized gain

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A Negative Resistance Device - IEEE

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