Saturday, March 18, 2017

SpecScope from NFX Development

This is an interesting attempt in the right direction. The bandwidth may be only the audio range, but the first instruments with touch interface for tablets are being built for tablets even by DIY Enthusiasts.

SpecScope from NFX Development

SpecScope is a spectrum analyzer and is the second in the line of engineer applications from NFX Development. The SpecScope incorporates the speed and ease of use to access FFT frequency measurements in a hurry.

SpecScope from NFX Development

Some of the Features
  • Logarithmic/Linear measurements
  • Pinch to zoom in both X and Y axis
  • Selectable No. bin for accuracy versus speed
  • Three settings of spectrum averaging
  • Threshold trigger to hold the peak value
  • Tap to pause and resume measurements (graph is still navigational in this mode)
  • A adjustable sample rate allow analysis from 10 Hz to 22KHz

Thursday, March 16, 2017

Microdesigns - Microcomputer System Development

Microdesigns, Inc. is an Engineering and manufacturing services company specializing in microcomputer and electronic systems.They design both board- and box-level products, software and industrial systems.

Microdesigns - Microcomputer System Development

Shown on the right is a SBX board providing two independent RS-232C or RS-422A/449 serial ports with individually programmable baud rates; a battery-maintained clock/calendar with programmable periodic, time-of-day alarm and power fail interrupts; and 8K, 32K or 128K bytes of battery-maintained CMOS RAM.

QwikFlash Development Kits -  QwikFlash board with accessories and optionally an expansion board and stand.

QwikFlash Development Kits

The QwikFlash board developed by Dr. Peatman and his Georgia Tech students is a compact microcontroller demonstration board with on-board resources that are found in many real-world applications. MICRODESIGNS offers QwikFlash as a fully assembled and tested board assembly with a programmed microcontroller. 

Microdesigns, Inc.
1979 S. Bibb Dr. Tucker, GA  30084, USA

Wednesday, March 01, 2017

The MOSFET in Power Electronics

delabs Notes - In a Circuit Module, if all Power and Signal Polarities are reversed. All NPN to PNP, All N-Channel to P-Channel and Vice Versa. All Diodes and Caps too turned around. This Topsy Turvy or Mirror Design ought to work in Theory. It has worked for some circuits in practice too in my experience. ?

Some believe that N-Channel is more Robust than the P Type. In Bipolar Transistor NPN is more trusted for the final output stages. The NPN Transistor and N-Channel turn-on by a Positive control bias. It may be inappropriate to say this mosfet is NPN or PNP.

The MOSFET in Power Electronics

The traditional metal–oxide–semiconductor (MOS) structure is obtained by growing a layer of silicon dioxide (SiO2) on top of a silicon substrate and depositing a layer of metal or polycrystalline silicon (the latter is commonly used). As the silicon dioxide is a dielectric material, its structure is equivalent to a planar capacitor, with one of the electrodes replaced by a semiconductor.

If the MOSFET is an n-channel or nMOS FET, then the source and drain are "n+" regions and the body is a "p" region. If the MOSFET is a p-channel or pMOS FET, then the source and drain are "p+" regions and the body is a "n" region. The source is so named because it is the source of the charge carriers (electrons for n-channel, holes for p-channel) that flow through the channel; similarly, the drain is where the charge carriers leave the channel. MOSFET - Wikipedia

This application note discusses the breakdown voltage, on-resistance, transconductance, threshold voltage, diode forward voltage, power dissipation, dynamic characteristics, gate charge and dV/dt capability of the power MOSFET.
Application Note AN-1084 Power MOSFET Basics - IRF

A MOSFET is a transistor. It is a Metal Oxide Field Effect Transistor. Here are the symbols for FETs and MOSFETs: The MOSFET How the MOSFET works

The conductivity of the path from Source to drain is controlled by applying a voltage between the gate and the body of the semiconductor. N-channel enhancement MOSFET

See this simple circuit that explains everything
n-channel MOSFET switch - George Watson, Univ. of Delaware, 1996.