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.

Tuesday, February 07, 2017

Reliability in Axial and Radial Plastic Capacitors

The Axial capacitors like Metalized Polypropylene MPP are more reliable in comparison of their radial counterparts of same voltage rating.

Also note 440V AC Continuous rating reads and translates differently than 630V DC Max. Overrating is an important step in reliability for engineers.

High Energy Circuits

Radial plastic caps, in mass production, due to various inconsistencies in production or quality measurement, are not recommended for high voltage unless its is a Manufacturer known for long term reliability and quality track record.

Reliability in Axial and Radial Plastic Capacitors

The radial caps when being wound, stretches the film/dielectric or weakens the dielectric at some areas as the turn is sharp, top/bot. This is possible unless the winding machine relaxes strain around the turns. In a Axial that may not be a problem as the film has more uniform stretch. The other reason  could be that the Film is wrapped a little on corners or compressed on epoxy impregnation. It could also be low quality non-uniform PP material.

Power Electronics & Solar Energy

Components Manufacturers have to spruce up a Raw-Material and Component Quality, not by red-tape but by actually improving the manufacturing and procurement processes, as the quantities involved are huge.

Monday, February 06, 2017

Induction Heating - Cooker Project

Single plate induction cooker demonstration board  Uses ST7LITE09 and STGW40NC60WD (40 A, W series).

The design is entirely controlled by a simple ST7FLITE09Y0 8-bit microcontroller, which  provides the PWM driving signals, communicates information to the user interface, and  drives the fan and relay control to the plate feedback.

With Single Voltage Flash Memory, Data Eeprom, Adc, Timers, Spi Active - ST7LITE09Y0 8-Bit Mcu

Induction Heating - Cooker Project

A single plate induction cooker with the ST7FLITE09Y0  PDF - Excerpt From Application Note above AN2383 Application note -

Put simply, an induction cooking element (what on a gas stove would be called a "burner") is a special kind of transformer. When a good-sized piece of magnetically conducting material such as, for example, a cast-iron frying pan, is placed in the magnetic field created by the cooking element, the field transfers ("induces") energy into the metal. That transferred energy causes the metal - the cooking vessel - to become hot.

By controlling the intensity of the magnetic field, we can control the amount of heat being generated in the cooking vessel and we can change that amount instantaneously.

Induction cooking functions based on the principle of the series L-C resonant circuit, where the inductance L is the cooking element itself. By changing the switching frequency of the high voltage half-bridge driver, the alternating current flowing through the cooking element changes its value. The intensity of the magnetic field and therefore the heating energy can be controlled this way.

Induction Cooker - STMicro AN2383

The +325 V DC link voltage is applied through a filter to the upper-side IGBT only when the safety relay is closed and the system is on. Components inside the dotted rectangle are the core part of the power stage: the L-C resonant tank is obtained by the plate (represented in the schematic by a spiral) and the capacitors on the left side. The resonant capacitor has been divided in two identical capacitors, so that the amount of current flowing through each capacitor is reduced by half, while the voltage to the capacitors remains the same.

Induction heating is a non-contact heating process - Richie's Tesla Coil Web Page

Thursday, February 02, 2017

Ricoh Electronic Devices - Smart Energy

Design and Manufacture semiconductor electronic devices, specialized design service for electronic devices and manufacturing service for such products.

Ricoh Electronic Devices - Smart Energy

Product line include - Power Management ICs, Real-time clock ICs, PC Interface and Communication LSI / Image Processing LSI.

Power Management ICs - DC/DC Converters, Battery Management, Watchdog Timer(W.D.T.) and Voltage Regulators.

The R1218x Series are PWM control type step-up DC/DC converter ICs with low supply current. It is fully dedicated to drive White LED with constant current.

R1218x Series - RICOH

Constant current can be set with an external resistance value. Dimming control is possible by PWM signal for CE pin. Feedback voltage is 0.2V, therefore power loss by current setting resistor is small and efficiency is good.

Ricoh Electronic Devices Company, Ltd.
13-1 Himemuro-cho, Ikeda City, Osaka 563-8501, JAPAN

Monday, January 16, 2017

Microsemi Corporation - High Performance Devices

Products  Microsemi Designs and Manufactures include high-performance, radiation-hardened and highly reliable analog mixed-signal integrated circuits, FPGAs, SoCs and ASICs; power management products; timing and voice processing devices; RF solutions; etc.

Microsemi Corporation - High Performance Devices

Zarlink and Actel are now part of  Microsemi. Actel have designed  SoCs and FPGAs based on flash and antifuse technologies.

Microsemi SmartFusion2 Starter Kit

Microsemi's SmartFusion2 Starter Kit

The SmartFusion2 starter kit supports industry-standard interfaces including Ethernet, USB, SPI, I2C and UART and includes a comprehensive breadboard to support unique design requirements.

"SmartFusion2 system-on-chip (SoC) FPGAs, which integrate inherently reliable flash-based FPGA fabric, a 166 MHz ARM Cortex-M3 processor, advanced security processing accelerators, DSP blocks, SRAM, eNVM...."

They also provide High-performance IP Cores for other designers and chip developers.

Microsemi Corporation
One Enterprise Aliso Viejo, CA 92656 USA