Search This Blog

Thursday, September 05, 2019

Accelerometers in Electronics

An accelerometer is a device that measures non-gravitational accelerations. These are accelerations produced by mechanically accelerating the accelerometer via its casing. Accelerometers can be used to measure vehicle acceleration.

Accelerometers can be used to measure vibration on cars, machines, buildings, process control systems and safety installations. They can also be used to measure seismic activity, inclination, machine vibration, dynamic distance and speed with or without the influence of gravity. - Accelerometer Wikipedia

Accelerometers in Electronics

MMA7260Q is a 3-axis accelerometer  from Freescale Semiconductor. This accelerometer can be used with an extension Library Mma7260q which simplifies some initialization values and tilt detection.

ADXL105 Lower-Noise Wider-Bandwidth Accelerometer - The ADXL105, a near-ideal kind of vibration sensor, eliminates significant problems with existing vibration sensors, such as piezoelectric and bulk capacitive sensors. Primary benefits derive from much lower cost, stable sensitivity as a function of frequency and temperature, ruggedness, and ease of use. Besides machine health and condition monitoring, it is particularly well suited for noise and vibration cancellation applications.

A beginner's guide to accelerometers - By measuring the amount of static acceleration due to gravity, you can find out the angle the device is tilted at with respect to the earth. By sensing the amount of dynamic acceleration, you can analyze the way the device is moving.

Society of Robots' tilt to servo control app - How does it work? Inside an accelerator MEMS device are tiny micro-structures that bend due to momentum and gravity. When it experiences any form of acceleration, these tiny structures bend by an equivelent amount which can be electrically detected

David T.'s motor balancing experiments - Using an oscilloscope to measure AC vibration signals generated by an accelerometer (from Dimension Engineering).

Monday, September 02, 2019

Embedded Systems Design

An Embedded Microcontroller or DSP system is made of Chips, Circuits and Firmware. The digital voltage levels, speed, bus width, fan out, power consumption are some factors that a designer has to keep in mind. As portable and wireless gadgets are becoming more popular, RF, Ethernet and Energy Efficient Design aspects should be studied. Power electronics and Analog Circuits knowledge is used around the system, all this is integrated to make an instrument, equipment or gadget.

Microcontrollers are digital chips that derive their intelligence from the firmware program that a user loads into it. Tiny Logic and Math elements simulate Digital Logic according to the programmed instruction to obtain a desired result. Having an equivalent math or logic circuit for the same result would take enormous space, cost and effort. I cover this subject in Embedded Systems

Embedded Systems Design

Microprocessors and Microcontrollers

Analog devices like transistors and diodes lead to opamps and analog computing. This takes more parts but with fast devices can be real time. Then came Logic and Digital Circuits, here also big systems will take too many parts. A very Old hp Logic Analyzer instrument, could be HP1600A, had more than five large PCBs, Toggle Switches and numerous 74Fxx TTL Chips. I tried to revive it, it could not be fully restored.

Microcontroller - 8051, 8052, OpCodes, Analog and PC Interface.

Then came the solution the Microprocessor. Here the entire system goes into the firmware and a Hardware Tool Set in the Microprocessor made up of Logic and Math is sequentially used to perform the same operation that would require innumerable Gates in a plain hardware digital circuit. But as it performs the operations one after another, it takes time and is defined by the CPU Clock Speed.

When the External RAM and EPROM and other peripheral devices moved into the main package, MicroController were born. When more external devices merged with the MicroController. It formed a nearly complete computer, this is known as the SOC.

Protect your Design or IP

If you have made an electronic product with a new circuit or code and need to protect it, then these are some Methods. If your Intellectual Property is an Idea, A Hardware Innovation or Software Application; It may need some protection other than patents. Sometimes patents are used for general applications and generic designs. Patent only an Original Idea or Innovation or an Exclusive and Unique Method.

Microcomputer Circuits in Process Control.

Protect your Design or IP

If you are small and the innovation very big, tie up with established companies with reputed brands. If you are a source for a certain product component or module, make certain restriction on patenting products made from it. Else, your Module or Application Sales may be jammed by Panic Patents.

That is the reason, the Platform that fosters innovation is Open Source.

Monday, August 05, 2019

7800 and 7900 Series Voltage Regulators

The LM78XX series of three-terminal positive regulators is available in the TO-220 package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut-down, and safe operating area protection.

7805 is popular for Embedded Systems and 7905 is sometimes used for the Dual Supply needs in such Microcontroller cards with Mixed Design sub-sections like A/D or Opamps.

7812 and 7912 are very popular in powering Traditional Opamp or communications circuits with a stable and reliable Dual Supply.

Power Supplies Section - Here you will find examples of 7824 and 7924 Power supplies.

Fairchild LM7812

In Instrumentation and Industrial Circuits where Size is not a problem and the current or power usage is less. A Mains transformer, bridge regulators, capacitors and these regulators are a time tested low noise and robust system.

SMPS does have EMI-RFI problems, hence use when small sizes are needed and high currents are required. In battery powered devices switching supplies are inevitable as they are power efficient.

Saturday, August 03, 2019

Electrical Safety and Clean Power

This is an educative and important guide for Electrical Equipment Safety. This can be also applied partially to Power Electronics and Home Energy Systems. Electronic Equipment also have to be maintained by Calibrating them and protecting them from environmental parameters like dust, grime, direct sunlight, moisture, humidity, sea wind (brine), corrosive fumes and chemicals. They should not be even placed near machines like a big lathe, sub-sonic or low frequency vibrations.

Electrical Safety Testing Reference Guide

Electrical Safety is a Serious Issue Electrical Safety in the workplace is the most important job of an electrical worker. No matter how much training one has received or how much employers try to safeguard their workers, Electrical Safety is ultimately the responsibility of the electrical worker.

Electrical Safety and Clean Power

Electrical Safety Hazards Handbook

Power Studies, Arc-Flash Hazard Labeling, Data Gathering and Inspection, Engineering Services.

The steps to osha electrical safety

Electrical Design, Lighting and most important Earthing or Grounding. Good Reference Articles and Product Reviews.