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Friday, November 15, 2019

FreeMat - Engineering Technical Computing

FreeMat is a free environment for rapid engineering and scientific prototyping and data processing. It is similar to commercial systems such as MATLAB from Mathworks, and IDL from Research Systems, but is Open Source. FreeMat is available under the GPL license.

FreeMat - Engineering Technical Computing

FreeMat - Engineering Technical Computing

FreeMat is chartered to go beyond MATLAB to include features such as a codeless interface to external C/C++/FORTRAN code, parallel/distributed algorithm development (via MPI), and advanced volume and 3D visualization capabilities.

Features Include
  • N-dimensional array manipulation (by default, N is limited to 6)
  • Built in arithmetic for manipulation of all supported data types.
  • Support for solving linear systems of equations via the divide operators.
  • 2D plotting and image display
  • Arbitrary-size FFT support
  • Pass-by-reference support (an IDL feature)
  • 3D Plotting and visualization via OpenGL

Tuesday, November 12, 2019

eCircuit Center - Spice Schematics

"The goal is a site where the learning of electronics is hands-on and fun. And the SPICE circuit simulator is a great software tool to achieve that goal. It hit me the first time I used SPICE - simulating is fun! And because it's easy to use, I've spent a lot of time building and exploring circuits." - Rick

eCircuit Center - Spice Schematics

SPICE is capable of performing both AC (frequency) Analysis and Transient (time) Analysis. SPICE also performs a number of other analyses like DC, Sensitivity, Noise and Distortion.

SPICE Basics, SPICE Commands, Circuit Collection

eCircuit Center - Spice Schematics

"At the core of the function generator is a triangle wave generator. How do you generate a triangle wave? The most common way is to get a capacitor and then alternate charging it and discharging it. But how to you get a nice linear ramp across the capacitor?"

Triangle and Square-Wave Generator

Simulation Circuit Examples -
  • Programmable Gain Amplifier (PGA) Op Amp
  • Single-Supply AC Inverting Amplifier
  • Instrumentation Amp (3 Op Amp)
  • Sensor Bridge with Current Bias
  • The PID Controller
  • Pulse Width Modulation
  • Precision Half-Wave Rectifier

Thursday, October 17, 2019

Berkeley Design Automation - Analog and RF SPICE

"Berkeley Design Automation (BDA) is the electronic design automation (EDA) industry leader in next-generation analog, RF, and mixed-signal integrated circuit (IC) verification."

Berkeley Design Automation - Analog and RF SPICE (wayback)

Berkeley Design Automation - Analog and RF SPICE

(Update - BDA now part of Mentor Graphics)

Analog FastSPICE is based on Precision Circuit Analysis technology. This technology is a proprietary combination of innovative applied mathematics and optimized numerical analysis.

Analog FastSPICE AFS  Mentor Graphics

The Analog FastSPICE (AFS) Platform is the world’s fastest nanometer circuit verification platform for analog, RF, mixed-signal, and custom digital circuits.

For silicon-accurate characterization it includes the industry's only comprehensive full-spectrum device noise analysis and a high-productivity Analog Characterization Environment.

Saturday, October 12, 2019

LM723 Power Electronics Workhorse

This is another versatile and flexible chip. I could design current sources, voltage to current transmitters, level translation and many more. You can think of applications beyond the Power Electronics Scope with this.

LM723 Power Electronics Workhorse

"The circuit provides internal current limiting. When the output current exceeds 150mA an external NPN or PNP pass element may be used. Provisions are made for adjustable current limiting and remote shutdown."

LM723 Power Electronics Workhorse

The LM723/LM723C is also useful in a wide range of other applications such as a shunt regulator, a current regulator or a temperature controller

Some Specs -

Input voltage up to 40V, Output voltage adjustable from 2 to 37V, Output current to 150mA without external pass transistor and Adjustable current limiting.

Reliability of Electronic Products

I have been in Product Design, Manufacturing and Marketing of Electronic Products/components. I have also been, like many of you, a customer.

It is very important that the customer gets a Reliable, Sturdy, Usable and Dependable product. This is what makes the Good Brands which in turn add to the Company Reputation and value.

Bathtub Curve - Wikipedia

The most important is the "Direct Customer Support" when a product fails or user finds it difficult to operate.  This include Prompt Product Service and Repairs. Any laxity or high-handedness or a Ping-Pong Customer Support can cause acute Brand Blindness that could even become Hereditary. Your brand can be shunned by a Family for generations and they also propagate negative marketing.

Reliability of Electronic Products

Your Product and Your Customer are like Family. Protect it and Nourish it for your own good.

- delabs 2015

The bathtub curve is widely used in reliability engineering. It describes a particular form of the hazard function which comprises three parts:
  • The first part is a decreasing failure rate, known as early failures.
  • The second part is a constant failure rate, known as random failures.
  • The third part is an increasing failure rate, known as wear-out failures.
  • The name is derived from the cross-sectional shape of a bathtub. 
ideas from Y2K refined in 2015

ideas of delabs - id1009