Wednesday, August 31, 2016

ESD circuit tutorial and PCB design guidelines for withstanding ESD (static discharges).

Radio-Electronics blog recently had an item on electrostatic design principles.

I remember that being a challenge during my electronics design years at a medical analyzer company - the sensitive electrometer had to withstand a 15kV shock.  And it did with a circuit identical to that mentioned below and in the article.  The trick is to choose the right components, however!

"The need for ESD protection and design guidelines for ESD for electronics devices and electronics assemblies has never been greater. With the geometries within integrated circuits becoming much smaller, they have become much more susceptible to damage from ESD. In addition to this other components like capacitors and resistors that were traditionally not treated as static sensitive devices, SSDs have now become so small that they also need to be treated in the same way.
While manufacture, repair, servicing and maintenance need to be undertaken in a static free environment, part of the ESD protection can be incorporated into the design of the electronics equipment. Implementing ESD design guidelines into the circuits themselves will help make them more robust. Not only will this help during the manufacturing stages when sub-assemblies are exposed to any static that may be in the environment, but when in use, equipment must be able to withstand the levels of static that appear in everyday life.

ESD protection requirement

With electronics devices used in today's electronics equipment being susceptible to electrostatic discharge, it is necessary to employ ESD design guidelines that ensure that devices used will be protected against its effects. The ESD design guidelines and the protection used is of particular importance where any connections are on the periphery of the equipment and may be accessed via the user.
When accessing external ports, users will not take any precautions against ESD, if they even understand about it. Therefore it is necessary to provide full protection for any external ports that may exist.
Electronics devices manufactured today are often required to survive a discharge of 8kV contact discharge (i.e. where the 8 kV is discharged directly onto the pin via a metallic contact) or a 15 kV air discharge (where the 15 kV point is close to the pin and discharges across an air gap). While this is the aim, not all devices will survive this and in many cases the discharge may be greater than this. It is therefore wise to add additional protection.

ESD design methods

The key to the ESD design guidelines for protecting the devices on any external Input / Output (I / O) lines, is to prevent the voltage rising above a level that will damage the interface device. This may be achieved using a circuit that clamps the maximum voltages to just outside the maximum operating extremes. Typically this may be just above the rail voltage and just below the zero volt line.
A typical circuit that can be used for clamping voltages employs reverse biased diodes from the input line to the voltage rail and to ground. This ESD protection circuit must ensure that the voltage excursions on the input line are limited. The diodes must also have a low level of residual current, and the capacitance must be low to ensure that the frequency response / data rate and other input parameters are not impaired.
Diodes used for ESD protection
Diodes used for ESD protection
The operation of the circuit is very simple in that the diodes, D1 and D2 are reverse biased under normal operating conditions. However if a pulse occurs that raises the input voltage above the rail voltage the top diode, D1, will conduct. Similarly if the voltage falls below the ground voltage, the other diode, D2, will conduct. Using ordinary signal diodes, the maximum voltage excursions that might expected on the input line in the first analysis may be +0.5V above the rail and -0.5V below ground. However this is not always the case as seen below...."
See more here:

Tuesday, August 30, 2016

EEVblog #892 “Siglent SSA3021X Spectrum Analyzer Teardown”

In a recent edition, the ever-effervescent and over-excited Australian Dave Jones takes a very detailed look inside the new Siglent SSA3021X 2GHz Spectrum Analyzer.

How does a spectrum analyzer front end work?

The entire RF section is broken down and analyzed in depth with a block diagram overlay and signal flow.

More than 36,000 people have viewed this video so it must be informative!!

See it here:  

Monday, August 29, 2016

September Newsletter: Saelig News: See How a Customer Saved $40,000 in 2 Days :)

Greetings Saelig Colleague,
I hope you managed to take some time off from busy schedules to relax and enjoy some down-time with family and friends. Summer is a time to recharge the batteries, pursue sports, and visit places you've never seen. But for many school starts again too quickly! Thinking of schools, if you know anyone enrolling in an electronics course, please remind them of our bargain-priced test equipment so they can work on their projects at home too!  

I trust you find our newsletter useful and interesting; your suggestions and comments are always welcome.  One reader wrote (thank you M): "I always look at your newsletter. I'm fascinated to see what an eclectic mix of products you have!" 

Here's what's new in the Saelig world to keep you up to date with products that may make your engineering life easier and "happy, prosperous, and blessed!"

New Rigol DS4000E Series 4-Channel Economy Oscilloscopes
Rigol DS4000E These are lower cost variants of the  Rigol DS4000 series with slightly reduced specifications. The E "Economy" versions are available as 100 or 200MHz 4-channel oscilloscopes at a very attractive price and meet the market demand for an affordable 4-channel oscilloscope with a 2GS/s sample rate on each channel. 

PicoScope Automotive Diagnostic Kits Now Available in Foam Trays to Fit Tool Chests
Foam TrayPico Technology's ubiquitousAutomotive Test Kits, previously only available in robust carry cases, are now available in foam storage trays that are designed to fit the tool chests commonly used in automotive repair centers.   Many technicians do not need to travel with their Pico Automotive Kits but need quick access to them, along with all the other diagnostic and mechanical tools in their arsenal. This new sturdy foam storage solution provides a convenient method to house each element of a Pico diagnostic kit (oscilloscope, leads, cables, pressure gauge, etc.) in the same cabinet as the technician's other familiar equipment.

New Economical 4 ½ Digit Benchtop Multimeter
Siglent SDM3045XThe Siglent SDM3045X is a 4½ digit dual-display digital multimeter that is suited to high-precision, multifunction, and automation measurement applications. It features a combination of basic measurement functions, with multiple math and display choices, and special features including histogram, trend chart, bar chart, statistics, hold measurement, dBm, etc.  Reading at up to 150 readings/second, the SDM3045X DMM will make measurements of True-RMS AC Voltage and AC Current, resistance to 100Mohms, capacitance to 10,000 microfarads, continuity and diode tests, frequency and period measurements, and temperature, with support for thermocouple and RTD sensors. With 1GB of Flash memory for storage of configuration and data files, it also supports USB external storage. Siglent's EasySDM software, provided free, allows for easy PC connectivity, external control and display.


New 3.2GHz Spectrum Analyzer from Rigol
DSA832E Spectrum AnalyzerThe Rigol DSA832E Spectrum Analyzer is a high performance, economical, and compact 9kHz to 3.2GHz Spectrum Analyzer.  A tracking generator function available in the DSA832E-TGmodel.  Digital I.F. circuitry guarantees reliability and performance for demanding RF applications. The rugged but very affordable DSA832ESpectrum Analyzer has a broad set of features and specs, including a large 8" WVGA color LCD and intuitive front panel controls.  Available options include a preamplifier for very small signals, a VSWR measurement toolkit for configuring and evaluating antennas, and an advanced measurement kit that enables additional functions such as channel boundaries and signal-to-noise ratio measurements.  The very useful EMI Pre-compliance Test Software helps to quickly locate product problems, enabling them to pass subsequent formal EMC testing.

Telemakus  0.1 to 6GHz Digital Attenuator Simulates Signal Fading
Telemakus TEA6000-95The TEA6000-95 0.1 to 6GHz RF Digital Attenuator is a USB-connected RF attenuator that is easily controlled by a Windows or Linux PC using the simple GUI provided. It operates over a 0.1 to 6GHz frequency range and can reduce input signal amplitudes by up to 95dB in 0.5dB steps.  With a power rating of +23dBm and a maximum switching speed of 1usecond, the TEA6000-95 RF Digital Attenuator operates as a programmable signal attenuator for simulating fading or for limit testing.
Simple GUIIt features excellent solid-state repeatability and performance, and the output signal is uninterrupted when changing attenuation values. The Windows version of the API is .NET based, making it compatible with many programming languages including VB.NET, C++, C#, LabView, Agilent VEE, and MATLAB, etc.

Versatile 1-Ch & 2-Ch 25/50MHz True Pulse Generators 
Aim-TTi TGP3100Using all digital techniques, the Aim-TTi TGP3100 series surpasses the capabilities of traditional pulse generators while adding features such as multiple pulse modulations. They can generate precision pulses from 1MHz up to 50MHz with pulse width and delay resolutions of 100psec. Single and dual channel models are available, both featuring large graphic LCDs for simultaneous text and waveform information.  The TGP3100 series features independently variable rise and fall times that can be set from 5nsec to 800 seconds. PWM and PDM (pulse width and pulse delay modulation) are incorporated. Unlike many other pulse generators, the TGP3100 series can perform linear and logarithmic sweeps of all waveform types, as well as extensive internal/external modulation of all waveforms (e.g. AM, FM, PM, SUM, FSK and BPSK etc.), double pulse, and user-defined pulse patterns.


New Mil-Spec High Reliability Crystal Oscillators
Euroquartz EQXO-x000BMKTwo new ranges of military specification crystal oscillators from Euroquartz are designed for use in applications that demand high reliability and tight tolerance. Available in industry standard dual-in-line packages, the new EQXO-1000BMK and EQXO-3000BMKclock oscillators feature a custom-designed quartz crystal and a CMOS/TTL compatible hybrid circuit mounted on a ceramic substrate. Manufactured using the latest advances in production technology, these oscillators achieve tight frequency calibration tolerance and high stability over a wide temperature range. The frequency range available is from 200kHz to 200MHz, with a calibration tolerance of ±30ppm at 25°C and a frequency tolerance of ±100 to ±50ppm over the full military temperature range from -55 to +125°C (±100 to ±30ppm over industrial temperature range from -40 to +85°C).


ABI PCB Test Equipment Paid for Itself in 2 Days! 
ABI PCB Test EquipmentOur Tech Trainer recently returned from a field trip to Arizona, where a large semiconductor company has installed its second BoardMaster system.  While he was there for a couple of days, they repaired a $40,000 circuit board and thus quickly saved the company lots of money!

Saelig Buy More Button

Focus on PicoScope 3000 Series PC Oscilloscopes and MSOs
PicoScope 3000 SeriesPicoScope 3000 Series USB Oscilloscopes and MSOs offer portable power with performance.  They are compact tools for electronics work that easily slip in a laptop bag or briefcase, so you can take high-performance equipment with you anywhere.  The range includes 2 or 4 analog channels as well as a built-in versatile function/arbitrary waveform generator (AWG). The MSO versions add 16 digital channels for debug purposes.

This table lists the PicoScope models available:

2-Channel MSO3203D MSO3204D MSO3205D MSO3206D MSO
4-Channel MSO3403D MSO3404D MSO3405D MSO3406D MSO

Key performance specs: up to 200MHz analog bandwidth; 1GSa/s real-time sampling; up to 512MSa buffer; 100k waveforms per second; 16-channel logic analyzer (MSO models only); arbitrary waveform generator; USB3.0 connection and power (no need for external power supply!); serial decoding and mask-testing; free Windows, Linux and Mac software.

Recent YouTube Videos
1. How to use Rigol's EMI Bundle Option to turn your Spectrum Analyzer into a powerful pre-compliance tool. Pass EMI tests every time!

2. Understanding PicoScope Automotive Waveforms  

3. Siglent SDS2000X Series Oscilloscopes - Feature Review 

4. Oscilloscope Probes - an introduction from Teledyne LeCroy

5. Siglent SDG2000X Signal Generators 


6. Jack Ganssle's Review of Rigol's DSA815-TG Spectrum Analyzer

Recent Tweets (follow us!!)

Saelig Twitter
Saelig Twitter
How To Make Great oscilloscope Measurements.

Innovation! Pizza ATM Serves Up Pies on College Campus!   

LabView drivers now available for almost all Siglent units. 

Online demos are fun! Here are hands-on Oscilloscope, Spectrum Analyzer and Amplitude Modulation demos.
Alstom ImageBombardierRail and Alstom have chosen ABI's BoardMaster to reduce repair costs & turnaround time.