ESD News Archives

Latex Gloves – Are You Allergic?


Many industrial manufacturing environments require workers to wear protective gloves, including during electronics and medical device production and assembly. Latex gloves not only protect workers from harmful chemicals but also protect products from worker contact and contamination during manufacturing Read more

ST 925 SMT Rework System–Three favorites combined into one nice savings


Save a few steps--and some money--with the Pace 925 SMT Rework System Pace has introduced a new low-cost “combination” system ideal for surface mount technology (SMT) rework. It’s worth adding up the savings by comparing the a la carte prices Read more

Metcal’s CV-5200 Connection Validation Soldering Station Changes Everything


You may or may not have heard about Metcal’s new soldering station, the CV-5200. The evolutionary tool removes much of the reliance on visual inspection of hand-soldered joints and adds a second, more technology-driven method for validating a successful Read more

Putting Your Components to the ESD Test

Posted on by Andy in ESD News, ESD Testing, Static Control Tips and Tricks Leave a comment

Testing ESD Sensitivity 

Testing the sensitivity of components to ESD can be done in a couple of different ways. Either way, you’re determining what it takes to make a device fail when subjected to an electrostatic discharge (ESD). The two primary models for ESD testing include Human Body Model (HBM) and Charged Device Model (CDM) testing.

The models can simulate events; though they can’t completely mimic the entire range of potential ESD events. These two tests, HBM and CDM however have proven to be successful at reproducing more than 99% of ESD field failure signatures. Through these tests industries can –

  • Create and quantify suitable on-chip protection
  • Make comparisons between devices
  • Form a classification system for ESD sensitivity to help ESD design and monitoring requirements of manufacturing and assembly settings
  • Access documented test procedures to substantiate reliable and repeatable results

Human Body Model (HBM) Testing

Kid with hair standing up ESD

Human Body Model (HBM) testing

It doesn’t take much to cause a discharge. Walk across the floor in your socks and you’ you add an electrostatic charge to your body. After doing so, if you were to touch your finger to a lead on a ESDS device or assembly, the body could discharge and possibly cause damage to the device.

The oldest and most common form of testing to classify ESD sensitivity–using an ESD simulator with a special output circuit called the Human Body Model (HBM). The device is placed in a test system and contact is made through a relay matrix and the device is zapped with ESDs.

The device is considered to have failed if it doesn’t meet the datasheet parameters using parametric and functional testing. Failures usually include junction damage, metal penetration, melting of metal layers, contact spiking and damaged gate oxides.

Charged Device Model (CDM) Testing

charged device model testing

Charged Device Model (CDM) testing

A charge can also come from an ESDS device and cause an ESD event. For instance, if a device slides down a feeder in an automated assembler, the device can become charged. If it were to touch the insertion head or another conductive device, a quick discharge may take place. This represents a Charged Device Model (CDM) event and is potentially more destructive than an HBM event. Damage can take place in as little as a nanosecond.

This type of event generally happens in automated-manufacturing environments where machines may always stay turned on and cause electronic integrated circuits (ICs) to become charged. If the part touches a grounded conductor, the built-up storage of energy discharges. CDM discharge depends mostly on the parasitic parameters of the discharge as well as the size and type of component package.

To test, the device is placed on a field plate with the leads pointing up; then the device is charged and discharged.

 

All-Spec EOS/ESD Audit Kit

All-Spec EOS/ESD Audit Kit

All-Spec carries a large selection of quality ESD testing and measurement equipment such as EOS/ESD audit kits, electrostatic field meters and static locators; surface resistivity meters; and ESD event, EMI field and RF signal detectors.

All-Spec also carries a comprehensive range of ESD-safe, static control grounding supplies and partners with industry leaders like  SCS, Desco, Simco-Ion and more to offer the best static control products on the market.

 


ESD–Smaller Parts, Bigger Problems

Posted on by Andy in ESD News, Static Control Tips and Tricks, Technical Articles Leave a comment

ESD Sparks Conversation

It’s no shock that smaller electronic parts have been causing bigger ESD (electrostatic dissipation) problems–serious problems that cause component damage and money. How much damage depends on the sensitivity or susceptibility of the device.

Thankfully you can put controls in place to significantly reduce ESD incidents. Preplanning, understanding causes and solutions, and wearing special fabrics and components will help.

Preplanning

  1. Design products and assemblies to be as protected as practical from ESD damage
  2. Decide how much of the environment needs to be controlled
  3. Identify the areas needing protection and ESD sensitive parts
  4. Define the electrostatic protected areas (EPAs)
  5. Define the areas where ESD sensitive parts (ESDs) will be handled
  6. Eliminate static generating processes to reduce electrostatic charge generation; keep processes and materials at the same electrostatic potential; provide appropriate ground paths to minimize charge generation and accumulation
  7. Use grounding, ionization, and conductive and dissipative static control materials to dissipate and neutralize
  8. Use grounding, ionization, and conductive and dissipative static control materials to dissipate and neutralize
  9. Protect products from ESD with proper grounding or shunting, static control packaging and material handling products

Areas needing ESD protection

Causes and effective solutions

ESD is a tiny version of lightning. As the current dissipates through an object, it’s seeking a low impedance path to ground to equalize potentials. In most cases, ESD currents will travel to ground via the metal chassis frame of a device. However, it’s well known that current will travel on every available path.

Table showing esd causes and solutions

Control the area

The first step is to ground all components of the workstation and the personnel (work surfaces, equipment, etc.) to the same electrical ground point, called the “common point ground” i.e., system or method for connecting two or more grounding conductors to the same electrical potential.

All-Spec carries all of the products listed below to help you control your environment and keep it safe from ESD.

ESD control materials

 


ESD Socks: To Wear, or Not to Wear?

Posted on by Michelle R. in ESD News Leave a comment

Simply put, yes. ESD shoes are made with a conductive material, but they require perspiration in the sock to provide a path-to-ground. With so many variables between people— especially in the winter, when people perspire less— additional footwear is necessary to provide consistent conditions that are more conducive to ESD protection.

blogSocks

What makes ESD socks special? A special conductive yarn that provides an electrical path— and relies less on the wearer’s skin resistance to give ESD protection regardless of the environment— is the main reason these specialized socks should be incorporated into any static-sensitive environment.

For a complete line of ESD garments, slip on All-Spec. Call us or visit us online  today!


From the Ground Up: 3 Steps to Stopping Static for Good

Posted on by Kathy S. in ESD News Leave a comment

From the Ground Up--3 Steps to Stopping Static for GoodGuarding your sensitive equipment from the ravages of static electricity can be daunting, especially if you have to outfit an entire team of engineers with static-safe materials. Knowing the requirements of your particular environment is the first step.

The second step? Know your dissipative mat. Whether you need it for the floor, table or workstation, make sure you understand its specifications—like RTG versus RTT. Do you know the difference?

Resistance to Ground (RTG) is the resistance from the mat to the ground point. It is the primary measurement for general auditing purposes. This measurement ensures your mat conducts a charge from a point on the surface to the ground point. The guideline in ESD STM-7.1 for RTG is 1×106 to 1×109 ohms. ANSI/ESD S-20.20 has an upper limit of <1×109 ohms.

Resistance to Top (RTT), also called Resistance to Point, is the resistance from one point on the mat’s surface to another, which is measured to help ensure consistent resistance. The ESD STM-7.1 guideline for RTT is >1×106 ohms.

When it comes to equipping your entire facility, staying on budget is also critical. Your third step is to shop All-Spec. All-Spec’s selection of ESD-safe benchtop and floor mats runs the gamut. And, at All-Spec prices, you can easily equip your team—and maybe a few others—with all the tools it needs to run smoothly.


Is Your ESD-Safe Range Safe Enough?

Posted on by Kathy S. in ESD News Leave a comment

Is Your ESD-Safe Range Safe EnoughAre you playing it safe? What about safe enough? When it comes to your sensitive electronic components and printed circuit boards (PCBs), are you doing enough to mitigate potentially expensive problems?

Before you buy the most expensive ESD-safe materials, make sure you understand your facility’s protocols. Operating within your specific safe range doesn’t mean you need to spend money unnecessarily. And, understanding the difference between static dissipative and static conductive will help.

A common “safe range” for a production floor is between 25 x 104 ohms to 35 x 106 ohms (or 25,000 to 35,000,000 ohms); however, this may vary depending on your production environment. Materials ranging from zero ohms to 106 ohms (or one million) are static conductive, and materials ranging from 106 ohms to 109 ohms (or one billion) are static dissipative. Electrons flow easily across the surface or through the bulk of conductive materials. For dissipative materials, charges flow to ground more slowly than with conductive materials.

Need help finding or evaluating the proper range for your environment? Protecting sensitive electronics doesn’t have to be risky business. Play it safe, and turn to All-Spec for operational efficiency across the board and across the production floor—for less.