Electronic Components

Transistors, as you probably know, are fundamental electronic devices used to amplify and switch current signals. When combined in a circuit, they can be used for the simultaneous control of a number of devices. That's the power of transistor arrays--semiconductor integrated circuits which combine a number of transistors within a solid substrate.

Transistor arrays are an important component of circuits used in all sorts of equipment and applications. Buying a drink at a vending machine, being cooled by an air conditioner, communicating via fax machine, or riding an elevator are just some of the devices we use every day which incorporate transistor arrays.

For those of us who use these individual components, Texas Instruments has released an upgrade of the popular ULN2003 series: the ULN2003LV. This 7-channel transistor array may be just what the doctor (or electrical engineer) ordered for low-voltage (3V-to-5V) relay and inductive coil applications.

What is special about the ULN2003LV is its low impedance drivers which minimize on-chip power dissipation - up to 5 times lower than typical 3V relays. Additionally, it has an input interface that reduces current drawn from the external drivers. Compatibility-wise, the ULN2003LV is quite versatile, featuring support for 3.3V to 5V CMOS logic input interfaces, and pin-to-pin compatibility with other ULN2003 devices in similar packages.

Specific uses for the ULN2003LV include:

• Relay and inductive load drivers in various telecom, consumer, and industrial applications
• Lamp and LED displays
• Logic level shifters
  

Of course, the function of the transistor array is as broad as its range of use. What are some of the projects you've used transistor arrays for?

This post was sponsored by Texas Instruments Standard Linear and Logic, a client of GlobalSpec.

Click to view the ULN2003LV datasheet.

Do you work in an industry where you may need dozens or even thousands of double-throw, double-pole multiplexers? Perhaps you need one that offers the flexibility of a single-pole, double-throw switch?

Texas Instruments has released a powerful, dual USB and mobile high-definition link multiplexer that proves everything really is bigger in Texas! Except the Cowboys, of course.

Word is upon your application of TI's TS3 USB 3200 you will have the unrivaled capability to control USB access at exceptionally high transfer speeds. I can't wait to get my own - and I'll tell you how to get one for free, momentarily.

I doubt that I need to tell you what Universal Serial Bus 2.0 is, but you'd probably like to know that this device is compatible with Mini-USB as well. One notable feature is the recently developed mobile high-definition link (MHL) that will more than likely become the new standard for connecting portable electronics (phones, tablets) to HD displays. This allows the USB switch to transfer HD information quickly and easily. This will certainly come in handy in places like call centers and tech departments, where workers may need to quickly switch between speakers, headsets, I/O devices, and network adapters with little fuss.

And I'll tell you what, TI loaded this USB switch with tons of features. So many features that it makes my ten gallon hat spin.

Another useful feature of this device is its a flexible power control, as it that can utilize the its pin's power rails to operate with or without and positive power supply. The 3200 has considerable overvoltage tolerance as well. For a full diagram of how the TS3 USB 3200's pin configuration lies, check out the manufacturer-supplied diagram below. Another useful feature of this device is its a flexible power control, as it can utilize the its pin's power rails to operate with or without positive power supply. The 3200 has considerable overvoltage tolerance as well. For a full diagram of how the TS3 USB 3200's pin configuration lies, check out the manufacturer-supplied diagram to the right.

Oh, and you know what's super cool about Texas Instuments? They'll give you a sample of this terrific device absolutely free. That's right, sign up for a TI industrial account, and you'll get one of these handy devices for nada.

I think that proves that not only is everything bigger in Texas, but also much more hospitable!

This post was sponsored by Texas Instruments Standard Linear and Logic, a client of GlobalSpec.

Click to view the TS3 USB 3200 datasheet.

High-side load switches are tiny devices that pack a big punch when it comes to load control through a system. You may not even realize that your cell phone, MP3, and GPS devices all use this electrical component. High-side load switches maximize battery life of Lithium ion and Alkaline battery powered systems by providing low quiescent current and low shutdown current.

High-side load switches are controlled by an external enable signal, and are used for connecting or disconnecting a power source, such as a battery or adaptor, from a given load. They are commonly used in applications such as battery-powered portable devices.

A high-side load switch is different than a low-side switch and a high-side power switch.

• Low side load switches connect or disconnect the load to the ground and therefore sinks current into the ground.
• A high-power switch manages the output power and limits its output current.

High-side load switches pass the input voltage and current into the load and do not incorporate a current-limiting function. The devices are composed of three elements:

1. A pass element
2. A gate-control block
3. An input logic block

Texas Instruments TPS27081A Load Switch

Texas Instruments has created a 1.2 - 8V, 3A PFET High Side Load Switch with Level Shift & Adjustable Slew Rate Control. This device integrates a power positive channel field effect transistor (PFET) and a control NMOS in a tiny package. Known as the TPS27081A, the load switch is fully protected against electrostatic discharge capability (ESD) strikes on all pins providing better ESD with all other on-board components. The internal components are rated for up to 8V supply and support up to 3A of load current. They can be used in a variety of applications.

Application diagram. Image Credit: TI

Specific applications for the high-side load switch include:

• LCD panels, which require inrush current control to prevent system damages, as well as standby power isolation applications
• Prevention of current leakage
• Provide a true shut down for boost regulators

Texas Instruments offers a high-quality product that has low ON resistance and high current PFET to suit your system's needs. The slew rate is a vector representing the maximum rate of change of a signal. In an electrical circuit it is defined as a maximum rate of change of the output voltage and is represented by volts per second (V/S).

What experience do you have with high-side load switches? Are you carrying one on you now?

This post was sponsored by Texas Instruments Standard Linear and Logic, a client of GlobalSpec.

Click to view the 1.2 - 8V, 3A PFET High Side Load Switch datasheet.

Who is designing products to withstand the effects of EMP events? What type of devices can protect against EMP events such as those caused by a nuclear explosion? What shielding methods would be appropriate?

The preceding article is a "sneak peek" from Electronic Components, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Electronic Components today.

Aside from nanotechnology, what other technologies do you think could be considered as "white hat" technologies? What responsibilities are there in promoting new technology developments?

The preceding article is a "sneak peek" from Electronic Components, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Electronic Components today.

What have your experiences been in terms of the quality of the electronic products you currently buy? What is to blame for the deteriorating quality in today's electronics industry and how can it be addressed?

The preceding article is a "sneak peek" from Electronic Components, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Electronic Components today.