TechBlog

In industrial applications, a digital-to-analog (D-to-A) interface may be rather straightforward but the analog-to-digital (A-to-D) converter (ADC) can be a challenge. The capacitive input stage of both delta-sigma and successive approximation register (SAR) interfaces used for the ADC requires signal capture within a limited time frame. An improper signal chain can cause ringing and oscillation and result in inaccurate readings. However, this is just one of many factors to consider when selecting an ADC.

Signal Chain

High-performance ADCs convert the output of an analog sensor to a digital format for a microcontroller or digital signal processor. The selection of the ADC must be part of a systems approach. “When somebody starts a design, you start with the sensor, you see what kind of output impedance it has and you choose an amplifier and resistors around the amplifier and you choose that configuration based on your sensor,” says Chuck Sins, applications engineer, National Semiconductor. “Based on the accuracy of your sensor and what you are ultimately trying to achieve, then I choose the resolution of the ADC.”

Continue reading ‘Signal Conditioning Issues’ »

RF Micro Devices, Inc. (RFMD) recently announced that effective immediately RFMD is reducing its investments in wireless systems, including cellular transceivers and GPS solutions, in order to focus on core semiconductor component opportunities, including cellular front ends and other components in RFMD’s Cellular Products Group (CPG) and the expanding portfolio of semiconductor components in RFMD’s Multi-Market Products Group (MPG).

As a result, RFMD currently expects to eliminate product development expenses related to its wireless systems business by approximately $75 million this fiscal year beginning in the June 2008 quarter, with the full benefit expected to be realized in the December 2008 quarter.

Bob Bruggeworth, president and CEO of RFMD, said, “These strategic actions will enable RFMD to deliver more predictable financial results and substantially higher profitability. We are the industry leader in RF components and the world’s largest manufacturer of compound semiconductors. We are investing in growing markets where we have a demonstrated track record of success, and we will measure our progress using operating income and return on invested capital (ROIC) as key performance metrics. We anticipate steady financial improvement throughout the year, and we currently forecast at least 10% non-GAAP operating income and double-digit ROIC by the end of the calendar year.

Continue reading ‘RFMD To Eliminate Approximately $75 Million In Wireless Systems Expenses’ »

An Australian inventor has come up with a gun that can fire 180 rounds in one hundredth of a second, or an impossible 1 million rounds a minute – so fast that a bullet enters the barrel before the preceding one has even left the muzzle.

Incredibly, storekeeper James Michael O’Dwyer’s gun has no moving parts and operates entirely on electrical impulses.

Despite the fact that O’Dwyer’s invention has vast and even dizzying implications as an awesome military weapon, when he approached Australian defense officials in 1994 with his idea they turned a deaf ear. And when he showed his gun to former U.S. Special Forces chief Gen. Wayne Downing, the general said O’Dwyer was “certifiably” crazy.

Continue reading ‘New Super Gun Fires Bullets Super Fast’ »