National Semiconductor Reduces Noise Problems to New Benchmark Lows With Space-Qualified FACT Quiet Series® Logic Family

October 31, 1997 - National Semiconductor Corporation® today announced availability of the QML-V Qualified FACT Quiet Series logic family- the first advanced CMOS logic devices to meet the noise problems of ground bounce, dynamic threshold and high EMI in space-qualified applications. The new space-qualified FACT Quiet Series logic family is specifically designed to implement octal and 16-bit bus driving functions for communications and solid state recorder sub-systems in low earth-orbiting satellites.

"Controlling circuit noise is important for high performance because as advanced CMOS devices run at higher clock rates or switch faster, they generate more system noise," noted Jon Ewald, National's mil/aero product marketing manager. This expected, but unwanted by-product of high-speed CMOS technology harms clear signaling and degrades performance.

"Until now there was no advanced CMOS space-qualified device that addresses noise issues," he added. "Before, if significant noise issues arose, designers were forced to re-design the system, use a non-space-qualified FACT Quiet Series part, or employ another lower-performing CMOS part."

QML-V Qualified FACT Quiet Series logic features high speed, low device-generated noise (ground bounce), high drive, low power consumption and up to 100krads RHD (Rad Hard Assurance). Propagation delay is 8.5nsec; ground bounce is 1.5V maximum; high drive is +24/-24mA; and (Icc) power consumption at 5.5V is 80 microamps. The devices operate from 5V supplies.

The series uses special circuitry to reduce voltage undershoot and overshoot, and to shape the waveform. This circuitry includes: Output waveshaping-graduated turn-on (GTO) and undershoot correction (USC) to reduce high frequency signal components and minimize undershoot. The series has TTL-compatible inputs, features a split power bus to physically isolate the input and output ground, and reduces total leadframe inductance.

National's QML-V Qualified FACT Quiet Series logic family has become the standard for CMOS logic in 100 krad RHA space applications. The new 54ACTQ family further underscores National Semiconductor's continuing commitment to provide systems-oriented solutions for mil/aero customers.

The 54ACTQ family fully meets Mil-Prf 38535 QML-V under National's DESC (Defense Electronics Supply Center)-validated QML system.

Availability
FACT Quiet Series 54ACTQ devices are housed in ceramic DIP, flatpack and LCC packages and are available from National or its authorized distributors.

For more information on 54ACTQ space-qualified devices or other National QML system-oriented products, please visit our web site at http://www.national.com/appinfo/milaero.

National Semiconductor Corporation, a Fortune 500 company, produces system-on-a-chip silicon solutions for the information highway, based on its leadership in analog and mixed signal technologies. National is headquartered in Santa Clara, Calif., and focuses on the communications, personal systems and consumer markets. National has annual sales of approximately $2.5 billion and 12,700 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.

Editor’s Note: FACT Quiet Series® is a registered trademark of Fairchild Semiconductor.