NATIONAL SEMICONDUCTOR INTRODUCES INDUSTRY’S SMALLEST HIGH-EFFICIENCY POWER CONTROLLER FOR NOTEBOOK PCS AND OTHER BATTERY-OPERATED SYSTEMS

March 12, 1998 – Addressing the size and power needs of the portable PC market, National Semiconductor Corporation® today announced the industry’s smallest high-efficiency synchronous step-down power controller. Housed in a space-saving, ultra-thin package that occupies just 6 X 6 mm2 of board space, the LM2630 is ideal for a variety of space-constrained battery-powered systems. Moreover, the new device provides all the functions needed for step-down switching conversion in notebook PCs, handheld instruments, PDAs and mobile communications.

“The LM2630 marries advanced control techniques with National’s proven expertise in the DC/DC converter technology,” said Venkatesh Shan, National’s director of marketing for power management products. “In addition, it provides the ‘core’ block needed to forward-integrate a complete power supply solution and prolong battery life in portable PCs.”

National's LM2630 takes advantage of the highest performance N-channel MOSFET technology available today to achieve high output current. Efficiencies of 92% and greater are common in typical 3A applications. Under light load conditions, the device uses a pulse-skipping mode approach to increase efficiencies.

The LM2630’s high performance can also be attributed to a current mode control scheme that quickly achieves output voltage with fast loop response and superior line regulation of 0.002%/V. Other performance features include load regulation of 0.3% and a power-good function that indicates the state of the output voltage.

A power-saving sleep mode extends battery life by reducing quiescent current from a typical 0.8 milliamp to less than 0.1 microamp. Protection circuitry includes adjustable soft-start, thermal shutdown, undervoltage and overvoltage latch-off, cycle-by-cycle current limit and latch-off current limits.

Input supply voltages can vary from 4.5V to 30V, making the device compatible with any of the currently used battery chemistries. Output range is adjustable from 1.8V to 6V. Operating frequency is also adjustable between 200kHz and 400kHz.

Price and Availability
The LM2630MTC is currently available in National's 20-pin TSSOP, and is priced at $3.00 each when purchased in quantities of 1000.

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, California, and focuses on the communications, personal systems and consumer markets. National has annual sales of approximately $2.5 billion and 13,000 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.