National Semiconductor Corp. (Santa Clara, CA) introduced the LM2653 high-efficiency switching regulator. The LM2653 offers 1.5A output in a self-contained TSSOP-16 package measuring 5mm x 4.4mm x 1.1mm. The device is considered ideal as a power management solution for space-constrained portable devices that require high efficiency and high output current in a small package.According to National Semiconductor, the LM2653's 1.5A output is the highest available in a TSSOP package. The device is claimed to provide efficient power conversion over a 100:1 load ratio, and includes a number of power-saving features to maximize efficiency. During light loads, for example, the regulator enters a low-power hysteretic mode. The device uses synchronous rectification to achieve 97 percent efficiency.The LM2653 generates an adjustable output as low as 1.5V from an input voltage range of 4V to 12V, enabling it to provide a variety of system voltages, including those of CPU I/O, video and memory chips. The device also features thermal shutdown, input undervoltage lockout, adjustable soft-start, cycle by cycle current limit, and output overvoltage and undervoltage protection. The LM2653 is priced at $3.15 in quantities of 1,000.