National Semi Introduces SIMPLE SWITCHER Synchronous Regulators
National Semiconductor Corp. announced the addition of two new, high-efficiency SIMPLE SWITCHER® synchronous buck regulators to its PowerWise® energy-efficient product family.
The highly integrated LM3102 and LM3103 are claimed to be the industry’s first synchronous buck regulators to feature an input voltage range up to 42V. Optimized for powering digital integrated circuits (ICs) in industrial and telecommunication applications, the 2.5A LM3102 and the 750mA LM3103 extends National’s SIMPLE SWITCHER synchronous product line which includes the 1.5A LM3100.
Along with the LM3100, National’s new LM3102 and LM3103 are said to deliver up to 97% efficiency, which is eight points higher than comparable non-synchronous products. Integration of MOSFET switches and the use of small inductors enables a reduced system component count and very small solution size.
The buck regulators utilize a constant on-time (COT) control scheme, which requires no loop compensation. They also include a patented integrated flywheel current injection control (FCIC), which allows for the use of ceramic capacitors rather than bulkier tantalum capacitors. The new LM3102 and LM3103, along with all of National’s SIMPLE SWITCHER products, are said to be quick and easy to design using National’s online WEBENCH® power supply design tools. The LM3102 and LM3103 synchronous, step-down switching voltage regulators accept an input voltage between 4.5 and 42V and have a programmable switching frequency up to 1 MHz.
The LM3102 supplies up to 2.5A of current to loads with an output voltage as low as 0.8V. The LM3103 supplies up to 750mA of current to output voltages as low as 0.6V. Both regulators are claimed to feature excellent line and load regulation. The LM3102 and LM3103 also run in discontinuous mode for improved efficiency during light load conditions. The regulators will not discharge a pre-biased output capacitor during start-up, ensuring a monotonic voltage ramp. The products offer additional features such as programmable soft-start, valley current limit, output over-voltage protection and thermal shutdown for extra protection.
The LM3102 and LM3103 are available now. The LM3102 is priced at $2.65 each and is offered in a 20-pin TSSOP with exposed pad. The LM3103 is priced at $2.00 each and is offered in a 16-pin TSSOP package with exposed pad for improved thermal performance. All prices are in 1,000-unit quantities.
