20 Years On - National Semiconductor's SIMPLE SWITCHER Products and Software Continue to Make Power Design Simple

National introduced its first generation of SIMPLE SWITCHER regulators in 1990. Unique and unheard of at the time, the products were created to enable any designer, even a novice, to easily and quickly design a highly efficient switching power solution.

The LM257x family of four products featured a wide input voltage range from 4V to 60V, supported currents up to 3A, operated at 52 kHz, and was offered in through-hole and surface mount packages. A typical design delivered peak efficiencies up to 89 percent and required just five components…simple.

A software tool, the first of its kind running on the DOS personal computers of the time, made the complex calculations to create a design…even simpler.

“In the early 1990’s, design engineers were unsure about how to create a discrete switching power supply design,” said Alex Chin, Business Unit Director for National’s SIMPLE SWITCHER products. “The design team at National created a family of SIMPLE SWITCHER products along with the ‘Switcher Made Simple’ software, and offered guaranteed operational reference designs, which helped system designers get their products to market more quickly.

Today, the award-winning portfolio has evolved from the original four products to over 385 products, all of which are now included in the easy-to-use WEBENCH Power Designer software.

Compared to the first generation, the latest SIMPLE SWITCHER products, the LMZ1420x, LMZ1200x and LMZ1050x power modules, deliver megahertz switching frequency, 96 percent efficiency, full current operation above 100 degrees C, and EMI performance well below CISPR 22 restrictive emission levels. Now, a single integrated TO-PMOD package (similar to the industry-standard TO-263) includes all the inductors, diodes, regulators, resistors and capacitors…simpler today.

“While we are now in the midst of roughly the fifth generation of SIMPLE SWITCHER products, the demand for easy-to-use products continues to grow,” said Chin. “Design engineers are much savvier today, but the complexity of power designs has continued to evolve, with more point-of-load requirements due to the increase in electronic content in end-applications. We will continue to tackle complex designs to help the engineer and develop new products to expand the product family…to make power design easier than ever.”