LM317T Voltage Regulator with Pass Transistor

Designers of today's systems with battery supplies and common 3.3V and 5V rails are faced with the challenge of powering devices that require higher voltages to operate, such as displays, line drivers, rotating media, RF amplifiers and backlights. For example, some peripheral displays in portable applications use backlighting with 5 leds that need 15V to 20V to power the string, but a typical battery configuration may only provide 4V to 8V. Nationals latest boost and buck-boost regulators give designers the ability to achieve the output voltage necessary for these peripheral devices. In addition, with excellent performance-to-power ratios, the high-efficiency boost and buck-boost regulators fall into Nationals powerwise® family of energy efficient products.



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