LM26420

The LM26420 regulator is a monolithic, high frequency, dual PWM step-down DC/DC converter in a 16 Pin LLP and a 20 Pin eTSSOP package. It provides all the active functions to provide local DC/DC conversion with fast transient response and accurate regulation in the smallest possible PCB area. With a minimum of external components, the LM26420 is easy to use. The ability to drive two 2.0A loads with an internal 75 mΩ PMOS top switch and an internal 50 mΩ NMOS bottom switch using state-of-the-art 0.5 µm BiCMOS technology results in the best power density available. The world-class control circuitry allows on-times as low as 30ns, thus supporting exceptionally high frequency conversion over the entire 3V to 5.5V input operating range down to the minimum output voltage of 0.8V. Switching frequency is internally set to 550 kHz or 2.2 MHz, allowing the use of extremely small surface mount inductors and chip capacitors. Even though the operating frequency is high, efficiencies up to 93% are easy to achieve. External shutdown is included, featuring an ultra-low stand-by current. The LM26420 utilizes current-mode control and internal compensation to provide high-performance regulation over a wide range of operating conditions. Additional features include internal soft-start circuitry to reduce inrush current, pulse-by-pulse current limit, thermal shutdown, power good indicators, precision enables, and output over-voltage protection.

Application Notes