• Efficiency Up to 94%

• Simple and Easy to Design With (Using Off-the- Shelf External Components)

• 150-mΩ DMOS Output Switch

• 3.3-V, 5-V, 12-V Fixed Output and Adjustable (1.2 V to 37 V) Versions

• 50-μA Standby Current When Switched OFF

• ±2% Maximum Output Tolerance Over Full Line and Load Conditions

• Wide Input Voltage Range: 8 V to 40 V

• 260-KHz Fixed Frequency Internal Oscillator

• –40 to 125°C Operating Junction Temperature Range

The LM2676 series of regulators are monolithic integrated circuits which provide all of the active functions for a step-down (buck) switching regulator capable of driving up to 3-A loads with excellent line and load regulation characteristics. High efficiency (>90%) is obtained through the use of a low ON-resistance DMOS power switch. The series consists of fixed output voltages of 3.3-V, 5-V, and 12-V and an adjustable output version.

The SIMPLE SWITCHER? concept provides for a complete design using a minimum number of external components. A high fixed frequency oscillator (260kHz) allows the use of physically smaller sized components. A family of standard inductors for use with the LM2676 are available from several manufacturers to greatly simplify the design process.

The LM2676 series also has built-in thermal shutdown, current limiting and an ON/OFF control input that can power down the regulator to a low 50-μA quiescent current standby condition. The output voltage is ensured to a ±2% tolerance. The clock frequency is controlled to within a ±11% tolerance.