The LM22671 switch regulator provides all the necessary features to achieve an effective high voltage step-down (step-down) regulator using a minimum of external components. This easy-to-use regulator contains a 42 V n-channel MOSFET switch capable of delivering load currents up to 500 mA. Good line and load regulation, high efficiency (> 90%) is featured. Voltage mode control provides a shorter minimum turn-on time, allowing the widest input and output voltage ratio.
Simplified Application Schematic
Internal loop compensation means that the user does not need to calculate the loop compensation component. Fixed 5v output and adjustable output voltage options are available. The default switching frequency is set to 500 KHZ and small is allowed. External components have good transient response.
Pin Configuration
In addition, the frequency can be adjusted with an external resistor in the range of 200 kHz to 1 MHz. Internal oscillators can be synchronized to one system clock or another regulator's oscillator. A precise enable input allows for simplified regulator control and system power sequencing. In off mode, the regulator absorbs only 25µA(typical). An adjustable soft start function is provided by selecting a single external capacitor. The LM22671 also has built-in thermal shut-off and current limiting to prevent accidental overload.
The LM22671 is a family member of the Texas Instruments SIMPLE SWITCHER. The SIMPLE SWITCHER concept provides an easy external component and TI WEBENCH design tool. TI's WEBENCH tool includes features such as external component calculations, electrical simulation, thermal simulation and easy-to-design Build-It boards.
Principle block diagram
