描述 Description

The LM20146 is a full featured adjustable frequency synchronous buck regulator capable of delivering up to 6A of continuous output current. The current mode control loop can be compensated to be stable with virtually any type of output capacitor. For most cases, compensating the device only requires two external components, providing maximum flexibility and ease of use. The device is optimized to work over the input voltage range of 2.95V to 5.5V making it suitable for a wide variety of low voltage systems.
The device features internal over voltage protection (OVP) and over current protection (OCP) circuits for increased system reliability. A precision enable pin and integrated UVLO allows the turn-on of the device to be tightly controlled and sequenced. Start-up inrush currents are limited by both an internally fixed and externally adjustable Soft-Start circuit. Fault detection and supply sequencing are possible with the integrated power good circuit.
The LM20146 is designed to work well in multi-rail power supply architectures. The output voltage of the device can be configured to track a higher voltage rail using the SS/TRK pin. If the output of the LM20146 is pre-biased at startup it will not pull the ouput low.
The frequency of this device can be adjusted from 250 kHz to 750 kHz by connecting an external resistor from the RT pin to ground.
The LM20146 is offered in a 16-pin HTSSOP package with an exposed pad that can be soldered to the PCB, eliminating the need for bulky heatsinks.

特性 Features

? Input Voltage Range 2.95V to 5.5V
? Accurate Current Limit Minimizes Inductor Size
? 97% Peak Efficiency
? Adjustable Switching Frequency (250 kHz to 750 kHz)
? 16m? and 20m? Integrated FET Switches
? Starts up into Pre-biased Loads
? Output Voltage Tracking
? Peak Current Mode Control
? Adjustable Output Voltage Down to 0.8V
? Adjustable Soft-Start with External Capacitor
? Precision Enable Pin with Hysteresis
? Integrated OVP, UVLO, Power Good and Thermal Shutdown
? 16-Pin HTSSOP Exposed Pad Package