描述 Description

The LM25085 is a high efficiency PFET switching regulator controller that can be used to quickly and easily develop a small, efficient buck regulator for a wide range of applications. This high voltage controller contains a PFET gate driver and a high voltage bias regulator which operates over a wide 4.5V to 42V input range. The constant on-time regulation principle requires no loop compensation, simplifies circuit implementation, and results in ultra-fast load transient response. The operating frequency remains nearly constant with line and load variations due to the inverse relationship between the input voltage and the on-time. The PFET architecture allows 100% duty cycle operation for a low dropout voltage. Either the RDS(ON) of the PFET or an external sense resistor can be used to sense current for over-current detection.

特性 Features

? LM25085-Q1 is an Automotive Grade product that is AEC-Q100 Grade 1 Qualified (–40°C to 125°C Operating Junction Temperature)
? Wide 4.5V to 42V Input Voltage Range
? Adjustable Current Limit Using RDS(ON) or a Current Sense Resistor
? Programmable Switching Frequency to 1MHz
? No Loop Compensation Required
? Ultra-Fast Transient Response
? Nearly Constant Operating Frequency with Line and Load Variations
? Adjustable Output Voltage from 1.25V
? Precision ±2% Feedback Reference
? Capable of 100% Duty Cycle Operation
? Internal Soft-Start Timer
? Integrated High Voltage Bias Regulator
? Thermal Shutdown