LM25085A数据手册集成电路（IC）的PMIC-稳压器-DCDC开关式控制器规格书PDF

描述 Description

The LM25085A is a functional variant of the LM25085 COT PFET Buck Switching Controller. The functional differences of the LM25085A are: The feedback reference voltage is 0.9V, the forced off-time after current limit detection is longer, and the soft-start time is shorter (1.8 ms).The LM25085A 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

• 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 0.9V
• Precision ±2% Feedback Reference
• Capable of 100% Duty Cycle Operation
• Internal Soft-Start Timer
• Integrated High Voltage Bias Regulator
• Thermal Shutdown