LM25085ASDX

• Wide input voltage range of 4.5V to 42V
• Adjustable current limit used R_DS（ON）or current sense resistors
• Programmable switching frequency up to 1MHz
• No loop compensation is required
• Ultra-fast transient response
• Nearly constant line and load varying operating frequency
• Adjustable output voltage from 0.9V
• Accuracy± 2% feedback reference
• Can work at 100% duty cycle
• Internal soft-start timer
• Integrated high voltage bias regulator
• Thermal shutdown

illustrate

The LM25085A is a functional variant of COT PFET's LM25085 buck switch controller. The functional differences of the LM25085A are a feedback reference voltage of 0.9V, longer forced shutdown times after current limit detection, and shorter soft-start times (1.8 ms).

The LM25085A is a high efficiency PFET, switching regulator controller that can be used to quickly and easily develop a small, high efficiency buck regulator for a wide range of applications. This high voltage controller contains a gate driver for PFET and a wide 4.5V to 42V input range with high voltage bias regulation. The principle of constant on-time regulation, eliminating the need for loop compensation, simplifies the implementation of circuits, and results in ultra-fast load transient response. The operating frequency remains almost constant due to the inverse relationship between the input voltage and the time due to the inverse relationship between the line and the load. The architecture of the PFET allows 100% duty cycle operation of low dropout. Either PFET, or an external sense resistor R_{DS（ON），}It can be used to detect current overcurrent detection.