LM5085 75V Constant On-Time PFET Buck Switching Controller from the PowerWise® Family

Features:

LM5085Q is an Automotive Grade product that is AEC-Q100 grade 1 qualified (-40¡ãC to 125¡ãC operating junction temperature)
Wide 4.5V to 75V 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 ¡À2% feedback reference
Capable of 100% duty cycle operation
Internal soft-start timer
Integrated high voltage bias regulator
Thermal shutdown

Description:

The LM5085 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 75V 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.