●The LM3489 device is a high-efficiency PFET switching regulator controller that can be used to quickly and easily develop a small, cost-effective, switching buck regulator for a wide range of applications. The hysteretic control architecture provides for simple design without any control loop stability concerns using a wide variety of external components. The PFET architecture also allows for low component count as well as ultra-low dropout, 100% duty cycle operation. Another benefit is high efficiency operation at light loads without an increase in output ripple. A dedicated enable pin provides a shutdown mode drawing only 7 µA. Leaving the enable pin unconnected defaults to on.
●Current limit protection can be implemented by measuring the voltage across the PFETs RDS(ON), thus eliminating the need for a sense resistor. A sense resistor may be used to improve current limit accuracy if desired. The cycle-by-cycle current limit can be adjusted with a single resistor, ensuring safe operation over a range of output currents.
● Qualified for Automotive Parts
● AEC-Q100 Qualified With the Following Results:
● Device Temperature Grade 1: –40°C to 125°C Ambient Operating Temperature Range
● Device HBM ESD Classification Level 2
● Device CDM ESD Classification Level C5
● Easy-to-Use Control Methodology
● No Control Loop Compensation Required
● Wide 4.5-V to 35-V Input Range
● 1.239 V to VIN Adjustable Output Range
● High Efficiency: 93%
● ±1.3% (±2% Over Temperature) Internal Reference
● 100% Duty Cycle Operation
● Maximum Operation Frequency > 1 MHz
● Current Limit Protection
● Dedicated Enable Pin (on if Unconnected)
● Shutdown Mode Draws Only 7-µA Supply Current
● 8-Pin VSSOP Package
Part 3D Model
