LM3489MMX

• Easy-to-use control method
• No control loop compensation required
• Wide 4.5V input range to 35V
• 1.239V to V_INAdjustable output range
• High efficiency: 93%
• ± 1.3% (± 2% temperature) internal reference
• 100% duty cycle operation
• The maximum operating frequency > 1MHz
• Current limit protection
• Dedicated start pin (if not connected)
• Shutdown mode draws only 7μA
• MSOP - 8
• LM3489 is AEC - Q100 Class 1 qualified

illustrate

The LM3489 is a high efficiency PFET switching regulator controller that can be used to quickly and easily develop small, cost-effective, exchangeable buck regulators for a wide range of applications. The hysteresis control architecture is a simple design that controls the stability of the loop without any use of external components, a wide variety of concerns. The PFET architecture also allows low component count and ultra-low dropout 100% duty cycle operation. Another benefit is high efficiency at light loads without increasing the output ripple of the operation. A dedicated enable pin provides a shutdown mode graph of only 7μA. Leaving the enable pin dangling defaults to Up.

Current limiting protection can be achieved by measuring the R of the PFET_DS（ON）voltage, thus eliminating the need for a sense resistor. Sense resistors can be used to improve existing limits if accuracy is required. During the cycle-by-cycle current limit, an adjustable resistor ensures safe operation over the output current range.

apply

• Stb
• DSL/cable modem
• PC / IA
• Automatic computer
• LCD
• Battery-powered portable applications
• Distributed power systems
• Always on power
• High power LED driver
• Car