LM3485MMX/NOPB Texas Instruments 开关控制器 Hysteretic PFET Buck Cntlr

1 Features 3 Description

1 The LM3485 is a high-efficiency PFET switching • Easy-to-Use Control Methodology

regulator controller that can be used to quickly and

• No Control-Loop Compensation Required easily develop a small, low-cost, switching buck

• 4.5-V to 35-V Wide Input Range regulator for a wide range of applications. The

• 1.242-V to V hysteretic control architecture provides for simple IN Adjustable Output Range

design without any control-loop stability concerns

• High Efficiency 93% using a wide variety of external components. The

• ±1.3% (±2% Over Temp) Internal Reference PFET architecture also allows for low component

• 100% Duty Cycle count as well as ultralow dropout, 100% duty cycle

operation. Another benefit is high efficiency operation • Maximum Operating Frequency > 1 MHz

at light loads without an increase in output ripple.

• Current Limit Protection

Current limit protection is provided by measuring the

2 Applications voltage across the RDS(ON) of the PFET, thus

eliminating the need for a sense resistor. The cycle•

Set-Top Box by-cycle current limit can be adjusted with a single

• DSL or Cable Modem resistor, ensuring safe operation over a range of

output currents. • PC/IA

• Auto PC Device Information(1)

• TFT Monitor PART NUMBER PACKAGE BODY SIZE (NOM)

• Battery-Powered Portable Applications LM3485 VSSOP (8) 3.0 mm × 3.0 mm

• Distributed Power Systems (1) For all available packages, see the orderable addendum at

• Always On Power