描述 Description

The TPS6420x are nonsynchronous step-down controllers that are ideally suited for systems powered from a 5-V or 3.3-V bus or for applications powered from a 1-cell Li-Ion battery or from a 2- to 4-cell NiCd, NiMH, or alkaline battery. These step-down controllers drive an external P-channel MOSFET allowing design flexibility. To achieve highest efficiency over a wide load current range, this controller uses a minimum on time, minimum off time control scheme and consumes only 20-μA quiescent current. The minimum on time of typically 600 ns (TPS64203) allows the use of small inductors and capacitors. When disabled, the current consumption is reduced to less than 1 μA. The TPS6420x is available in the 6-pin SOT23 (DBV) package and operates over a free air temperature range of ?40°C to 85°C.

特性 Features

? Step-Down Controller for Applications With up to 95% Efficiency
? 1.8-V to 6.5-V Operating Input Voltage Range
? Adjustable Output Voltage Range From 1.2 V to VI
? High Efficiency Over a Wide Load Current Range
? 100% Maximum Duty Cycle for Lowest Dropout
? Internal Softstart
? 20-μA Quiescent Current (Typical)
? Overcurrent Protected
? Available in a SOT23 Package
? APPLICATIONS
? USB Powered Peripherals
? Organizers, PDAs, and Handheld PCs
? Low Power DSP Supply
? Digital Cameras
? Hard Disk Drives
? Portable Audio Players