LTC2951-1/LTC2951-2 Pushbutton On/Off Controller FEATURESDESCRIPTION n Adjustable Pushbutton Debounce and Delay Timers The LTC®2951 is a micropower, wide input voltage range n Low Supply Current: 6µA pushbutton ON/OFF controller. The part contains a push- n Wide Operating Voltage Range: 2.7V to 26.4V button input which controls the toggling of an open-drain n EN Output (LTC2951-1) Allows DC/DC Converter enable output. The pushbutton turn OFF debounce time Control is externally programmable, while the turn ON debounce n EN Output (LTC2951-2) Allows Circuit Breaker time is fixed at 128ms. A simple microprocessor interface Control allows for proper system housekeeping prior to power- n Simple Interface Allows Graceful µP Shutdown down. Under system fault conditions, an adjustable KILL n High Input Voltage PB Pin with Internal Pull-Up timeout delay ensures proper power-down. Resistor The LTC2951 operates over a 2.7V to 26.4V input voltage n ±10kV ESD HBM on PB Input range to accommodate a variety of input power supplies. n Accurate 0.6V Threshold on KILL Comparator Input Very low quiescent current (6µA typical) makes the n 8-Pin 3mm × 2mm DFN and ThinSOTTM Packages LTC2951 ideally suited for battery powered applications. APPLICATIONS Two versions of the part are available to accommodate either positive or negative enable polarities. The parts n Portable Instrumentation Meters are available in 8-pin 3mm × 2mm DFN and ThinSOT n Blade Servers packages. n Portable Customer Service PDA L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n Desktop and Notebook Computers ThinSOT and PowerPath are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION VIN 2.7V TO 26.4V Turn-On Debounce VIN VOUT DC/DC BUCK SHDN** EN R1 VIN EN 10k 2V/DIV LTC2951-1 INT INT µP/µC 128ms PB PB KILL KILL GND KILLT OFFT CKILLT* COFFT* 0.033µF 0.033µF *OPTIONAL 25ms/DIV 2951 TA01b 2951 TA01 **SHDN INTERNALLY PULLED UP BY DC/DC 295112fb 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Timing Diagrams Applications Information Typical Applications Package Description Revision History Typical Application Related Parts