LT3085 Adjustable 500mA Single Resistor Low Dropout Regulator FEATURESDESCRIPTION n Outputs May be Paralleled for Higher Current and The LT®3085 is a 500mA low dropout linear regulator that Heat Spreading can be paralleled to increase output current or spread n Output Current: 500mA heat on surface mounted boards. Designed as a precision n Single Resistor Programs Output Voltage current source and voltage follower, this new regulator n 1% Initial Accuracy of SET Pin Current fi nds use in many applications requiring high current, n Output Adjustable to 0V adjustability to zero, and no heat sink. The device also n Current Limit Constant with Temperature brings out the collector of the pass transistor to allow n Low Output Noise: 40μVRMS (10Hz to 100kHz) low dropout operation—down to 275mV—when used n Wide Input Voltage Range: 1.2V to 36V with a second supply. n Low Dropout Voltage: 275mV A key feature of the LT3085 is the capability to supply a n < 1mV Load Regulation wide output voltage range. By using a reference current n < 0.001%/ V Line Regulation through a single resistor, the output voltage is programmed n Minimum Load Current: 0.5mA to any level between zero and 36V. The LT3085 is stable n Stable with Minimum 2.2μF Ceramic Capacitor with 2.2μF of capacitance on the output, and the IC uses n Current Limit with Foldback and Overtemperature small ceramic capacitors that do not require additional Protected ESR as is common with other regulators. n 8-Lead MSOP, and 6-Lead 2mm × 3mm DFN Packages Internal protection circuitry includes current limiting APPLICATIONS and thermal limiting. The LT3085 is offered in the 8-lead MSOP and a low profi le (0.75mm) 6-lead 2mm × 3mm n High Current All Surface Mount Supply DFN package (both with an Exposed Pad for better thermal n High Effi ciency Linear Regulator characteristics). n Post Regulator for Switching Supplies n Low Parts Count Variable Voltage Supply L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and VLDO and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the n Low Output Voltage Power Supplies property of their respective owners. TYPICAL APPLICATIONVariable Output Voltage 500mA Supply N = 1676 V IN LT3085 IN 1.2V TO 36V VCONTROL + 1μF – OUT VOUT SET 2.2μF RSET VOUT = RSET • 10μA 9.80 9.90 10.00 10.10 10.20 3085 TA01a SET PIN CURRENT DISTRIBUTION (μA) 3085 TA01b 3085fb 1 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS BLOCK DIAGRAM APPLICATIONS INFORMATION TYPICAL APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS