LT3085 Adjustable 500mA Single Resistor Low Dropout Regulator FEATURES DESCRIPTION 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 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: 40V (10Hz to 100kHz) RMS low dropout operationdown to 275mVwhen 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 2.2F Ceramic Capacitor with 2.2F 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 pro 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 Ef ciency Linear Regulator characteristics). n Post Regulator for Switching Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and VLDO n Low Parts Count Variable Voltage Supply and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the n property of their respective owners. Low Output Voltage Power Supplies TYPICAL APPLICATION Variable Output Voltage 500mA Supply N = 1676 IN LT3085 V IN 1.2V TO 36V V CONTROL + 1F OUT V OUT SET 2.2F R SET V = R 10A OUT SET 9.80 9.90 10.00 10.10 10.20 3085 TA01a SET PIN CURRENT DISTRIBUTION (A) 3085 TA01b 3085fb 1LT3085 (Note 1) All Voltages Relative to V ABSOLUTE MAXIMUM RATINGS OUT V Pin Voltage ..................................... 40V, 0.3V Operating Junction Temperature Range (Notes 2, 10) CONTROL IN Pin Voltage ................................................ 40V, 0.3V E, I Grade ........................................... 40C to 125C SET Pin Current (Note 7) .................................... 15mA MP Grade ........................................... 55C to 125C SET Pin Voltage (Relative to OUT) ..........................10V Storage Temperature Range ................... 65C to 150C Output Short-Circuit Duration .......................... Inde nite Lead Temperature (Soldering, 10 sec) MS8E Package Only .......................................... 300C PIN CONFIGURATION TOP VIEW TOP VIEW OUT 1 6 IN OUT 1 8 IN OUT 2 7 IN OUT 7 5 IN 9 2 OUT 3 6 NC SET 4 5 V CONTROL SET 4 V 3 CONTROL MS8E PACKAGE 8-LEAD PLASTIC MSOP DCB PACKAGE 6-LEAD (2mm s 3mm) PLASTIC DFN T = 125C, = 60C/W, = 10C/W JMAX JA JC EXPOSED PAD (PIN 9) IS OUT, MUST BE SOLDERED TO V ON PCB OUT T = 125C, = 73C/W, = 10.6C/W JMAX JA JC SEE THE APPLICATIONS INFORMATION SECTION EXPOSED PAD (PIN 7) IS OUT, MUST BE SOLDERED TO V ON PCB OUT SEE THE APPLICATIONS INFORMATION SECTION ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3085EDCB PBF LT3085EDCB TRPBF LDQQ 40C to 125C 6-Lead (2mm 3mm) Plastic DFN LT3085EMS8E PBF LT3085EMS8E TRPBF LTDQP 8-Lead Plastic MSOP 40C to 125C LT3085IDCB PBF LT3085IDCB TRPBF LDQQ 6-Lead (2mm 3mm) Plastic DFN 40C to 125C LT3085IMS8E PBF LT3085IMS8E TRPBF LTDQP 8-Lead Plastic MSOP 40C to 125C LT3085MPMS8E PBF LT3085MPMS8E TRPBF LTDWQ 8-Lead Plastic MSOP 55C to 125C LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3085EDCB LT3085EDCB TR LDQQ 40C to 125C 6-Lead (2mm 3mm) Plastic DFN LT3085EMS8E LT3085EMS8E TR LTDQP 8-Lead Plastic MSOP 40C to 125C LT3085IDCB LT3085IDCB TR LDQQ 6-Lead (2mm 3mm) Plastic DFN 40C to 125C LT3085IMS8E LT3085IMS8E TR LTDQP 8-Lead Plastic MSOP 40C to 125C LT3085MPMS8E LT3085MPMS8E TR 8-Lead Plastic MSOP 55C to 125C LTDWQ Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. For more information on lead free part marking, go to: