LT3055 Series 500mA, Linear Regulator with Precision Current Limit and Diagnostics FEATURES DESCRIPTION n Output Current: 500mA The LT 3055 series are micropower, low noise, low dropout n Dropout Voltage: 350mV voltage (LDO) linear regulators. The devices supply 500mA n Input Voltage Range: 1.8V to 45V of output current with a dropout voltage of 350mV. A 10nF n Programmable Precision Current Limit: 10% bypass capacitor reduces output noise to 25V in a RMS n Output Current Monitor: 1/500th of I 10Hz to 100kHz bandwidth and soft starts the reference. OUT n Programmable Minimum I Monitor The LT3055s 45V input voltage rating combined with its OUT n Temperature Monitor: 10mV/C precision current limit and diagnostic functions make the n FAULT Indicator: Current Limit, Thermal Limit or IC an ideal choice for robust, high reliability applications. Minimum I OUT A single resistor programs the LT3055s current limit, ac- n Low Noise: 25V (10Hz to 100kHz) RMS curate to 10% over a wide input voltage and temperature n Adjustable Output (V = V = 0.6V) REF OUT(MIN) range. Another resistor programs the LT3055s minimum n Output Tolerance: 2% Over Load, Line and Temperature output current monitor, useful for detecting open-circuit n Stable with Low ESR, Ceramic Output Capacitors conditions. The current monitor function sources a current (3.3F Minimum) equal to 1/500th of output current. Logic fault pins assert n Shutdown Current: <1A low if the LT3055 is in current limit (FAULT2), operating n Reverse Battery and Thermal Limit Protection below its minimum output current (FAULT1) or is in thermal n 16-Lead 4mm 3mm DFN and MSOP Packages limit (both FAULT1 and FAULT2). PWRGD indicates output regulation. The TEMP pin indicates average die temperature. APPLICATIONS The LT3055 optimizes stability and transient response n Protected Antenna Supplies with low ESR ceramic capacitors, requiring a minimum of n Automotive Telematics 3.3F. Internal protection circuitry includes current limit- n Industrial Applications (Trucks, Forklifts, etc.) ing, thermal limiting, reverse battery protection, reverse n High Reliability Applications current protection and reverse output protection. n Noise-Sensitive RF or DSP Supplies The LT3055 is available in fixed output voltages of 3.3V L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property and 5V, and as an adjustable device with an output voltage of their respective owners. range from 0.6V to 40V. TYPICAL APPLICATION Precision Current Limit, R = 604 IMAX 550 V = 5V 5V Supply with 497mA Precision Current Limit, 10mA I OUT(NOMINAL) MIN 540 LT3055-5 530 IN OUT 5V + 520 V IN 10F 10nF 10F 200k 200k 200k SHDN SENSE 6V 510 FAULT1 V = 7V IN 500 FAULT2 ADJ PWRGD 490 TO V = 5.6V IN I I P MAX MON 480 1k ADC 604 0.1F 22nF (ADC (THRESHOLD = 497mA) 470 FULL-SCALE = 1V) TO 460 TEMP P 450 ADC I MIN REF/BYP 75 50 25 0 25 50 75 100 125 150 175 120k GND 10nF 0.1F TEMPERATURE (C) (THRESHOLD = 10mA) 3055 TA01a 3055 TA01b 3055fa 1 For more information www.linear.com/LT3055 CURRENT LIMIT FAULT THRESHOLD (mA)LT3055 Series ABSOLUTE MAXIMUM RATINGS (Note 1) IN Pin Voltage .........................................................50V TEMP Pin Voltage ............................................0.3V, 7V OUT Pin Voltage ........................................... +40V, 50V REF/BYP Pin Voltage ...................................................1V Input-to-Output Differential Voltage ..............+50V, 40V Output Short-Circuit Duration .......................... Indefinite ADJ Pin Voltage ......................................................50V Operating Junction Temperature Range (Notes 2, 3) SENSE Pin Voltage ..................................................50V E-, I-Grades ....................................... 40C to 125C SHDN Pin Voltage ...................................................50V MP-Grade .......................................... 55C to 150C FAULT1, FAULT2, PWRGD Pin Voltage ............0.3V, 50V H-Grade ............................................. 40C to 150C I Pin Voltage ..............................................0.3V, 7V Storage Temperature Range .................. 65C to 150C MON I Pin Voltage ...............................................0.3V, 7V Lead Temperature: (Soldering, 10 sec) MIN I Pin Voltage ..............................................0.3V, 7V MSOP Package Only .........................................300C MAX PIN CONFIGURATION TOP VIEW TOP VIEW IN 1 16 OUT IN 1 16 OUT IN 2 15 OUT IN 2 15 OUT SHDN 3 14 ADJ/SENSE** SHDN 3 14 ADJ/SENSE** FAULT1 4 17 13 GND/ADJ* FAULT1 4 13 GND/ADJ* 17 FAULT2 5 12 GND GND GND FAULT2 5 12 GND PWRGD 6 11 REF/BYP TEMP 7 10 I PWRGD 6 11 REF/BYP MAX I 8 9 I MON MIN TEMP 7 10 I MAX MSE PACKAGE I 8 9 I MON MIN 16-LEAD PLASTIC MSOP T = 125C, = 37C/W, = 5C/W TO 10C/W DE PACKAGE JMAX JA JC T = 150C FOR H-GRADE 16-LEAD (4mm 3mm) PLASTIC DFN JMAX EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB T = 125C, = 38C/W, = 4.3C/W JMAX JA JC EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB *PIN 13 IS GND FOR LT3055 PIN 13 IS ADJ FOR LT3055-3.3 AND LT3055-5. **PIN 14 IS ADJ FOR LT3055 PIN 14 IS SENSE FOR LT3055-3.3 AND LT3055-5. 3055fa 2 For more information www.linear.com/LT3055