LM3940T

Bay Linear Inspire the Linear Power 1.25A High Current Low Dropout Voltage Regulator for Convert 5V & 3.3V LM3940 Description The Bay Linear LM3940 is a 1.25A high accuracy, low dropout voltage regulator with only 40mV at light loads and 350mV(Typ.)@ 1.0A) and low quiescent current of 240µA typical. The LM3940 is designed for low voltage a application that requires lower dropout voltage and faster transient response. This device is an excellent choice for use in powering low voltage applications where require a lower dropout, faster transient response to regulate from +2.5V to 3.8V supplies and as a post regulator for switching supplies applications. The LM3940 offers full protection against over-current faults, reversed input polarity, reversed load insertion, and positive and negative transient voltage. On-Chip trimming adjusts the reference voltage to 1%. The LM3940 are offered in a 3-pin SOT-223, TO-220 & TO-263 package compatible with other 3 terminal regulators. The LM3940 is also offer in a new LPDD (Low Profile TO-263) package from 4.47 mm (DD) tickness down to only 1.27 mm (LPDD) total tickness. Features • • • • • • • • • High output accuracy of 1% Fix Output 5.0v & 3.3V Output Current of 1.25A Low Dropout Voltage Low quiescent current Extremely Tight Load & Line Regulation Reverse-battery and “Load Dump” Protection Zero Current Shutdown Mode (5-pin version) Offer in TO-263, TO-252, TO-220, SOT-223, & New Slim LPDD Similar to industry Standard LM3940 • Applications • • • • • • • Powering VGA & Sound Card LCD Monitor Battery Powered Equipments/Laptop & Notebook SMPS Post Regulator / DC to DC Modules High Efficiency Linear Power Supply Adjustable Power Supply Bar Code Scanners Pin Connection Ordering Information Devices LM3940T LM3940S LM3940D LM3940N LM3940J XX=Output Voltage Package TO-220-3 TO-263-3 TO-252 SOT-223-3 LPDD-3 Temp. -40 °C to 125 °C -40 °C to 125 °C -40 °C to 125 °C -40 °C to 125 °C -40 °C to 125 °C Bay Linear, Inc 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com LM3940 ABSOLUTE MAXIMUM RATINGS Lead Temp. (Soldering, 5 Seconds).................................260°C Storage Temperature Range.............................. -65° to +150°C Operating Junction Temperature Range LM3940 Control Section........................... -45°C +125°C LM3940 Power Transistor..........................-45°C +150°C Input Voltage ........................................................26V Maximum Output Current....................................3.5A Input Supply Voltage (Survival) .......... -20V to +60V ELECTRICAL CHARACTERISTICS PARAMETER Output Voltage Output Voltage Line Regulation Load Regulation Dropout Voltage 5mA≤IL≤1.25A 5mA≤IL≤1.25A IOUT = 5mA, V IN =V OUT + 1V, I l = 1250mA, C L = 10µF. Ta=25°C, unless otherwise specified. CONDITIONS Typ Min 3.3 3.3 5.0 5.0 20 35 120 400 500 240 22 35 1.7 1.7 400 260 1.2 1.5 3.267 3.234 4.95 4.90 LM3940 Max 3.330 3.366 5.05 5.10 40 50 180 600 800 350 35 70 Units V V mV mV mV IO = 5mA, 4.5V≤VIN ≤5.5V 50mA ≤ IOUT≤ 1.25 A IO = 5mA IO = 1000mA IO = 1250mA Quiescent Current Short Circuit Current Current Limit Output Noise Voltage (10Hz to 100kHz) IL = 100mA IO = 5mA, VIN = VOUT, +1V IO = 1000mA, VIN = VOUT, +1V IO = 1.25A RL = 0 VOUT = 0V (Note 4) CL = 10µF CL = 33µF µA mA A A µV RMS BLOCK DIAGRAM Bay Linear, Inc 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com Advance Information- These data sheets contain descriptions of products that are in development. The specifications are based on the engineering calculations, computer simulations and/ or initial prototype evaluation. Preliminary Information- These data sheets contain minimum and maximum specifications that are based on the initial device characterizations. These limits are subject to change upon the completion of the full characterization over the specified temperature and supply voltage ranges. The application circuit examples are only to explain the representative applications of the devices and are not intended to guarantee any circuit design or permit any industrial property right to other rights to execute. Bay Linear takes no responsibility for any problems related to any industrial property right resulting from the use of the contents shown in the data book. Typical parameters can and do vary in different applications. Customer’s technical experts must validate all operating parameters including “ Typical” for each customer application. LIFE SUPPORT AND NUCLEAR POLICY Bay Linear products are not authorized for and should not be used within life support systems which are intended for surgical implants into the body to support or sustain life, in aircraft, space equipment, submarine, or nuclear facility applications without the specific written consent of Bay Linear President. Bay Linear, Inc 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com