Bay Linear Linear Excellence LM2931 100mA Low Dropout Voltage Regulator Description Features The Bay Linear LM2931 are low power voltage regulators designed for a wide range of applications. They are an excellent choice for use in Battery Powered applications. The LM2931 feature low quiescent current (100 µA Typ.) and low dropout of only 60mV at light loads and 300mV (typ.) at 100mA. The LM2931 has tight initial tolerance of 0.5% typ., extremely good load and line regulation of 0.05% typ. and very low output temperature coefficient. The Bay Linear LM2931 is available as a fixed voltage regulator and as an adjustable regulator in TO-92 and 8SOIC packages. The Bay Linear LM2931 in an 8SOIC package has an adjustable output voltage from 3V to 24V, programmed with a pair of external resistor. The logic compatible shutdown enables the regulator to be switched ON and OFF. • • • • • • • • • • Applications • • • • • • Pin Connection Guaranteed 100mA Output Fixed Versions 3.3V, 50.V, 8.0 Very Low Quiescent Current Low Dropout Voltage Extremely Tight Load and Line Regulation Very Low Temperature Coefficient Current and Thermal Limiting Reverse Battery Protection of –20V Transient protection of 60V Output programmable from 3V to 24V Battery Powered Systems Portable instrumentation Notebooks Computers Potable Consumer Equipment Automotive electronics SMPS Post-Regulator Ordering Information TO-92 Package SOT-89 1 2 3 SOT-89 TO-92 8-SOIC BAY LM2931 OUTPUT INPUT GND OUTPUT INPUT GROUND Front View “XX” Voltage Selection Guide Bottom View 8SOIC (M) Output 1 8 Input GND 2 7 GND GND 3 6 GND Feedback 4 5 Bay Linear, Inc Tolerance LM2931R-XX LM2931Z-XX LM2931M-XX Shutdown Vout 3.3V 5.0V 8.0V 8.5V 9.0V 10.0V 12.0V 15.0V Adjustable XX Code 33 50 80 85 90 10 12 15 Left Blank 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com LM2931 Absolute Maximum Rating Parameter Power Dissipation Lead Temperature ( Soldering 5 seconds ) Storage Temperature Range Operating Junction Temperature Input Supply Voltage Internally Limited 260 °C -65 °C to +150 °C -55 °C to +150 °C -20 to +35V Electrical Characteristics TJ = 25°C , IO = 100µA, VIN = 14V ( for 2931-15 VIN = 16V), CO = 100µF; unless otherwise specified) Parameter Conditions MIN TYP MAX Output Voltage (Fixed Version) -25 °C ≤ Tj ≤ 85 °C Full Operating Temperature 0.985 [ Vo ] Output Voltage (Fixed Version) 100µA ≤ IL ≤ 100mA, Tj ≤ T jmax 0.975 [Vo ] Input Supply Voltage Output Voltage Temperature Coefficient Line Regulation (Note 2) Load Regulation (Note 2) Dropout Voltage (Note 4) Ground Current (Note 5) Dropout Ground Current Current Limit Thermal Regulation (Note 6) Output Noise, 10Hz to 100KHz IL = 10mA Ripple Rejection Ratio 1.015 [ Vo ] Vo 1.025 [ Vo ] 26 150 0.98 [ Vo ] (Note 1) V 1.02 [ Vo ] 50 13V ≤ VIN ≤ 26V (Note 3) 100µA ≤ IL ≤ 100mA IL = 100µA IL = 100mA IL = 100µA IL = 10mA IL = 100mA VIN = (VOUT – 0.5V), IL = 100µA VOUT = 0 CL = 2.2µF CL = 3.3µF CL = 33µF IO = 10mA, f = 120Hz, C0 = 100µF VIN = VO + 3V+2Vpp Vo UNIT 0.1 0.1 60 300 100 0.9 8 110 160 0.05 500 350 120 0.4 0.3 200 600 150 1.5 12 170 200 0.2 60 V V ppm / ° C % % mV µA mA mA µA mA %/W µVrms dB 8 pin Versions only (LP2951) Reference Voltage Over Temperature (Note 7) Feedback Pin Bias Current Reference Voltage Temperature Coefficient Feedback Pin Bias Current Temperature Coefficient Shutdown Input Input Logic Voltage Shutdown Pin Input Current Regulator Output Current in Shutdown Bay Linear, Inc 1.21 1.185 1.235 20 50 (Note 1) 1.26 1.285 40 ηA ppm/°C ηA/°C 0.1 Low (Regulator ON) High (Regulator OFF) VS = 2.4V VS = 26V (Note 8) 5.0V ≤ VOUT ≤ 15.0V 3.3V ≤ VOUT ≤ 5.0V 2.0V ≤ VOUT ≤ 3.3V V 1.3 0.7 V 30 450 50 600 µA 2 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 10 20 30 µA www.baylinear.com LM2931 Note 1: Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range. Note 2: Unless otherwise specified all limits guaranteed for TJ = 25°C, VIN = VO +1V, IL = 100µA and CL = 1µF. Additional conditions for the 8pin versions are feedback tied to –XX Voltage tap and output tied to output Sense pin ( VOUT = XX V) and VSHUTDOWN ≤ 0.8V Note 2: Regulation is measured at constant junction temperature , using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under specification for thermal regulation. Note 3: Line regulation for is tested at 150°C for IL = 1mA. For IL = 100µA and TJ = 125°C, line regulation is guaranteed by design to 0.2%. for B2931-15 16V ≤ VIN ≤ 26V. Note 4: Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1V differential. Note 5: Ground pin Current is the regulator quiescent current. The total current drawn from the source is the sum of the ground pin current and output load current. Note 6: Thermal regulation is the change in output voltage at a time T after a change in power dissipation, excluding load or line regulation effects. Specifications are for a 50 mA load pulse (1.25W) for T = 10ms. Note 7: VREF ≤ VOUT ≤ (VIN –1V), 2.3V ≤ VIN ≤ 26V, 100µA ≤ IL ≤100mA, TJ ≤ TJMAX Note 8: VSHUTDOWN ≥ 2V, VIN ≤ 26V, VOUT = 0 Application Hints The LM2931 requires an output capacitor for device stability. The value required varies greatly depending upon the application circuit and other factors. The high frequency characteristics of electrolytic capacitors depend greatly on the type and also on the manufacturer. Sometimes only bench testing is the only means to determine the proper capacitor type and value. The high quality 100 µF aluminum electrolytic covers all general application circuits, this stability can be obtained with a tantalum electrolytic value of 47 µF. Another critical point of electrolytic characteristics is its performance over temperature. The LM2931 is designed to operate starting at -40°C which may not be true in the case of electrolytic. Higher temperatures generally no problem. The electrolytic. type in aluminum will freeze around -30°C. This could cause an oscillation at output of regulator. At a lower temperature requirement by many applications the capacitor should maintain its performance. So as a result, for an application which regulator junction temperature does not exceed 25°C, the output capacitor can be reduced by the Bay Linear, Inc factor of two over the value needed for the entire temperature range. Other points with linear regulators are that the twitch higher output current stability decreases. In most applications the LM2931 is operating at few milliamps. In these applications the output capacitance can be further reduced. For example, when the regulator is running at 10mA output current the output capacitance value is half compared to the same regulator that is running at 100 mA. With the LM2931 adjustable regulator, the minimum value of output capacitance is a function of the output voltage. The value decreases with higher output voltages, since the internal loop gain is reduced. The worst case occurs at the lower temperature and maximum operating currents, the entire circuit and the electrolytic, should be cooled down to the minimum temperature. The minimum of 0.6 volts required at the input of regulator above the output to keep the power dissipation and die heating to its minimum. After the value for the capacitor has been determined for actual use, the value should be doubled. 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com LM2931 TYPICAL CHARACTERISTICS 15 10 ~ ~ ~ ~ IO = 50mA 2 1 IO = 0mA 40 0 80 20 15 10 1.10 90 0 0.3 IO = 50mA IO = 10mA 0.1 80 800 0.5 500 0.4 0.3 0.2 120 50 3.0 2.0 14 12 10 ºC/W HEAT SINK 10 8 6 0.5 0.4 0.3 10 20 30 40 50 60 70 80 90 OPERATION DURING LOAD DUMP OUTPUT VOLTAGE (V) 1 0.1 0.2 0.1 0 0.01 Bay Linear, Inc 0.4" LENGTH FROMPC BOARD 0 OUTPUT VOLTAGE (V) 0.6 AMBIENT TEMPERATURE (ºC) 0.4 0.3 MAXIMUM POWER DISSIPATION Ω) OUTPUT IMPEDANCE (Ω) POWER DISSIPATION (W) 0.7 25 0.125" LEAD LENGTH FROM PC BOARD 0.5 AMBIENT TEMPERATURE (ºC) LM29315.0 IO = 10mA 0.9 20 0.6 AMBIENT TEMPERATURE (ºC) 10 15 0.7 0 MAXIMUM POWER DISSIPATION (SO8) 10 0.8 0.1 INPUT VOLTAGE (V) 0.8 30 30 0.2 NO HEAT SINK 0 10 20 30 40 50 60 70 80 90 100 1.0 20 0.9 0 5 10 MAXIMUM POWER DISSIPATION (TO-92) 2 0 TJ = -40ºC 1.0 16 6.0 24 INPUT VOLTAGE (V) 18 4 1.0 21 200 0 POWER DISSIPATION (W) POWER DISSIPATION (W) 4.0 18 TJ = 85ºC 300 100 INFINITE HEAT SINK 20 5.0 400 MAXIMUM POWER DISSIPATION (TO-220) 22 LM2931 5.0 IO = 100 mA 15 TJ = 25ºC OUTPUT CURRENT (mA) LOW VOLTAGE BEHAVIOR 5.0 12 0 0 6.0 9 100 0.1 JUNCTION TEMPERATURE (ºC) 4.0 6 PEAK OUTPUT CURRENT 0.6 0 3.0 3 OUTPUT VOLTAGE (V) OUTPUT CURRENT (mA) INPUT OUTPUT DIFFERENTIAL (V) INPUT OUTPUT DIFFERENTIAL (V) 60 DROPOUT VOLTAGE 0 OUTPUT VOLTAGE (V) 30 OUTPUT CURRENT (mA) IO = 100mA 2.0 1.18 1.16 0 0 0.5 40 1.22 1.20 1.14 DROPOUT VOLTAGE 0 1.26 1.24 5 120 0.6 0.2 1.28 25 JUNCTION TEMPERATURE (ºC) 0.4 LM2931CT ADJUSTABLE 1.12 0 -40 1.30 VIN = 14V REFERENCE VOLTAGE (V) 20 QUIESCENT CURRENT (mA) QUIESCENT CURRENT (mA) 30 3 REFERENCE VOLTAGE QUIESCENT CURRENT QUIESCENT CURRENT 25 0 30 60 90 120 150 70 60 50 40 30 20 10 0 ~ ~ 6 4 2 0 -2 -100 FREQUENCY (Hz) 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 ~ ~ CO = 100µF RL = 500W 0 100 200 300 400 500 TIME (ms) www.baylinear.com LM2931 TYPICAL APPLICATIONS LM2931 ADJUSTABLE OUTPUT LM2931 Fixed Output LM2931 LM2931 ADJ. SCHEMATIC DIAGRAM Bay Linear, Inc 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com LM2931 PACKAGE DRAWING TO-92(Z) 0.090 (2.286) Radius typ. 2 1 3 0.145 (3.683) 0.135 (3.429) 0.055 (1.397) 0.045 (1.143) 10° typ. BOTTOM VIEW 0.185 (4.699) 0.045 (1.143) 0.085 (2.159) Diameter 5° typ. 0.185 (4.699) 0.175 (4.445) 0.090 (2.286) typ. 5° typ. Seating Plane 0.025 (0.635) Max Uncontrolled Lead Diameter 0.500 (12.70) Min. 0.016 (0.406) 0.014 (0.356) 0.0155 (0.3937) 0.0145 (0.3683) 0.055 (1.397) 0.045 (1.143) 0.105 (2.667) 0.095 (2.413) Bay Linear, Inc 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 www.baylinear.com LM2931 PACKAGE DRAWING SO-8(M) 4.0 (0.158) 3.8 (0.150) 5.2 (0.205) 4.6 (0.181) 6.2 (0.244) 5.8 (0.228) Pin 1 1.27 (0.50) BSC 1.75 (0.069) 1.35 (0.053) 0.78 (0.031) 0.61 (0.024) 5.0 (0.197) 4.8 (0.188) 45° 0.37 (0.015) BSC 0.77 (0.030) 0.64 (0.025) 7 °(4 PLCS) 3 ° -6° 0.56 (0.022) 0.49 (0.019) 0.45 (0.018) 0.35 (0.014) Bay Linear, Inc 0.20 (0.008) 0.10 (0.004) 0.22 (0.009) 0.19 (0.007) 2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 989-7144, Fax: (925) 940-9556 7 ° (4 PLCS) www.baylinear.com LM2931 PACKAGE DRAWING SOT-89® C A J N P 2 1 3 K B F D G -T- STYLE 1 PIN 1. BASE 2. COLLECTOR 3. EMITTER STYLE 3 PIN 1. GATE 2. ANODE 3. CATHODE STYLE 2 PIN 1. ANODE 2. CATHODE 3. NO CONNECTION STYLE 4 PIN 1. DRAIN 2. GATE 3. SOURCE DIM A B C D E F G J K L N P MILLIMETERS MIN MAX 4.40 4.60 2.29 2.60 140 160 0.36 0.48 1.62 1.80 0.44 0.53 150 BSC 0.35 0.44 0.80 1.04 300 BSC 2.04 2.28 3.94 4.25 INCHES MIN MAX 0.174 0.181 0.091 0.102 0.056 0.062 0.015 0.018 0.064 0.070 0.018 0.020 0.059 BSC 0.014 0.017 0.032 0.040 0.118 BSC 0.081 0.089 0.156 0.167 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