LM2940T

LM2940/LM2940C 1A Low Dropout Regulator January 2007 LM2940/LM2940C 1A Low Dropout Regulator General Description The LM2940/LM2940C positive voltage regulator features the ability to source 1A of output current with a dropout voltage of typically 0.5V and a maximum of 1V over the entire temperature range. Furthermore, a quiescent current reduction circuit has been included which reduces the ground current when the differential between the input voltage and the output voltage exceeds approximately 3V. The quiescent current with 1A of output current and an input-output differential of 5V is therefore only 30 mA. Higher quiescent currents only exist when the regulator is in the dropout mode (VIN − VOUT ≤ 3V). Designed also for vehicular applications, the LM2940/ LM2940C and all regulated circuitry are protected from reverse battery installations or 2-battery jumps. During line transients, such as load dump when the input voltage can momentarily exceed the specified maximum operating voltage, the regulator will automatically shut down to protect both the internal circuits and the load. The LM2940/LM2940C cannot be harmed by temporary mirror-image insertion. Familiar regulator features such as short circuit and thermal overload protection are also provided. Features ■ ■ ■ ■ ■ ■ ■ Dropout voltage typically 0.5V @IO = 1A Output current in excess of 1A Output voltage trimmed before assembly Reverse battery protection Internal short circuit current limit Mirror image insertion protection P+ Product Enhancement tested Typical Application 882203 *Required if regulator is located far from power supply filter. **COUT must be at least 22 μF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to the regulator. This capacitor must be rated over the same operating temperature range as the regulator and the ESR is critical; see curve. Ordering Information Temp Range 0°C Output Voltage 5.0 LM2940CT-5.0 LM2940CS-5.0 LM2940CSX -5.0 8.0 – – – 9.0 LM2940CT-9.0 LM2940CS-9.0 LM2940CSX -9.0 10 – – – 12 LM2940CT-12 LM2940CS-12 LM2940CSX -12 15 LM2940CT-15 LM2940CS-15 LM2940CSX -15 TO-263 Package TO-220 ≤ TJ ≤ 125°C LM2940LD-5.0 −40°C LM2940LD-8.0 LM2940LD-9.0 LM2940LD-10 LM2940LD-12 LLP 1k Units LM2940LD-15 Tape and Reel LLP 4.5k Units Tape and Reel TO-220 TO-263 ≤ TJ ≤ 125°C LM2940LDX -5.0 LM2940LDX -8.0 LM2940LDX -9.0 LM2940LDX -10 LM2940LDX -12 LM2940LDX -15 – – – −40°C LM2940T-5.0 LM2940S-5.0 LM2940SX-5.0 LM2940T-8.0 LM2940S-8.0 LM2940SX-8.0 LM2940T-9.0 LM2940S-9.0 LM2940SX-9.0 LM2940T-10 LM2940S-10 LM2940SX-10 LM2940T-12 LM2940S-12 LM2940SX-12 ≤ TJ ≤ 125°C © 2007 National Semiconductor Corporation 8822 www.national.com LM2940/LM2940C Temp Range −40°C Output Voltage 5.0 8.0 9.0 10 12 15 Package LM2940IMP-5.0 LM2940IMP-8.0 LM2940IMP-9.0 LM2940IMP-10 LM2940IMP-12 LM2940IMP-15 SOT-223 LM2940IMPX -5.0 L53B LM2940IMPX -8.0 L54B LM2940IMPX -9.0 L0EB LM2940IMPX -10 L55B LM2940IMPX -12 L56B LM2940IMPX -15 L70B SOT-223 in Tape and Reel ≤ TA ≤ 85°C Marking The physical size of the SOT-223 is too small to contain the full device part number. The package markings indicated are what will appear on the actual device. Mil-Aero Ordering Information Temperature Range −55°C Output Voltage 5.0 LM2940J-5.0/883 5962-8958701EA LM2940WG5.0/883 5962-8958701XA 8.0 – – 12 LM2940J-12/883 5962-9088401QEA LM2940WG5-12/883 15 LM2940J-15/883 5962-9088501QEA LM2940WG5-15/883 Package J16A WG16A ≤ TJ ≤ 125°C For information on military temperature range products, please go to the Mil/Aero Web Site at http://www.national.com/appinfo/milaero/index.html. Connection Diagrams TO-220 (T) Plastic Package SOT-223 (MP) 3-Lead 882202 Front View See NS Package Number TO3B 16-Lead Dual-in-Line Package (J) 882242 Front View See NS Package Number MP04A 16-Lead Ceramic Surface-Mount Package (WG) 882243 882244 Top View See NS Package Number J16A TO-263 (S) Surface-Mount Package Top View See NS Package Number WG16A LLP (LD) 8-Lead 882211 Top View 882212 882246 Side View See NS Package Number TS3B Pin 2 and pin 7 are fused to center DAP Pin 5 and 6 need to be tied together on PCB board Top View See NS Package Number LDC08A www.national.com 2 LM2940/LM2940C Absolute Maximum Ratings (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. LM2940S, J, WG, T, MP ≤ 100 ms LM2940CS, T ≤ 1 ms Internal Power Dissipation  (Note 2) Maximum Junction Temperature Storage Temperature Range Soldering Temperature (Note 3) TO-220 (T), Wave TO-263 (S) 60V 45V Internally Limited 150°C −65°C ≤ TJ ≤ +150°C 260°C, 10s 235°C, 30s SOT-223 (MP) LLP-8 (LD) ESD Susceptibility (Note 4) 260°C, 30s 235°C, 30s 2 kV (Note 1) 26V −40°C ≤ TJ ≤ 125°C Operating Conditions Input Voltage Temperature Range LM2940T, LM2940S LM2940CT, LM2940CS LM2940IMP LM2940J, LM2940WG LM2940LD −55°C ≤ TJ ≤ 125°C −40°C ≤ TJ ≤ 125°C −40°C ≤ TA ≤ 85°C 0°C ≤ TJ ≤ 125°C Electrical Characteristics VIN = VO + 5V, IO = 1A, CO = 22 μF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25°C. Output Voltage (VO) Parameter Conditions Typ 5V LM2940 Limit (Note 5) 4.85/4.75 5.15/5.25 Line Regulation Load Regulation VO + 2V ≤ VIN ≤ 26V, IO = 5 mA 50 mA ≤ IO ≤ 1A LM2940, LM2940/883 LM2940C Output Impedance Quiescent Current 100 mADC and 20 mArms, fO = 120 Hz VO +2V ≤ VIN ≤ 26V, IO = 5 mA LM2940, LM2940/883 LM2940C VIN = VO + 5V, IO = 1A Output Noise Voltage Ripple Rejection 10 Hz − 100 kHz, IO = 5 mA fO = 120 Hz, 1 Vrms, IO = 100 mA LM2940 LM2940C fO = 1 kHz, 1 Vrms, IO = 5 mA Long Term Stability Dropout Voltage IO = 1A IO = 100 mA 20 0.5 110 0.8/1.0 150/200 0.7/1.0 150/200 32 0.5 110 0.8/1.0 150/200 0.7/1.0 150/200 mV/ 1000 Hr VMAX mVMAX 72 72 60/54 60 60/50 66 66 54/48 54 54/48 dBMIN dBMIN 150 700/700 240 1000/1000 μVrms 10 10 30 15/20 15 45/60 50/60 30 45/60 50/60 mAMAX 15/20 10 15/20 15/20 mAMAX 35 35 35 50/80 50 1000/1000 50/100 55 55 55 80/130 80 1000/1000 mΩ 80/130 mVMAX 20 50 LM2940/883 Limit (Note 6) 4.85/4.75 5.15/5.25 40/50 20 Typ 8V LM2940 Limit (Note 5) 7.76/7.60 8.24/8.40 80 LM2940/883 Limit (Note 6) 7.76/7.60 8.24/8.40 50/80 Units 6.25V ≤ VIN ≤ 26V Output Voltage 5 mA ≤ IO ≤ 1A 5.00 8.00 9.4V ≤ VIN ≤ 26V VMIN VMAX mVMAX 3 www.national.com LM2940/LM2940C Output Voltage (VO) Parameter Short Circuit Current Maximum Line Transient Conditions (Note 7) RO = 100Ω LM2940, T ≤ 100 ms LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms Reverse Polarity DC Input Voltage Reverse Polarity Transient Input Voltage RO = 100Ω LM2940, LM2940/883 LM2940C RO = 100Ω LM2940, T ≤ 100 ms LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms −55 −75 −30 −30 55 45 75 Typ 5V LM2940 Limit (Note 5) 1.6 LM2940/883 Limit (Note 6) 1.5/1.3 Typ 8V LM2940 Limit (Note 5) 1.6 LM2940/883 Limit (Note 6) 1.6/1.3 Units 1.9 1.9 AMIN 60/60 40/40 75 55 −15/−15 −30 −30 −75 −45/−45 60/60 40/40 45 −15/−15 −15 −50/−50 −45/−45 −15/−15 VMIN −15/−15 −15 −50/−50 −45/−45 VMIN VMIN Electrical Characteristics VIN = VO + 5V, IO = 1A, CO = 22 μF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25°C. Output Voltage (VO) Parameter Conditions Typ 9V LM2940 Limit (Note 5) 8.73/8.55 9.27/9.45 Line Regulation Load Regulation VO + 2V ≤ VIN ≤ 26V, IO = 5 mA 50 mA ≤ IO ≤ 1A LM2940 LM2940C Output Impedance 100 mADC and 20 mArms, fO = 120 Hz Quiescent Current VO +2V ≤ VIN < 26V, IO = 5 mA LM2940 LM2940C VIN = VO + 5V, IO = 1A Output Noise Voltage Ripple Rejection 10 Hz − 100 kHz, IO = 5 mA fO = 120 Hz, 1 Vrms, IO = 100 mA LM2940 LM2940C Long Term Stability 64 64 34 52/46 52 36 mV/ 1000 Hr 63 51/45 dBMIN 10 10 30 270 15/20 15 45/60 30 300 45/60 mAMAX μVrms 10 15/20 mAMAX 60 60 60 90/150 90 65 mΩ 65 100/165 mVMAX 20 90 20 Typ 10V LM2940 Limit (Note 5) 9.70/9.50 10.30/10.50 100 Units 10.5V ≤ VIN ≤ 26V Output Voltage 5 mA ≤ IO ≤1A 9.00 11.5V ≤ VIN ≤ 26V 10.00 VMIN VMAX mVMAX www.national.com 4 LM2940/LM2940C Output Voltage (VO) Parameter Dropout Voltage Short Circuit Current Maximum Line Transient RO = 100Ω T ≤ 100 ms LM2940 LM2940C Reverse Polarity DC Input Voltage Reverse Polarity Transient Input Voltage RO = 100Ω LM2940 LM2940C RO = 100Ω T ≤ 100 ms LM2940 LM2940C −75 −55 −30 −30 75 55 IO = 1A IO = 100 mA (Note 7) Conditions Typ 0.5 110 1.9 9V LM2940 Limit (Note 5) 0.8/1.0 150/200 1.6 Typ 0.5 110 1.9 10V LM2940 Limit (Note 5) 0.8/1.0 150/200 1.6 Units VMAX mVMAX AMIN 60/60 45 −15/−15 −15 75 60/60 VMIN −30 −15/−15 VMIN −50/−50 −45/−45 −75 −50/−50 VMIN Electrical Characteristics VIN = VO + 5V, IO = 1A, CO = 22 μF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25°C. Output Voltage (VO) Parameter Conditions Typ 12V LM2940 Limit (Note 5) 11.64/11.40 12.36/12.60 Line Regulation Load Regulation VO + 2V ≤ VIN ≤ 26V, IO = 5 mA 50 mA ≤ IO ≤ 1A LM2940, LM2940/883 LM2940C Output Impedance Quiescent Current 100 mADC and 20 mArms, fO = 120 Hz VO +2V ≤ VIN ≤ 26V, IO = 5 mA LM2940, LM2940/883 LM2940C VIN = VO + 5V, IO = 1A Output Noise Voltage 10 Hz − 100 kHz, IO = 5 mA 10 10 30 360 15/20 15 45/60 50/60 1000/1000 15/20 10 30 450 15 45/60 50/60 1000/1000 mAMAX μVrms 15/20 mAMAX 55 55 80 120/200 120 1000/1000 120/190 70 100 150 1000/1000 mΩ 150/240 mVMAX 20 120 LM2940/833 Limit (Note 6) 11.64/11.40 12.36/12.60 75/120 20 Typ 15V LM2940 Limit (Note 5) 14.55/14.25 15.45/15.75 150 LM2940/833 Limit (Note 6) 14.55/14.25 15.45/15.75 95/150 Units 13.6V ≤ VIN ≤ 26V Output Voltage 5 mA ≤ IO ≤1A 12.00 15.00 16.75V ≤ VIN ≤ 26V VMIN VMAX mVMAX 5 www.national.com LM2940/LM2940C Output Voltage (VO) Parameter Ripple Rejection Conditions fO = 120 Hz, 1 Vrms, IO = 100 mA LM2940 LM2940C fO = 1 kHz, 1 Vrms, IO = 5 mA Long Term Stability Dropout Voltage Short Circuit Current Maximum Line Transient IO = 1A IO = 100 mA (Note 7) RO = 100Ω LM2940, T ≤ 100 ms LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms Reverse Polarity DC Input Voltage Reverse Polarity Transient Input Voltage RO = 100Ω LM2940, LM2940/883 LM2940C RO = 100Ω LM2940, T ≤ 100 ms LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms −55 −75 −30 −30 55 45 75 48 0.5 110 1.9 66 66 Typ 12V LM2940 Limit (Note 5) LM2940/833 Limit (Note 6) Typ 15V LM2940 Limit (Note 5) LM2940/833 Limit (Note 6) Units 54/48 54 52/46 60 0.8/1.0 150/200 1.6 0.7/1.0 150/200 1.6/1.3 0.5 110 1.9 0.8/1.0 150/200 1.6 0.7/1.0 150/200 1.6/1.3 64 52 48/42 dBMIN dBMIN mV/ 1000 Hr VMAX mVMAX AMIN 60/60 40/40 55 −15/−15 −30 −15 45 −15/−15 VMIN 40/40 VMIN −15/−15 −15 −50/−50 −45/−45 −45/−45 −55 −45/−45 −45/−45 VMIN Thermal Performance Thermal Resistance Junction-to-Case, θ(JC) Thermal Resistance Junction-to-Ambient, θ(JA) 3-Lead TO-220 3-Lead TO-263 3-Lead TO-220 (Note 2) 3-Lead TO-263 (Note 2) SOT-223(Note 2) 8-Lead LLP (Note 2) 4 4 60 80 174 35 °C/W °C/W Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Conditions are conditions under which the device functions but the specifications might not be guaranteed. For guaranteed specifications and test conditions see the Electrical Characteristics. Note 2: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ, the junction-to-ambient thermal resistance, θJA, and the ambient temperature, TA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. The value of θJA (for devices in still air with no heatsink) is 60°C/W for the TO-220 package, 80°C/W for the TO-263 package, and 174°C/W for the SOT-223 package. The effective value of θJA can be reduced by using a heatsink (see Application Hints for specific information on heatsinking). The value of θJA for the LLP package is specifically dependent on PCB trace area, trace material, and the number of layers and thermal vias. For improved thermal resistance and power dissipation for the LLP package, refer to Application Note AN-1187. It is recommended that 6 vias be placed under the center pad to improve thermal performance. Note 3: Refer to JEDEC J-STD-020C for surface mount device (SMD) package reflow profiles and conditions. Unless otherwise stated, the temperature and time are for Sn-Pb (STD) only. Note 4: ESD rating is based on the human body model, 100 pF discharged through 1.5 kΩ. Note 5: All limits are guaranteed at TA = TJ = 25°C only (standard typeface) or over the entire operating temperature range of the indicated device (boldface type). All limits at TA = TJ = 25°C are 100% production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control methods. Note 6: All limits are guaranteed at TA = TJ = 25°C only (standard typeface) or over the entire operating temperature range of the indicated device (boldface type). All limits are 100% production tested and are used to calculate Outgoing Quality Levels. Note 7: Output current will decrease with increasing temperature but will not drop below 1A at the maximum specified temperature. www.national.com 6 LM2940/LM2940C Typical Performance Characteristics Dropout Voltage Dropout Voltage vs. Temperature 882213 882214 Output Voltage vs. Temperature Quiescent Current vs. Temperature 882215 882216 Quiescent Current Quiescent Current 882217 882218 7 www.national.com LM2940/LM2940C Line Transient Response Load Transient Response 882219 882220 Ripple Rejection Low Voltage Behavior 882221 882225 Low Voltage Behavior Low Voltage Behavior 882226 882227 www.national.com 8 LM2940/LM2940C Low Voltage Behavior Low Voltage Behavior 882228 882229 Low Voltage Behavior Output at Voltage Extremes 882230 882231 Output at Voltage Extremes Output at Voltage Extremes 882232 882233 9 www.national.com LM2940/LM2940C Output at Voltage Extremes Output at Voltage Extremes 882234 882235 Output at Voltage Extremes Output Capacitor ESR 882236 882206 Peak Output Current Output Impedance 882208 882222 www.national.com 10 LM2940/LM2940C Maximum Power Dissipation (TO-220) Maximum Power Dissipation (SOT-223) 882224 882223 Maximum Power Dissipation (TO-263) 882210 11 www.national.com LM2940/LM2940C Equivalent Schematic Diagram 882201 www.national.com 12 LM2940/LM2940C Application Information EXTERNAL CAPACITORS The output capacitor is critical to maintaining regulator stability, and must meet the required conditions for both ESR (Equivalent Series Resistance) and minimum amount of capacitance. MINIMUM CAPACITANCE: The minimum output capacitance required to maintain stability is 22 μF (this value may be increased without limit). Larger values of output capacitance will give improved transient response. ESR LIMITS: The ESR of the output capacitor will cause loop instability if it is too high or too low. The acceptable range of ESR plotted versus load current is shown in the graph below. It is essential that the output capacitor meet these requirements, or oscillations can result. temperature must be within the range specified under Absolute Maximum Ratings. To determine if a heatsink is required, the power dissipated by the regulator, PD, must be calculated. The figure below shows the voltages and currents which are present in the circuit, as well as the formula for calculating the power dissipated in the regulator: 882237 IIN = IL + IG PD = (VIN − VOUT) IL + (VIN) IG Output Capacitor ESR FIGURE 2. Power Dissipation Diagram The next parameter which must be calculated is the maximum allowable temperature rise, TR(MAX). This is calculated by using the formula: TR(MAX) = TJ(MAX) − TA(MAX) where: TJ(MAX) is the maximum allowable junction temperature, which is 125°C for commercial grade parts. TA(MAX) is the maximum ambient temperature which will be encountered in the application. Using the calculated values for TR(MAX) and PD, the maximum allowable value for the junction-to-ambient thermal resistance, θ(JA), can now be found: θ(JA) = TR(MAX) / PD IMPORTANT: If the maximum allowable value for θ(JA) is found to be ≥ 53°C/W for the TO-220 package, ≥ 80°C/W for the TO-263 package, or ≥ 174°C/W for the SOT-223 package, no heatsink is needed since the package alone will dissipate enough heat to satisfy these requirements. If the calculated value for θ(JA)falls below these limits, a heatsink is required. HEATSINKING TO-220 PACKAGE PARTS The TO-220 can be attached to a typical heatsink, or secured to a copper plane on a PC board. If a copper plane is to be used, the values of θ(JA) will be the same as shown in the next section for the TO-263. If a manufactured heatsink is to be selected, the value of heatsink-to-ambient thermal resistance, θ(H−A), must first be calculated: θ(H−A) = θ(JA) − θ(C−H) − θ(J−C) Where: θ(J−C) is defined as the thermal resistance from the junction to the surface of the case. A value of 3°C/W can be assumed for θ(J−C) for this calculation. 882206 FIGURE 1. ESR Limits It is important to note that for most capacitors, ESR is specified only at room temperature. However, the designer must ensure that the ESR will stay inside the limits shown over the entire operating temperature range for the design. For aluminum electrolytic capacitors, ESR will increase by about 30X as the temperature is reduced from 25°C to −40° C. This type of capacitor is not well-suited for low temperature operation. Solid tantalum capacitors have a more stable ESR over temperature, but are more expensive than aluminum electrolytics. A cost-effective approach sometimes used is to parallel an aluminum electrolytic with a solid Tantalum, with the total capacitance split about 75/25% with the Aluminum being the larger value. If two capacitors are paralleled, the effective ESR is the parallel of the two individual values. The “flatter” ESR of the Tantalum will keep the effective ESR from rising as quickly at low temperatures. HEATSINKING A heatsink may be required depending on the maximum power dissipation and maximum ambient temperature of the application. Under all possible operating conditions, the junction 13 www.national.com LM2940/LM2940C    θ(C−H) is defined as the thermal resistance between the case and the surface of the heatsink. The value of θ(C−H) will vary from about 1.5°C/W to about 2.5°C/W (depending on method of attachment, insulator, etc.). If the exact value is unknown, 2°C/W should be assumed for θ(C −H). When a value for θ(H−A) is found using the equation shown, a heatsink must be selected that has a value that is less than or equal to this number. θ(H−A) is specified numerically by the heatsink manufacturer in the catalog, or shown in a curve that plots temperature rise vs power dissipation for the heatsink. HEATSINKING TO-263 PACKAGE PARTS The TO-263 (“S”) package uses a copper plane on the PCB and the PCB itself as a heatsink. To optimize the heat sinking ability of the plane and PCB, solder the tab of the package to the plane. Figure 3 shows for the TO-263 the measured values of θ(JA) for different copper area sizes using a typical PCB with 1 ounce copper and no solder mask over the copper area used for heatsinking. 882239 FIGURE 4. Maximum Power Dissipation vs. TA for the TO-263 Package HEATSINKING SOT-223 PACKAGE PARTS The SOT-223 (“MP”) packages use a copper plane on the PCB and the PCB itself as a heatsink. To optimize the heat sinking ability of the plane and PCB, solder the tab of the package to the plane. Figure 5 and Figure 6 show the information for the SOT-223 package. Figure 6 assumes a θ(JA) of 74°C/W for 1 square inch of 1 ounce copper and 51°C/W for 1 square inch of 2 ounce copper, with a maximum ambient temperature (TA) of 85°C and a maximum junction temperature (TJ) of 125°C. For techniques for improving the thermal resistance and power dissipation for the SOT-223 package, please refer to Application Note AN-1028. 882238 FIGURE 3. θ(JA) vs. Copper (1 ounce) Area for the TO-263 Package As shown in the figure, increasing the copper area beyond 1 square inch produces very little improvement. It should also be observed that the minimum value of θ(JA) for the TO-263 package mounted to a PCB is 32°C/W. As a design aid, Figure 4 shows the maximum allowable power dissipation compared to ambient temperature for the TO-263 device. This assumes a θ(JA) of 35°C/W for 1 square inch of 1 ounce copper and a maximum junction temperature (TJ) of 125°C. 882240 FIGURE 5. θ(JA) vs. Copper (2 ounce) Area for the SOT-223 Package www.national.com 14 LM2940/LM2940C HEATSINKING LLP PACKAGE PARTS The value of θJA for the LLP package is specifically dependent on PCB trace area, trace material, and the number of layers and thermal vias. It is recommended that a minimum of 6 thermal vias be placed under the center pad to improve thermal performance. For techniques for improving the thermal resistance and power dissipation for the LLP package, please refer to Application Note AN-1187. 882241 FIGURE 6. Maximum Power Dissipation vs. TA for the SOT-223 Package 15 www.national.com LM2940/LM2940C Physical Dimensions inches (millimeters) unless otherwise noted 3-Lead SOT-223 Package NS Package Number MP04A 16 Lead Dual-in-Line Package (J) See NS Package Number J16A www.national.com 16 LM2940/LM2940C 16 Lead Surface Mount Package (WG) See NS Package Number WG16A 3-Lead TO-220 Plastic Package (T) NS Package Number TO3B 17 www.national.com LM2940/LM2940C 3-Lead TO-263 Surface Mount Package (MP) NS Package Number TS3B 8-Lead LLP Order Number LM2940LD-5.0, LM2940LD-8.0, LM2940LD-9.0, LM2940LD-10, LM2940LD-12 or LM2940LD-15 NS Package Number LDC08A www.national.com 18 LM2940/LM2940C Notes 19 www.national.com LM2940/LM2940C 1A Low Dropout Regulator Notes THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS, IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS DOCUMENT. TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS. 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Copyright© 2007 National Semiconductor Corporation For the most current product information visit us at www.national.com National Semiconductor Americas Customer Support Center Email: new.feedback@nsc.com Tel: 1-800-272-9959 National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530-85-86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +49 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 National Semiconductor Asia Pacific Customer Support Center Email: ap.support@nsc.com National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: jpn.feedback@nsc.com Tel: 81-3-5639-7560 www.national.com