LM2940,LM2940C LM2940/LM2940C 1A Low Dropout Regulator Literature Number: SNVS769H 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 volt- age, 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 ≤ TJ ≤ 125°C Output Voltage Package 5.0 8.0 9.0 10 12 15 LM2940CT-5.0 – LM2940CT-9.0 – LM2940CT-12 LM2940CT-15 LM2940CS-5.0 – LM2940CS-9.0 – LM2940CS-12 LM2940CS-15 – LM2940CSX -9.0 – LM2940CSX -12 LM2940CSX -15 LM2940CSX -5.0 LM2940LD-5.0 LM2940LD-8.0 LM2940LD-9.0 LM2940LD-10 LM2940LD-12 −40°C −40°C TO-263 LLP 1k Units LM2940LD-15 Tape and Reel ≤ TJ ≤ 125°C TO-220 LM2940LDX -5.0 LM2940LDX -8.0 LM2940LDX -9.0 LM2940LDX -10 LM2940LDX -12 LM2940LDX -15 LLP 4.5k Units Tape and Reel LM2940T-5.0 LM2940T-8.0 LM2940T-9.0 LM2940T-10 LM2940T-12 – TO-220 ≤ TJ ≤ LM2940S-5.0 LM2940S-8.0 LM2940S-9.0 LM2940S-10 LM2940S-12 – 125°C LM2940SX-5.0 LM2940SX-8.0 LM2940SX-9.0 LM2940SX-10 LM2940SX-12 – © 2007 National Semiconductor Corporation 8822 TO-263 www.national.com LM2940/LM2940C 1A Low Dropout Regulator January 2007 LM2940/LM2940C Temp Range −40°C ≤ TA ≤ Output Voltage 5.0 8.0 9.0 10 12 Package 15 LM2940IMP-5.0 LM2940IMP-8.0 LM2940IMP-9.0 LM2940IMP-10 LM2940IMP-12 LM2940IMP-15 SOT-223 85°C LM2940IMPX -5.0 LM2940IMPX -8.0 LM2940IMPX -9.0 LM2940IMPX -10 LM2940IMPX -12 LM2940IMPX -15 Marking L53B L54B L0EB L55B L56B L70B SOT-223 in Tape and Reel 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 ≤ TJ ≤ 125°C Output Voltage Package 5.0 8.0 12 15 LM2940J-5.0/883 5962-8958701EA – LM2940J-12/883 5962-9088401QEA LM2940J-15/883 5962-9088501QEA J16A LM2940WG5.0/883 5962-8958701XA – LM2940WG5-12/883 LM2940WG5-15/883 WG16A 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 882242 Front View See NS Package Number TO3B Front View See NS Package Number MP04A 16-Lead Dual-in-Line Package (J) 16-Lead Ceramic Surface-Mount Package (WG) 882243 882244 Top View See NS Package Number J16A Top View See NS Package Number WG16A TO-263 (S) Surface-Mount Package LLP (LD) 8-Lead 882211 Top View 882246 882212 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 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 Operating Conditions 60V LM2940CS, T ≤ 1 ms Internal Power Dissipation 260°C, 30s 235°C, 30s 2 kV Input Voltage Temperature Range 45V 26V −40°C ≤ TJ ≤ 125°C LM2940T, LM2940S (Note 2) Maximum Junction Temperature Storage Temperature Range 0°C ≤ TJ ≤ 125°C LM2940CT, LM2940CS Internally Limited 150°C −40°C ≤ TA ≤ 85°C LM2940IMP −65°C ≤ TJ ≤ +150°C Soldering Temperature (Note 3) TO-220 (T), Wave TO-263 (S) (Note 1) −55°C ≤ TJ ≤ 125°C LM2940J, LM2940WG −40°C ≤ TJ ≤ 125°C LM2940LD 260°C, 10s 235°C, 30s 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 5V Typ LM2940 Limit (Note 5) 8V LM2940/883 Limit (Note 6) Typ 6.25V ≤ VIN ≤ 26V Output Voltage Line Regulation 5 mA ≤ IO ≤ 1A 4.85/4.75 4.85/4.75 5.15/5.25 5.15/5.25 20 50 40/50 LM2940, LM2940/883 35 50/80 50/100 LM2940C 35 50 100 mADC and 20 mArms, 35 VO + 2V ≤ VIN ≤ 26V, 5.00 LM2940 Limit (Note 5) LM2940/883 Limit (Note 6) Units 9.4V ≤ VIN ≤ 26V 7.76/7.60 7.76/7.60 VMIN 8.24/8.40 8.24/8.40 VMAX 20 80 50/80 mVMAX 55 80/130 80/130 mVMAX 55 80 1000/1000 mΩ 8.00 IO = 5 mA Load Regulation Output Impedance 50 mA ≤ IO ≤ 1A 1000/1000 55 15/20 10 15/20 15/20 mAMAX 50/60 30 45/60 50/60 mAMAX 700/700 240 1000/1000 μVrms fO = 120 Hz Quiescent VO +2V ≤ VIN ≤ 26V, Current IO = 5 mA LM2940, LM2940/883 10 15/20 LM2940C 10 15 VIN = VO + 5V, 30 45/60 IO = 1A Output Noise 10 Hz − 100 kHz, Voltage IO = 5 mA Ripple Rejection fO = 120 Hz, 1 Vrms, 150 IO = 100 mA LM2940 72 60/54 66 54/48 LM2940C 72 60 66 54 fO = 1 kHz, 1 Vrms, 60/50 dBMIN 54/48 dBMIN IO = 5 mA Long Term Stability Dropout Voltage 20 32 mV/ 1000 Hr IO = 1A 0.5 0.8/1.0 0.7/1.0 0.5 0.8/1.0 0.7/1.0 VMAX IO = 100 mA 110 150/200 150/200 110 150/200 150/200 mVMAX 3 www.national.com LM2940/LM2940C SOT-223 (MP) LLP-8 (LD) ESD Susceptibility (Note 4) Absolute Maximum Ratings (Note 1) LM2940/LM2940C Output Voltage (VO) Parameter 5V Conditions Short Circuit Current (Note 7) Maximum Line RO = 100Ω Transient LM2940, T ≤ 100 ms 8V Typ LM2940 Limit (Note 5) LM2940/883 Limit (Note 6) Typ LM2940 Limit (Note 5) LM2940/883 Limit (Note 6) 1.9 1.6 1.5/1.3 1.9 1.6 1.6/1.3 75 60/60 75 60/60 LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms 40/40 55 45 Reverse Polarity RO = 100Ω DC Input Voltage LM2940, LM2940/883 −30 −15/−15 LM2940C −30 −15 −75 −50/−50 Reverse Polarity RO = 100Ω Transient Input LM2940, T ≤ 100 ms Voltage LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms −15/−15 40/40 55 45 −30 −15/−15 −30 −15 −75 −50/−50 −45/−45 −55 −15/−15 Units AMIN VMIN VMIN VMIN −45/−45 −45/−45 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 9V 10V LM2940 Limit (Note 5) Typ 10.5V ≤ VIN ≤ 26V Output Voltage 5 mA ≤ IO ≤1A 9.00 8.73/8.55 Typ VO + 2V ≤ VIN ≤ 26V, Units 11.5V ≤ VIN ≤ 26V 10.00 9.27/9.45 Line Regulation LM2940 Limit (Note 5) 9.70/9.50 VMIN 10.30/10.50 VMAX 20 90 20 100 mVMAX LM2940 60 90/150 65 100/165 mVMAX LM2940C 60 90 100 mADC and 20 mArms, 60 IO = 5 mA Load Regulation Output Impedance 50 mA ≤ IO ≤ 1A 65 mΩ fO = 120 Hz Quiescent VO +2V ≤ VIN < 26V, Current IO = 5 mA LM2940 10 15/20 LM2940C 10 15 VIN = VO + 5V, IO = 1A 30 45/60 Output Noise 10 Hz − 100 kHz, 270 Voltage IO = 5 mA Ripple Rejection fO = 120 Hz, 1 Vrms, 10 15/20 mAMAX 30 45/60 mAMAX μVrms 300 IO = 100 mA Long Term Stability www.national.com LM2940 64 52/46 LM2940C 64 52 34 63 36 4 51/45 dBMIN mV/ 1000 Hr Short Circuit 10V Typ LM2940 Limit (Note 5) Typ LM2940 Limit (Note 5) IO = 1A 0.5 0.8/1.0 0.5 0.8/1.0 VMAX IO = 100 mA 110 150/200 110 150/200 mVMAX (Note 7) 1.9 1.6 1.9 1.6 AMIN 75 60/60 VMIN −30 −15/−15 VMIN −75 −50/−50 VMIN Parameter Dropout Voltage 9V Conditions Units Current Maximum Line RO = 100Ω Transient T ≤ 100 ms LM2940 75 60/60 LM2940C 55 45 Reverse Polarity RO = 100Ω DC Input Voltage LM2940 −30 −15/−15 LM2940C −30 −15 Reverse Polarity RO = 100Ω Transient Input T ≤ 100 ms LM2940 −75 −50/−50 LM2940C −55 −45/−45 Voltage 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 12V 15V Typ LM2940 Limit (Note 5) 12.00 11.64/11.40 11.64/11.40 12.36/12.60 12.36/12.60 20 120 75/120 LM2940, LM2940/883 55 120/200 120/190 LM2940C 55 120 100 mADC and 20 mArms, 80 Conditions LM2940/833 Limit (Note 6) Typ 13.6V ≤ VIN ≤ 26V Output Voltage Line Regulation 5 mA ≤ IO ≤1A VO + 2V ≤ VIN ≤ 26V, LM2940 Limit (Note 5) LM2940/833 Limit (Note 6) Units 16.75V ≤ VIN ≤ 26V 15.00 20 14.55/14.25 14.55/14.25 VMIN 15.45/15.75 15.45/15.75 VMAX 150 95/150 mVMAX 150/240 mVMAX 1000/1000 mΩ 15/20 mAMAX 50/60 mAMAX 1000/1000 μVrms IO = 5 mA Load Regulation Output Impedance 50 mA ≤ IO ≤ 1A 70 1000/1000 150 100 fO = 120 Hz Quiescent Current VO +2V ≤ VIN ≤ 26V, IO = 5 mA LM2940, LM2940/883 10 15/20 LM2940C 10 15 45/60 VIN = VO + 5V, IO = 1A 30 Output Noise 10 Hz − 100 kHz, 360 Voltage IO = 5 mA 5 15/20 10 15 50/60 30 45/60 1000/1000 450 www.national.com LM2940/LM2940C Output Voltage (VO) LM2940/LM2940C Output Voltage (VO) Typ LM2940 Limit (Note 5) LM2940 66 54/48 LM2940C 66 54 Parameter Ripple Rejection 12V Conditions 15V LM2940/833 Limit (Note 6) Typ LM2940 Limit (Note 5) 64 52 LM2940/833 Limit (Note 6) Units fO = 120 Hz, 1 Vrms, IO = 100 mA fO = 1 kHz, 1 Vrms, 52/46 IO = 5 mA Long Term Stability Dropout Voltage dBMIN 48 48/42 dBMIN mV/ 1000 Hr 60 IO = 1A 0.5 0.8/1.0 0.7/1.0 0.5 0.8/1.0 0.7/1.0 VMAX IO = 100 mA 110 150/200 150/200 110 150/200 150/200 mVMAX 1.9 1.6 1.6/1.3 1.9 1.6 1.6/1.3 AMIN 75 60/60 40/40 VMIN −15/−15 VMIN −45/−45 VMIN Short Circuit Current (Note 7) Maximum Line RO = 100Ω Transient LM2940, T ≤ 100 ms LM2940/883, T ≤ 20 ms 40/40 LM2940C, T ≤ 1 ms 55 45 LM2940, LM2940/883 −30 −15/−15 LM2940C −30 −15 −75 −50/−50 −55 −45/−45 Reverse Polarity RO = 100Ω DC Input Voltage Reverse Polarity RO = 100Ω Transient Input LM2940, T ≤ 100 ms Voltage LM2940/883, T ≤ 20 ms LM2940C, T ≤ 1 ms 55 45 −30 −15 −55 −45/−45 −15/−15 −45/−45 Thermal Performance Thermal Resistance Junction-to-Case, θ(JC) Thermal Resistance Junction-to-Ambient, θ(JA) 3-Lead TO-220 4 3-Lead TO-263 4 3-Lead TO-220 (Note 2) 60 3-Lead TO-263 (Note 2) 80 SOT-223(Note 2) 174 8-Lead LLP (Note 2) 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 882214 882213 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 882220 882219 Ripple Rejection Low Voltage Behavior 882225 882221 Low Voltage Behavior Low Voltage Behavior 882227 882226 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 882222 882208 www.national.com 10 Maximum Power Dissipation (SOT-223) 882224 882223 Maximum Power Dissipation (TO-263) 882210 11 www.national.com LM2940/LM2940C Maximum Power Dissipation (TO-220) LM2940/LM2940C Equivalent Schematic Diagram 882201 www.national.com 12 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. 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: 882206 FIGURE 1. ESR Limits 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. 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 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) 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 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. 13 www.national.com LM2940/LM2940C 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: Application Information 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. www.national.com 882240 FIGURE 5. θ(JA) vs. Copper (2 ounce) Area for the SOT-223 Package 14 882241 FIGURE 6. Maximum Power Dissipation vs. TA for the SOT-223 Package 15 www.national.com 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. 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. 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