LM4510 Synchronous Step-Up DC/DC Converter with True Shutdown Isolation General Description Features The LM4510 is a current mode step-up DC/DC converter with a 1.2A internal NMOS switch designed to deliver up to 120 mA at 16V from a Li-Ion battery. The device's synchronous switching operation (no external Schottky diode) at heavy-load, and non-synchronous switching operation at light-load, maximizes power efficiency. True shutdown function by synchronous FET and related circuitry ensures input and output isolation. A programmable soft-start circuit allows the user to limit the amount of inrush current during startup. The output voltage can be adjusted by external resistors. The LM4510 features advanced short-circuit protection to maximize safety during output to ground short condition. During shutdown the feedback resistors and the load are disconnected from the input to prevent leakage current paths to ground. The LM4510 is available in a 10-pin thermally enhanced Leadless Leadframe Package: LLP-10. 18V@80 mA from 3.2V input 5V@280 mA from 3.2V input No external Schottky diode required 85% peak efficiency Soft start True shutdown isolation Stable with small ceramic or tantalum output capacitors Output short-circuit protection Feedback fault protection Input under-voltage lock out Thermal shutdown 0.002 A shutdown current Wide input voltage range: 2.7V to 5.5V 1.0 MHz fixed frequency operation Low-profile 10-pin LLP package (3mm x 3mm x 0.8mm) Applications Organic LED Panel Power Supply Charging Holster White LED Backlight USB Power Supply Class D Audio Amplifier Camera Flash LED Driver Typical Application Circuit 30031001 FIGURE 1. Typical Application Circuit (c) 2010 National Semiconductor Corporation 300310 www.national.com LM4510 Synchronous Step-Up DC/DC Converter with True Shutdown Isolation January 30, 2010 LM4510 Efficiency at VOUT = 16V 30031030 Connection Diagram LLP-10 No Pullback Package, 3mm x 3mm x 0.8mm NS Package Number SDA10A 30031002 Ordering Information Order Number SPEC Package Type NSC Package Drawing Package Marking LM4510SD NOPB LLP-10 SDA10A L4510 1000 Units, Tape and Reel LM4510SDX NOPB LLP-10 SDA10A L4510 4500 Units, Tape and Reel www.national.com 2 Supplied As LM4510 Pin Descriptions/Functions Pin Name 1 SW Function 2 PGND 3 VIN Analog and Power supply input. Input range: 2.7V to 5.5V. 4 EN Enable logic input. HIGH= Enabled, LOW=Shutdown. 5 SS Soft-start pin 6 AGND Analog ground 7 COMP Compensation network connection. Switch pin. Drain connections of both internal NMOS and PMOS devices. Power ground 8 FB Output voltage feedback connection. 9 N/C No internal connection. 10 VOUT DAP DAP Internal PMOS source connection for synchronous rectification. Die Attach Pad thermal connection 3 www.national.com LM4510 Absolute Maximum Ratings (Note 1, Note Operating Conditions Supply Voltage Range (VIN) Junction Temperature Range (TJ) (Note 6) Output Voltage Range (VOUT) 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN VOUT SW (Note 3) EN, SS, COMP FB PGND to AGND Continuous Power Dissipation (Note 4) Junction Temperature (TJ-MAX) Storage Temperature Range (TS) Lead Temperature (Soldering, 10 sec) (Note 5) ESD Ratings (Note 12) Human Body Model Machine Model -0.3V to 6.5V -0.3V to 21V -0.3V to VOUT+0.3V -0.3V to 6.5V -0.2V to 0.2V 2.7V to 5.5V -40C to +125C Up to 18V Thermal Properties Junction to Ambient Thermal Resistance (JA) LLP-10 Package (Note 7) 36C/W Internally Limited 150C -65C to +150C Electrical Characteristics 260C 2.0kV 200V (Note 8, Note 9) Limits in standard type face are for TJ = 25C only. Limits in boldface type apply over the full operating junction temperature range ( -40C TJ +125C). Unless otherwise stated the following conditions apply: VIN = 3.6V, EN = 3.6V. Symbol Parameter Conditions VFB FB Pin Voltage 2.7V VIN 5.5V IFB FB Pin Bias Current (Note 11) RDS(on) ICL Min (Note 8) Typ (Note 9) Max (Note 8) Units 1.24 1.265 1.29 V 0.050 1.5 A NMOS Switch RDS(on) ISW = 0.3A 0.45 1.1 PMOS Switch RDS(on) ISW = 0.3A, VOUT = 10V 0.9 1.1 1.2 1.8 A Device Switching EN = 3.6V, FB = COMP 1.7 2.5 mA Non-switching Current EN = 3.6V, FB > 1.29V 0.8 2.0 mA Shutdown Current EN = 0V 0.002 0.050 A IL SW Leakage Current (Note 11) SW = 20V 0.01 0.150 A IVOUT VOUT Bias Current (Note 11) VOUT = 20V 90 150 A IVL PMOS Switch Leakage Current 0.001 0.100 A fSW Switching Frequency 0.85 1.0 1.2 MHz DMAX Maximum Duty Cycle 88 94 DMIN Minimum Duty Cycle Gm Error Amplifier Transconductance IQ 1.0 NMOS Switch Current Limit 50 SW = 0V, VOUT = 20V FB = 0V % 15 20 % 70 130 200 mho 1.2 0.81 EN Threshold Device Enable HIGH Device Shutdown LOW 0.78 0.4 IEN EN Pin Bias Current 0 < EN < 3.6V 3.2 8.0 A FB Fault Protection Feedback Fault Protection V www.national.com ON Threshold 18.0 19.7 20.7 OFF Threshold 17.0 18.7 20.0 4 V Parameter UVLO Input Undervoltage Lockout ISS Soft-Start Pin Current (Note 10) Conditions Min (Note 8) Typ (Note 9) Max (Note 8) 2.5 2.65 2.1 2.35 9 11.3 ON Threshold OFF Threshold 15 Units V A Note 1: Absolute maximum ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions for which the device is intended to be functional, but device parameter specifications may not be guaranteed. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: All voltages are with respect to the potential at the GND pin. Note 3: This condition applies if VIN < VOUT. If VIN > VOUT, a voltage greater than VIN + 0.3V should not be applied to the VOUT or VSW pins. The absolute maximum specification applies to DC voltage. An extended negative voltage limit of -1V applies for a pulse of up to 1 s, and -2V for a pulse of up to 40 ns. An extended positive voltage limit of 22V applies for a pulse of up to 20 ns. Note 4: Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at TJ=150C (Typ.) and disengages at TJ=140C (Typ.). Note 5: For detailed soldering information and specifications, please refer to National Semiconductor Application Note 1187: Leadless Leadframe Package (LLP) , available at www.national.com. Note 6: In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may have to be derated. Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-OP = 125C), the maximum power dissipation of the device in the application (PD-MAX), and the junction-to ambient thermal resistance of the part/package in the application (JA), as given by the following equation: TA-MAX = TJ-MAX-OP - (JA x PD-MAX) Note 7: Junction-to-ambient thermal resistance (JA) is taken by a numerical analysis conforming to JEDEC standards. In applications where high maximum power dissipation exists (high VIN, high IOUT), special care must be paid to thermal dissipation issues when designing the board layout. For more information on these topics, please refer to Application Note 1187: Leadless Leadframe Package (LLP). Note 8: All limits guaranteed at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are production tested, guaranteed through statistical analysis or guaranteed by design. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL). Note 9: Typical numbers are at 25C and represent the most likely norm. Note 10: Current flows out of the pin. Note 11: Current flows into the pin. Note 12: The Human body model is a 100 pF capacitor discharged through a 1.5 k resistor into each pin (MIL-STD-883 3015.7). The machine model is a 200 pF capacitor discharged directly into each pin. 5 www.national.com LM4510 Symbol LM4510 Typical Performance Characteristics LM4510SD, Circuit of Figure 1, (L=4.7 H, COILCRAFT, DO3316-472ML; CIN=4.7 F, TDK, C2012X5R0J475K; COUT=10 F, AVX, 12103D106KAT2A; CS=10 nF, TDK, C1608C0G1E103J; CC1=2.2 nF, Taiyo Yuden, TMK107SD222JA-T; RC=46.4 K, Yageo, 9t06031A4642FBHFT), VIN=3.6V, VOUT=16V, TA=25C, unless otherwise noted. Switching Quiescent Current vs VIN RDS(on) vs Temperature at VIN= 3.6V 30031035 30031005 Load Capabilty vs VIN (VOUT = 16 V ) Output Voltage vs Temperature (VOUT = 17 V ) 30031006 www.national.com 30031010 6 LM4510 Switching Frequency vs Temperature Load Regulation (VOUT = 16 V ) 30031011 30031012 Load Regulation (VOUT = 5 V ) Line Regulation (VOUT = 16 V ) 30031034 30031029 Line Regulation (VOUT = 5 V ) Efficiency vs Output Current (VOUT = 16 V ) 30031030 30031033 7 www.national.com LM4510 Efficiency vs Output Current (VOUT = 12 V ) Efficiency vs Output Current (VOUT = 5 V, L= DO3314-472ML) 30031031 30031032 Line Transient Response (VOUT = 16 V ) Load Transient Response (VOUT = 16 V ) 30031003 30031004 Start Up (VOUT = 16 V, RLOAD = 530 ) Shut Down (VOUT = 16 V, RLOAD = 940 ) 30031009 30031007 www.national.com 8 LM4510 Short Circuit Response (VOUT = 16 V) Output Voltage Ripple (VOUT = 16 V, IOUT = 90 mA) 30031098 30031008 Output Voltage Ripple (VOUT = 5 V, IOUT = 100 mA) 30031099 9 www.national.com LM4510 Block Diagram 30031013 FIGURE 2. LM4510 Block Diagram OPERATION IN SYNCHRONOUS CONTINUOUS CONDUCTION MODE (CYCLE 1, CYCLE 2) Operation Description LM4510 is a peak current-mode, fixed-frequency PWM boost regulator that employs both Synchronous and Non-Synchronous Switching. The DC/DC regulator regulates the feedback output voltage providing excellent line and load transient response. The operation of the LM4510 can best be understood by referring to the Block Diagram. NON-SYNCHRONOUS OPERATION The device operates in Non-synchronous Mode at light load (IOUT < 10 mA) or when output voltage is lower than 10V (typ.). At light load, LM4510 automatically changes its switching operation from 'Synchronous' to 'Non-Synchronous' depending on VIN and L. Non-Synchronous operation at light load maximizes power efficiency by reducing PMOS driving loss. www.national.com 30031014 FIGURE 3. Schematic of Synchronous Boost Converter 10 The LM4510 turns on when EN is high. There is an internal pull-down resistor on the EN pin so the device is in a normally off state. SHORT CIRCUIT PROTECTION When VOUT goes down to VIN-0.7V (typ.), the device stops switching due to the short-circuit protection circuitry and the short-circuit output current is limited to IINIT_CHARGE. Cycle 1 Description Refer to Figure 4. NMOS switch turn-on Inductor current increases and flows to GND. PMOS switch turn-off Isolate VOUT from SW Output capacitor supplies load current. FEEDBACK FAULT PROTECTION The LM4510 features unique Feedback Fault Protection to maximize safety when the feedback resistor is not properly connected to a circuit or the feedback node is shorted directly to ground. Feedback fault triggers VOUT monitoring. During monitoring, if VOUT reaches a protection level, the device shuts down. When the feedback network is reconnected and VOUT is lower than the OFF threshold level of Feedback Fault Protection, VOUT monitoring stops. VOUT is then regulated by the control loop. INPUT UNDER-VOLTAGE LOCK-OUT The LM4510 has dedicated circuitry to protect the IC and the external components when the battery voltage is lower than the preset threshold. This under-voltage lock-out with hysteresis prevents malfunctions during startup or abnormal power off. 30031015 FIGURE 4. Equivalent Circuit During Cycle 1 During operation, EAMP output voltage (VCOMP) increases for larger loads and decreases for smaller loads. When the sum of the ramp compensation and the sensed NMOS current reaches a level determined by the EAMP output voltage, the PWM COMP resets the logic, turning off the NMOS power device and turning on the PMOS power device. THERMAL SHUTDOWN If the die temperature exceeds 150C (typ.), the thermal protection circuitry shuts down the device. The switches remain off until the die temperature is reduced to approximately 140C (typ.). Cycle 2 Description Refer to Figure 5. NMOS Switch turn-off PMOS Switch turnon Inductor current decreases and flows through PMOS Inductor current recharges output capacitor and supplies load current. Application Information ADJUSTING OUTPUT VOLTAGE The output voltage is set using the feedback pin and a resistor voltage divider (RF1, RF2) connected to the output as shown in the Typical Application Circuit. The ratio of the feedback resistors sets the output voltage. RF2 Selection First of all choose a value for RF2 generally between 10 k and 25 k. 30031016 RF1 Selection Calculate RF1 using the following equation: FIGURE 5. Equivalent Circuit During Cycle 2 After the switching period the oscillator then sets the driver logic again repeating the process. ON/OFF CONTROL The LM4510 shuts down when the EN pin is low. In this mode the feedback resistors and the load are disconnected from the input in order to avoid leakage current flow and to allow the output voltage to drop to 0V. Table 1 gives suggested component values for several typical output voltages. TABLE 1. Suggested Component Values for Different Output Voltages Output Voltage (V) RF2 (k) RF1 (k) RC (k) CC1 (nF) 16 20.5 240 46.4 2.2 12 20.5 174 46.4 2.2 5 20.5 60.4 46.4 2.2 3.3 20.5 33 46.4 2.2 11 www.national.com LM4510 Synchronous boost converter is shown in Figure 3. At the start of each cycle, the oscillator sets the driver logic and turns on the NMOS power device and turns off the PMOS power device. LM4510 MAXIMUM OUTPUT CURRENT When the output voltage is set at different level, it is important to know the maximum load capability. By first order estimation, IOUT(MAX) can be estimated by the following equation: I Define The inductor ripple current is given by the following equations: Where D is the on-duty cycle of the switching regulator. A common choice is to set IL to about 30% of IL_AVE. INDUCTOR SELECTION The larger value inductor makes lower peak inductor current and reduces stress on internal power NMOS. On the other hand, the smaller value inductor has smaller outline, lower DCR and a higher current capacity. Generally a 4.7 H to 15 H inductor is recommended. IL_PK ICL Check & IMIN Define The peak inductor current is given by the following equation: IL_AVE CHECK The average inductor current is given by the following equation: To prevent loss of regulation, ensure that the NMOS power switch current limit is greater than the worst-case peak inductor current in the target application. Also make sure that the inductor saturation current is greater than the peak inductor current under the worst-case load transient, high ambient temperature and startup conditions. Refer to Table 2 for suggested inductors. Where IOUT is output current, is the converter efficiency of the total driven load and D' is the off duty cycle of the switching regulator. Inductor DC current rating (40C temperature rise) should be more than the average inductor current at worst case. TABLE 2. Suggested Inductors and Their Suppliers Model Vendor Dimensions LxWxH (mm) D.C.R (max) DO3314-472ML COILCRAFT 3.3mm x 3.3mm x 1.4mm 320 m DO3316P-472ML COILCRAFT 12.95mm x 9.4mm x 5.4mm 18 m improved line support and transient response, tantalum capacitors can be used. INPUT CAPACITOR SELECTION Due to the presence of an inductor, the input current waveform is continuous and triangular. So the input capacitor is less critical than output capacitor in boost applications. Typically, a 4.7 F to 10 F ceramic input capacitor is recommended on the VIN pin of the IC. ICOUT_RMS Check The RMS current in the output capacitor is given by the following equation: ICIN_RMS Check The RMS current in the input capacitor is given by the following equation: The output capacitor should be capable of handling the RMS current. The ESR and ESL of the output capacitor directly control the output ripple. Use capacitors with low ESR and ESL at the output for high efficiency and low ripple voltage. The output capacitor also affects the soft-start time. See Soft-Start Function and Soft-Start Capacitor Selection. Table 3 shows suggested input and output capacitors. The input capacitor should be capable of handling the RMS current. OUTPUT CAPACITOR SELECTION The output capacitor in a boost converter provides all the output current when the switch is closed and the inductor is charging. As a result, it sees very large ripple currents. A ceramic capacitor of value 4.7 F to 10 F is recommended at the output. If larger amounts of capacitance are desired for www.national.com 12 Model Type Vendor Voltage Rating Case Size Inch (mm) 4.7 F for CIN C2012X5R0J475 Ceramic, X5R TDK 6.3V 0805 (2012) GRM21BR60J475 Ceramic, X5R muRata 6.3V 0805 (2012) JMK212BJ475 Ceramic, X5R Taiyo-Yuden 6.3V 0805 (2012) C2012X5R0J475K Ceramic, X5R TDK 6.3V 0603 (1608) TMK316BJ106KL Ceramic, X5R Taiyo-Yuden 25V 1206 (3216) 12103D106KAT2A Ceramic, X5R AVX 25V 1210 (3225) 10 F for COUT CS Selection The soft-start time without load can be estimated as: SOFT-START FUNCTION AND SOFT-START CAPACITOR SELECTION The LM4510 has a soft-start pin that can be used to limit the input inrush current. Connect a capacitor from SS pin to GND to set the soft-start period. Figure 6 describes the soft start process. * Initial charging period: When the device is turned on, the control circuitry linearly regulating initial charge current charges VOUT by limiting the inrush current. * Soft-start period: After VOUT reaches VIN -0.7V (typ.), the device starts switching and the CS is charged at a constant current of 11 A, ramping up to VIN. This period ends when VSS reaches VFB. CS should be large enough to ensure soft-start period ends after CO is fully charged. During the initial charging period, the required load current must be smaller than the initial charge current to ensure VOUT reaches VIN -0.7V (typ.). Where the IINIT_CHARGE is Initial Charging Current depending on VIN and ISS_CHARGE (11 A (typ.)). Also, when selecting the fuse current rating, make sure the value is higher than the initial charging current. COMPENSATION COMPONENT SELECTION The LM4510 provides a compensation pin COMP to customize the voltage loop feedback. It is recommended that a series combination of RC and CC1 be used for the compensation network, as shown in the typical application circuit. In addition, CC2 is used for compensating high frequency zeros. The series combination of RC and CC1 introduces a pole-zero pair according to the following equations: In addition, CC2 introduces a pole according to the following equation: Where RO is the output impedance of the error amplifier, approximately 1 M, and amplifier voltage gain is typically 200 V/V depending on temperature and VIN. Refer to Table 4 for suggested soft start capacitor and compensation components. 30031023 FIGURE 6. Soft Start Timing Diagram TABLE 4. Suggested CS and Compensation Components Model Type Vendor Voltage Rating Case Size Inch (mm) (CS) C1608C0G1E103J Ceramic, X5R TDK 6.3V 603 (1608) (C1)TMK107SD222JA-T Ceramic, X5R Taiyo Yuden 25V 603 (1608) (RC) 9t06031A4642FBHFT Resistor Yageo Corporation 1/10W 603 (1608) 13 www.national.com LM4510 TABLE 3. Suggested CIN and COUT Capacitors and Their Suppliers LM4510 connections for the COUT capacitor can increase the series resistance, which directly affects output voltage ripple and makes noise during output voltage sensing. 3. All voltage-sensing resistors (RF1, RF2) should be kept close to the FB pin to minimize copper trace connections that can inject noise into the system. The ground connection for the voltage-sensing resistor should be connected directly to the AGND pin. 4. Trace connections made to the inductor should be minimized to reduce power dissipation, EMI radiation and increase overall efficiency. Also poor trace connection increases the ripple of SW. 5. CS, CC1, CC2, RC must be placed close to the device and connected to AGND. 6. The AGND pin should connect directly to the ground. Not connecting the AGND pin directly, as close to the chip as possible, may affect the performance of the LM4510 and limit its current driving capability. AGND and PGND should be separate planes and should be connected at a single point. 7. For better thermal performance, DAP should be connected to ground, but cannot be used as the primary ground connection. The PC board land may be modified to a "dog bone" shape to reduce LLP thermal impedance. For detail information, refer to Application Note AN-1187. LAYOUT CONSIDERATIONS AND THERMAL MANAGEMENT 30031096 FIGURE 7. Evaluation Board Layout FLASH/TORCH APPLICATION LM4510 can be configured to drive white LEDs for the flash and torch functions. The flash/torch can be set up with the circuit shown in Figure 8 by using the resistor RT to determine the current in Torch Mode and RF to determine the current in Flash Mode. The amount of current can be estimated using the following equations: High frequency switching regulators require very careful layout of components in order to get stable operation and low noise. All components must be as close as possible to the LM4510 device. Refer to Figure 7 as an example. Some additional guidelines to be observed: 1. CIN must be placed close to the device and connected directly from VIN to PGND pins. This reduces copper trace resistance, which affects the input voltage ripple of the device. For additional input voltage filtering, typically a 0.1 uF bypass capacitor can be placed between VIN and AGND. This bypass capacitor should be placed near the device closer than CIN. 2. COUT must also be placed close to the device and connected directly from VOUT to PGND pins. Any copper trace 30031028 FIGURE 8. Flash/Torch Circuit Using LM4510 www.national.com 14 LM4510 Physical Dimensions inches (millimeters) unless otherwise noted 10-pin LLP Package For Ordering, Refer to Ordering Information Table NS Package Number SDA10A 3mm x 3mm x 0.8mm 15 www.national.com LM4510 Synchronous Step-Up DC/DC Converter with True Shutdown Isolation Notes For more National Semiconductor product information and proven design tools, visit the following Web sites at: www.national.com Products Design Support Amplifiers www.national.com/amplifiers WEBENCH(R) Tools www.national.com/webench Audio www.national.com/audio App Notes www.national.com/appnotes Clock and Timing www.national.com/timing Reference Designs www.national.com/refdesigns Data Converters www.national.com/adc Samples www.national.com/samples Interface www.national.com/interface Eval Boards www.national.com/evalboards LVDS www.national.com/lvds Packaging www.national.com/packaging Power Management www.national.com/power Green Compliance www.national.com/quality/green Switching Regulators www.national.com/switchers Distributors www.national.com/contacts LDOs www.national.com/ldo Quality and Reliability www.national.com/quality LED Lighting www.national.com/led Feedback/Support www.national.com/feedback Voltage References www.national.com/vref Design Made Easy www.national.com/easy www.national.com/powerwise Applications & Markets www.national.com/solutions Mil/Aero www.national.com/milaero PowerWise(R) Solutions Serial Digital Interface (SDI) www.national.com/sdi Temperature Sensors www.national.com/tempsensors SolarMagicTM www.national.com/solarmagic PLL/VCO www.national.com/wireless www.national.com/training PowerWise(R) Design University 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. EXCEPT AS PROVIDED IN NATIONAL'S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. LIFE SUPPORT POLICY NATIONAL'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness. National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. Copyright(c) 2010 National Semiconductor Corporation For the most current product information visit us at www.national.com National Semiconductor Americas Technical Support Center Email: support@nsc.com Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Technical Support Center Email: europe.support@nsc.com National Semiconductor Asia Pacific Technical Support Center Email: ap.support@nsc.com National Semiconductor Japan Technical Support Center Email: jpn.feedback@nsc.com