LM3414/LM3414HV 1A 60W* Common Anode Capable Constant Current Buck LED Driver Requires No External Current Sensing Resistor General Description Features The LM3414 and LM3414HV are 1A 60W* common anode capable constant current buck LED drivers. They are exceptionally suitable to drive single string of 3W HBLED with up to 96% efficiency. They accept input voltages from 4.5VDC to 65VDC and deliver up to 1A average LED current with ±3% accuracy. The integrated low-side N-channel power MOSFET and current sensing element realize simple and low component count circuitry as no bootstrapping capacitor and external current sensing resistor are required. An external smallsignal resistor to ground provides very fine LED current adjustment, analog dimming as well as thermal fold-back functions. Constant switching frequency operation eases EMI. No external loop compensation network is needed. The proprietary Pulse-Level-Modulation (PLM) control method benefits in high conversion efficiency and true average LED current regulation. Fast response time realizes fine LED current pulse fulfilling the 240 Hz 256-step dimming resolution requirement for general lighting. The LM3414 and LM3414HV are available in ePSOP-8 and 3mm x 3mm LLP-8 packages. ■ ■ ■ ■ ■ *Thermal de-rating applies according to actual operation conditions ■ ■ ■ ■ ■ ■ ■ Support LED power up to 60W*: 18x 3W HBLEDs Requires NO external current sensing resistor ±3% LED current accuracy Up to 96% efficiency High contrast ratio (Minimum dimming current pulse width <10 µS) Integrated low-side N-channel MOSFET Adjustable Constant LED current from 350mA to 1000mA Support analog dimming and thermal fold-back Wide input voltage range: 4.5V to 42V (LM3414) 4.5V to 65V (LM3414HV) Constant Switching Frequency adjustable from 250 kHz to 1000 kHz Thermal shutdown protection Power enhanced ePSOP-8 or 3mm x 3mm LLP-8 package Appications ■ ■ ■ ■ High Power LED Driver Architectural Lighting, Office Troffer Automotive Lighting MR-16 LED Lamp Simplified Application Schematic 30124801 © 2010 National Semiconductor Corporation 301248 www.national.com LM3414/LM3414HV 1A 60W* Common Anode Capable Constant Current Buck LED Driver Requires No External Current Sensing Resistor August 9, 2010 LM3414/LM3414HV Connection Diagram 30124803 Ordering Information Order Number Package Type NSC Package Drawing LM3414MR ePSOP-8 MRA08A LM3414MRX Supplied As 95 Units in Anti-Static Rails 2,500 Units on Tape and Reel LM3414HVMR 95 Units in Anti-Static Rails LM3414HVMRX 2500 Units on Tape and Reel LM3414SD LLP-8 SDA08AG 1,000 Units on Tape and Reel LM3414SDX 4,500 Units on Tape and Reel LM3414HVSD 1,000 Units on Tape and Reel LM3414HVSDX 4,500 Units on Tape and Reel www.national.com 2 Pin(s) Name 1 VCC Description Application Information Internal Regulator Output Pin This pin should be bypassed to ground by a ceramic capacitor with a minimum value of 1µF. 2 PGND Power Ground Pin Ground for power circuitry. Reference point for all stated voltages. Must be externally connected to EP and GND. 3 IADJ Average Output Current Adjustment Pin Connect resistor RIADJ from this pin to ground to adjust the average output current. 4 GND Analog Ground Pin Analog ground connection for internal circuitry, must be connected to PGND external to the package. 5 FS Switching Frequency Setting Pin Connect resistor RFS from this pin to ground to set the switching frequency. 6 DIM PWM Dimming Control Pin Apply logic level PWM signal to this pin controls the intend brightness of the LED string. 7 LX Drain of N-MOSFET Switch Connect this pin to the output inductor and anode of the schottky diode. 8 VIN Input Voltage Pin The input voltage should be in the range of 4.5V to 42V (LM3414) or 4.5V to 65V (LM3414HV). EP EP Thermal Pad (Power Ground) Used to dissipate heat from the package during operation. Must be electrically connected to PGND external to the package. 3 www.national.com LM3414/LM3414HV Pin Descriptions LM3414/LM3414HV Storage Temp. Range Soldering Information Lead Temp. (Soldering 10s) Infrared/Convection Reflow (20sec) Absolute Maximum Ratings (LM3414) (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND VIN to GND (Transient) LX to PGND LX to PGND (Transient) FS, IADJ to GND DIM to GND ESD Rating Human Body Model (Note 2) www.national.com -65°C to 125°C 260°C 235°C Operating Ratings (LM3414) -0.3V to 42V 45V (500 ms) -0.3V to 42V -3V(2 ns) to 45V (500 ms) -0.3V to 5V -0.3V to 6V VIN Junction Temperature Range 2kV 4 4.5V to 42V −40°C to +125°C Thermal Resistance θJA (ePSOP-8 Package) 45°C/W Thermal Resistance θJA (LLP-8 Package) 54°C/W If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND VIN to GND (Transient) LX to PGND LX to PGND (Transient) FS, IADJ to GND DIM to GND ESD Rating Human Body Mode (Note 2) -65°C to 125°C 260°C 235°C Operating Ratings (LM3414HV) -0.3V to 65V 67V (500 ms) -0.3V to 65V -3V(2 ns) to 67V (500 ms) -0.3V to 5V -0.3V to 6V VIN Junction Temperature Range 4.5V to 65V −40°C to +125°C Thermal Resistance θJA (ePSOP-8 Package) 45°C/W Thermal Resistance θJA (LLP-8 Package) 54°C/W 2kV 5 www.national.com LM3414/LM3414HV Storage Temp. Range Soldering Information Lead Temp. (Soldering 10s) Infrared/Convection Reflow (20sec) Absolute Maximum Ratings (LM3414HV) (Note 1) LM3414/LM3414HV Electrical Characteristics VIN = 24V unless otherwise indicated. Typical and limits appearing in plain type apply for TA=TJ= +25°C (Note 4). Limits appearing in boldface type apply over full Operating Temperature Range. Datasheet min/max specification limits are obtained under device test mode and guaranteed by design, test, or statistical analysis. LM3414 Symbol Parameter Conditions Min Typ Max Units SYSTEM PARAMETERS IIN-DIM-HIGH Operating Current 4.5V ≤ Vin ≤ 42V RIADJ = 3.125 kΩ VDIM = High 2.2 3.2 3.5 mA IIN-DIM-LOW Standby Current 4.5V ≤ Vin ≤ 42V RIADJ = 3.125 kΩ VDIM = Low 0.8 1.15 1.4 mA ILX-OFF LX Pin Current Main Switch Turned OFF VLX = VIN = 42V Parameter Conditions Min Typ Max Units 6 µA LM3414HV Symbol SYSTEM PARAMETERS IIN-DIM-HIGH Operating Current 4.5V ≤ Vin ≤ 65V RIADJ = 3.125 kΩ VDIM = High 2.2 3.3 3.6 mA IIN-DIM-LOW Standby Current 4.5V ≤ Vin ≤ 65V RIADJ = 3.125 kΩ VDIM = Low 0.8 1.2 1.45 mA ILX-OFF LX Pin Current Main Switch Turned OFF VLX = VIN= 65V 6.5 µA LM3414/LM3414HV Symbol Parameter Conditions Min Typ Max Units RIADJ = 3.125 kΩ TA = 25°C 0.97 1 1.03 A RIADJ = 3.125 kΩ TA = –40°C to 125°C 0.95 1 1.05 A VCC Decreasing 3.60 3.75 3.90 V 1.230 1.255 1.280 1.0 1.2 SYSTEM PARAMETERS ILED Average LED Current VCC-UVLO Vcc UVLO Threshold VCC-UVLO-HYS Vcc UVLO Hysteresis VIADJ IADJ Pin voltage VDIM DIM Pin Threshold VDIM-HYS DIM Pin Hysteresis fSW Switching Frequency Range fSW-TOL Switching Frequency Tolerance tON-MIN Minimum On-time 300 VDIM Increasing mV 100 RFS = 40 kΩ V V mV 250 500 1000 kHz 420 500 580 kHz 400 ns 6.0 V INTERNAL VOLTAGE REGULATOR VCC VCC Regulator Output Voltage (Note CVCC = 1µF, No Load to IVCC = 2mA 5) Vin = 4.5V, 2 mA Load 4.7 5.4 3.8 4.2 V MAIN SWITCH RLX Resistance Across LX and GND Main Switch Turned ON 1.8 Ω THERMAL PROTECTION TSD www.national.com Thermal Shutdown Temperature TJ Rising 6 170 °C Parameter Conditions Min Typ Max Units TSD-HYS Thermal Shutdown Temperature Hysteresis TJ Falling 10 °C Junction to Ambient, ePSOP-8 package 45 °C/W 0 LFPM Air Flow (Note 3) LLP-8 package 54 °C/W THERMAL RESISTANCE θJA Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device is intended to be functional. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: The human body model is a 100pF capacitor discharged through a 1.5 kΩ resistor into each pin. Note 3: Tested on a 4 layer JEDEC board. Four vias provided under the exposed pad. See JESD51-5 and JESD51-7. The value of the θJA for the LLP package is specifically dependent on the 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. Note 4: Typical specification represent the most likely parametric norm at 25°C operation. Note 5: VCC provides self bias for the internal gate drive and control circuits. Device thermal limitations limit external loading to the pin. 7 www.national.com LM3414/LM3414HV Symbol LM3414/LM3414HV Typical Performance Characteristics All curves taken at VIN = 48V with configuration in typical application for driving twelve power LEDs with ILED = 1A shown in this datasheet. TA = 25°C, unless otherwise specified. IOUT vs VIN, (4 - 8 LED) LM3414HV IOUT vs VIN, (10 - 18 LED) LM3414HV 30124843 30124844 Efficiency vs VIN, (4 - 8 LED) LM3414HV Efficiency vs VIN, (10 - 18 LED) LM3414HV 30124859 30124860 IOUT vs Temperature (TA) (6 LED, VIN = 24V), LM3414HV IOUT vs Temperature (TA) (12 LED, VIN = 48V), LM3414HV 30124841 www.national.com 30124842 8 LM3414/LM3414HV VCC vs Temperature (TA) LM3414HV VIADJ vs Temperature (TA) LM3414HV 30124839 30124840 IOUT and VLX LM3414HV ILX and VDIM LM3414HV 30124816 30124817 LED Current with PWM Dimming (VDIM Rising) LM3414HV LED Current with PWM Dimming (VDIM Falling) LM3414HV 30124856 30124857 9 www.national.com LM3414/LM3414HV LED Current with PWM Dimming (9µs dimming pulse), LM3414HV 30124858 www.national.com 10 LM3414/LM3414HV Block Diagram 30124820 Operation Description Application Information OVERVIEW The LM3414/14HV is a high power floating buck LED driver with wide input voltage ranges. It requires no external current sensing elements and loop compensation networks. The integrated power N-MOSFET enables high output power with up to 1000 mA output current. The combination of Pulse Width Modulation (PWM) control architecture and the proprietary Pulse Level Modulation (PLM) guarantees accurate current regulation, good EMI performance and provides high flexibility on inductor selection. High speed dimming control input allows precision and high resolution brightness control for applications require fine brightness adjustment. SETTING THE SWITCHING FREQUENCY Both the LM3414 and LM3414HV are PWM LED drivers that contain a clock generator to generate constant switching frequency for the device. The switching frequency is determined by the resistance of an external resistor RFS in the range of 250 kHz to 1 MHz. Lower resistance of RFS results in higher switching frequency. The switching frequency of the LM3414/14HV is governed by the following equation: 11 www.national.com LM3414/LM3414HV 30124845 30124822 FIGURE 1. Switching Frequency vs RFS FIGURE 2. LED Current vs RIADJ fSW (kHz) RFS (kΩ) IOUT (mA) RIADJ (kΩ) 250 80 350 8.93 500 40 500 6.25 1000 20 700 4.46 1000 3.13 TABLE 1. Examples for fSW Settings TABLE 2. Examples for IOUT Settings To ensure accurate current regulation, the LM3414/14HV should be operated in continuous conduction mode (CCM) and the on time should not be shorter than 400 ns under all operation condition. The LED current can be set to any level in the range from 350 mA to 1A. In order to provide accurate LED current, RIADJ should be a resistor with no more than 0.5% tolerance. If the IADJ pin is accidentally shorted to GND (RIADJ = 0), the output current will be limited to avoid damaging the circuit. When the over current protection is activated, current regulation cannot be maintained until the over-current condition is cleared. SETTING LED CURRENT The LM3414/14HV requires no external current sensing resistor for LED current regulation. The average output current of the LM3414/14HV is adjustable by varying the resistance of the resistor, RIADJ that connects across the IADJ and GND pins. The IADJ pin is internally biased to 1.255V. The LED current is then governed by the following equation: MINIMUM SWITCH ON-TIME As the LM3414 features a 400 ns minimum ON time, it is essential to make sure the ON time of the internal switch is not shorter than 400 ns when setting the LED driving current. If the switching ON time is shorter than 400 ns, the accuracy of the LED current may not maintain and exceed the rated current of the LEDs. The ratio of the LED forward voltage to input voltage is restricted by the following restriction: where 350 mA < ILED < 1A PEAK SWITCH CURRENT LIMIT The LM3414/14HV features an integrated switch current limiting mechanism that protects the LEDs from being overdriven. The switch current limiter will be triggered when the switch current is three times exceeding the current level set by RIADJ. Once the current limiter is triggered, the internal power switch turns OFF for 3.6 µs to allow the inductor to discharge and cycles repetitively until the over current condition is removed. The current limiting feature is exceptionally important to avoid permanent damage of the LM3414/14HV application circuit due to short circuit of LED string. www.national.com 12 LM3414/LM3414HV 30124823 FIGURE 3. Waveforms of a Floating Buck LED Driver with PLM INDUCTOR SELECTION To ensure proper output current regulation, the LM3414/14HV must operate in Continuous Conduction Mode (CCM). With the incorporation of PLM, the peak-to-peak inductor current ripple can be set as high as ±60% of the defined average output current. The minimum inductance of the inductor is decided by the defined average LED current and allowable inductor current ripple. The minimum inductance can be found by the equations shown in below: Since: INTERNAL VCC REGULATOR The LM3414/14HV features a 5.4V internal voltage regulator that connects between the VIN and VCC pins for powering internal circuitry and provide biases to external components. The VCC pin must be bypassed to the GND pin with a 1µF ceramic capacitor, CVCC that connected to the pins as close as possible. When the input voltage falls below 6V, the VCC voltage will drop below 5.4V and decrease proportionally as Vin decreases. The device will shutdown as the VCC voltage falls below 3.9V. When the internal regulator is used to provide bias to external circuitry, it is essential to ensure the current sinks from VCC pin does not exceed 2mA to maintain correct voltage regulation. CONTROL SCHEME The main control circuitry of the LM3414/14HV is generally a Pulse-Width-Modulated (PWM) controller with the incorporation of the Pulse-Level-Modulation (PLM) technology. PLM is a technology that facilitates true output average current control without the need to sense the output current directly. In the LM3414/LM3414HV, the PLM circuit senses the current of the internal switch through an integrated current sensing circuitry to realize average output current control. The use of PLM reduces the power losses on current sensor as it needs current information only when the switch is turned ON. In general, the LED drivers with current sensing resistor at the output, the power dissipation on the current sensing resistor is ILED2 x RISNS, where ILED is the average output current and RISNS is the resistance of the current sensing resistor. In the LM3414/LM3414HV, because of the incorporation of PLM, power dissipates on the RISNS only in ON period of the internal power switch. The power loss on RISNS becomes ILED2 x RISNS x D, where D is the switching duty cycle. For example, when the switching duty cycle, D of a converter is 0.5, the power loss on RISNS with PLM is half of those with conventional output current sensing. Thus: The LM3414/14HV can maintain LED current regulation without output filter capacitor. This is because the inductor of the floating buck structure provides continuous current to the LED throughout the entire switching cycle. When LEDs are driven without filter capacitor, the LED peak current must not set exceeding the rated current of the LED. The peak LED current is governed by the following equation: INTERNAL N_MOS POWER SWITCH The LM3414/14HV features an integrated N-channel power MOSFET that connects between the LX and GND pins for power switching. With the switch turned ON, the resistance across the LX and GND pins is 1.8Ω maximum. 13 www.national.com LM3414/LM3414HV PULSE-LEVEL-MODULATION (PLM) OPERATION PRINCIPLES The Pulse-Level-Modulation is a patented method to ensure accurate average output current regulation without the need of direct output current sensing. Figure 3 shows the current waveforms of a typical buck converter under steady state, where, IL1 is the inductor current and ILX is the main switch current flowing into the LX pin. For a buck converter operating in steady state, the mid-point of the RAMP section of the main switch current is equal to the average level of the inductor current hence the average output current. In short, by regulating the mid-point of the RAMP section of the main switch current with respect to a precise reference level, PLM achieves output current regulation by sensing the main switch current solely. PWM DIMMING CONTROL The DIM pin of the LM3414/14HV is an input with internal pullup that accepts logic signals for average LED current control. Applying a logic high (above 1.2V) signal to the DIM pin or leaving the DIM pin open will enable the device. Applying a logic low signal (below 0.9V) to the DIM pin will disable the switching activity of the device but maintain VCC regulator active. The LM3414/14HV allows the inductor current to slew up to the preset regulated level at full speed instead of charging the inductor with multiple restrained switching duty cycles. This enables the LM3414/14HV to achieve high speed dimming and very fine dimming control as shown in Figure 4 and Figure 5: 30124824 FIGURE 4. LED Current Slews up with Multiple Switching Cycle www.national.com 14 LM3414/LM3414HV 30124825 FIGURE 5. Shortened Current Slew up Time of the LM3414/14HV To ensure normal operation of the LM3414/14HV, it is recommended to set the dimming frequency not higher than 1/10 of the switching frequency. The minimum dimming duty cycle is limited by the 400 ns minimum ON time. In applications that require high dimming contrast ratio, low dimming frequency should be used. 15 www.national.com LM3414/LM3414HV can be increased or decreased by applying external bias current to the IADJ pin. The simplified circuit diagram for facilitating analog dimming is as shown in figure 6. ANALOG DIMMING CONTROL The IADJ pin can be used as an analog dimming signal input. As the average output current of the LM3414 depends on the current being drawn from the IADJ pin, thus the LED current 30124826 FIGURE 6. Analog LED Current Control Circuit When external bias current IEXT is applied to the IADJ pin, the reduction of LED current follows the equations: ILED decreases linearly as IEXT increases. This feature is exceptionally useful for the applications with analog dimming control signals such as those from analog temperature sensors and ambient light sensors. Provided that www.national.com 16 LM3414/LM3414HV DESIGN EXAMPLE Figure 7 shows an example circuit for analog dimming control using simple external biasing circuitry with a variable resistor. 30124827 FIGURE 7. Example Analog Dimming Control Circuit In the figure, the variable resistor VR1 controls the base voltage of Q1 and eventually adjusts the bias voltage of current to the IADJ pin (IEXT). As the resistance of VR1 increases and the voltage across VR1 exceeds 1.255V + 0.7V, the LED current starts to decrease as IEXT increases. where The analog dimming begins only when IEXT > 0. DESIGN CONSIDERATIONS The overall performance of the LED driver is highly depends on the PCB layout and component selection. To minimize connection losses and parasitic inductance of the traces, the best practice is to keep the copper traces connecting the inductor, power switch and rectifier short and thick . Long traces on critical power paths will introduce voltage and current spikes to the LM3414/LM3414HV. If the voltage spike level exceeds the absolute maximum pin voltage of the LM3414, it could damage the device and LEDs. To avoid physical damage of the circuit, a Transient Voltage Suppressor (TVS) can be added across VIN and GND pins to suppress the spike voltage. This also helps in absorbing the input voltage spike when the circuit is powered through physical switch upon power up. 17 www.national.com LM3414/LM3414HV Additional Application Circuit 30124828 FIGURE 8. LM3414/14HV Design Example (IOUT = 500 mA) Bill of Materials Designation Description Package Manufacture Part # Vendor U1 LED Driver IC LM3414 / LM3414HV ePSOP-8 LM3414 / LM3414HV NSC L1 Inductor 47 µH 8 x 8 x 4.9 (mm) MMD-08EZ-470M-SI Mag.Layers D1 Schottky Diode 100V 2.0A SMP SS2PH10-M3 Vishay CIN Cap MLCC 100V 2.2 µF X7R 1210 GRM32ER72A225KA35L Murata CVCC Cap MLCC 16V 1.0 µF X5R 603 GRM39X5R105K16D52K Murata RIADJ Chip Resistor 3.24 kΩ 1% 603 CRCW06033241F Vishay RFS Chip Resistor 40.2 kΩ 1% 603 CRCW06034022F Vishay 30124829 FIGURE 9. Application Circuit of LM3414/14HV with Temperature Fold-Back Circuitry and PWM Dimming www.national.com 18 LM3414/LM3414HV Physical Dimensions inches (millimeters) unless otherwise noted 8-Lead LLP Package NS Package Number SDA08A 8-Lead ePSOP Package NS Package Number MRA08B 19 www.national.com LM3414/LM3414HV 1A 60W* Common Anode Capable Constant Current Buck LED Driver Requires No External Current Sensing Resistor 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® 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® Solutions Serial Digital Interface (SDI) www.national.com/sdi Temperature Sensors www.national.com/tempsensors SolarMagic™ www.national.com/solarmagic PLL/VCO www.national.com/wireless www.national.com/training PowerWise® 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© 2010 National Semiconductor Corporation For the most current product information visit us at www.national.com National Semiconductor Americas Technical Support Center Email: [email protected] Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Technical Support Center Email: [email protected] National Semiconductor Asia Pacific Technical Support Center Email: [email protected] National Semiconductor Japan Technical Support Center Email: [email protected]