LM48413 Ultra Low EMI, Filterless, 1.2W Stereo Class D Audio Power Amplifier with E2S and National 3D Enhancement General Description Key Specifications The LM48413 is a single supply, high efficiency, 1.2W/channel, filterless switching audio amplifier. The LM48413 features National’s Enhanced Emissions Suppression (E2S) system - a unique patented ultra low EMI, spread spectrum, PWM architecture. It significantly reduces RF emission while preserving audio quality and efficiency. The E2S system improves battery life, reduces external component count, board area consumption, system cost and product design cycle time. The LM48413TL is available in a micro-SMD package, further saving space. The LM48413 is designed to meet the demands of mobile phones and other portable communication devices. Operating from a single 5V supply, the device is capable of delivering 1.2W/channel of continuous output power to a 8Ω load with less than 1% THD+N. Flexible power supply requirements allow operation from 2.4V to 5.5V. The wide band spread spectrum architecture of the LM48413 reduces EMI-radiated emissions due to the modulator frequency. The LM48413 features high efficiency compared with conventional Class AB amplifiers. The E2S system includes an advanced, patent-pending edge rate control (ERC) architecture that further reduce emissions by minimizing the high frequency components of the device output, while maintaining its high quality audio reproduction and high efficiency (η = 85% at VDD = 3.6V, PO = 500mW). The LM48413 also includes National’s 3D audio enhancement that improves stereo sound quality. In devices where the left and right speakers are in close proximity, 3D enhancement affects channel specialization, widening the perceived soundstage. Output short circuit protection prevents the device from being damaged during fault conditions. Superior click and pop suppression eliminates audible transients on power up/down and during shutdown. Shutdown control also provided to maximizes power savings. ■ Quiescent Power Supply Current at 3.6V supply ■ Power Output at VDD = 5V, RL = 8Ω, THD ≤ 1% ■ Shutdown current 4mA (typ) 1.2W (typ) 0.03μA (typ) ■ Efficiency at 3.6V, 100mW into 8Ω 80% (typ) ■ Efficiency at 3.6V, 500mW into 8Ω 85% (typ) ■ Efficiency at 5V, 1W into 8Ω 86% (typ) Features ■ E2S system reduces EMI preserving audio quality and ■ ■ ■ ■ ■ ■ ■ ■ efficiency Output Short Circuit Protection Stereo Class D operation No output filter required National 3D Enhancement Minimum external components Click and Pop suppression Micro-power shutdown Available in space-saving approximately 2mm x 2.2mm micro SMD package Applications ■ Mobile phones ■ PDAs ■ Laptops EMI Plot Using 6 inch Speaker Cables EMI Radiation vs Frequency VDD = 3V, RL = 15μH + 8Ω + 15μH 30063536 Boomer® is a registered trademark of National Semiconductor Corporation. © 2009 National Semiconductor Corporation 300635 www.national.com LM48413 Ultra Low EMI, Filterless, 1.2W Stereo Class D Audio Power Amplifier with E2S and National 3D Enhancement January 9, 2009 LM48413 Typical Application 30063541 FIGURE 1. Typical Audio Amplifier Application Circuit www.national.com 2 LM48413 Connection Diagrams 30063539 Top View XY = 2 Digit date code TT = Die Traceability G = Boomer Family L2 = LM48413TL 30063538 Top View Order Number LM48413TL See NS Package Number TLA18CBA Ordering Information Order Number Package Package DWG # Transport Media MSL Level Green Status LM48413TL 18 Bump micro SMD TLA18CBA 250 units on tape and reel 1 RoHS & no Sb/Br LM48413TLX 18 Bump micro SMD TLA18CBA 3000 units on tape and reel 1 RoHS & no Sb/Br 3 www.national.com LM48413 Bump Descriptions Bump Name A1 INL- Description Left Channel Inverting Input A3 3DEN A5 OUTLA 3D Enable Input Left Channel Non-Inverting Output A7 OUTLB Left Channel Inverting Output B2 INL+ Left Channel Non-Inverting Input B4 3DL- Left Channel inverting 3D connection. Connect to 3DR- through C3D- and R3D- B6 GND Ground C1 3DL+ Left Channel non-inverting 3D connection. Connect to 3DR+ through C3D+ and R3D+ C3 3DR+ Right Channel non-inverting 3D connection. Connect to 3DL+ through C3D+ and R3D+ C5 VDD C7 PGND Power Ground D2 INR+ Right Channel Non-inverting Input D4 3DR- Right Channel inverting 3D connection. Connect to 3DL- through C3D- and R3D- D6 PVDD Amplifier Power Supply E1 INR- Right Channel Inverting Input E3 SD E5 OUTRA Right Channel Non-inverting Output E7 OUTRB Right Channel Inverting Output www.national.com Power Supply. Connect to PVDD supplying same voltage. Connect to GND for disabling the device. Connect to VDD for normal operation. 4 If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (Note 1) Storage Temperature Input Voltage Power Dissipation (Note 3) ESD Rating (Note 4) ESD Rating (Note 5) 150°C θJA 47°C/W Operating Ratings 6.0V −65°C to +150°C –0.3V to VDD + 0.3V Internally Limited 2000V 200V (Notes 1, 2) Temperature Range TMIN ≤ TA ≤ TMAX Supply Voltage (VDD, PVDD) Electrical Characteristics VDD = PVDD = 3.6V (Notes 1, 2) RL = 8Ω (Note 8), f = 1kHz, unless otherwise specified. Limits apply for TA = 25°C. −40°C ≤ TA ≤ 85°C 2.4V ≤ VDD ≤ 5.5V The following specifications apply for LM48413 Symbol VOS Parameter Conditions Typical Limit (Note 6) (Note 7) Differential Output Offset Voltage VIN = 0, VDD = 2.4V to 5.0V IDD Quiescent Power Supply Current VIN = 0, No Load, VSD = VDD, VDD = 3.6V VDD = 5V 4.3 5.2 ISD Shutdown Current VSD = GND 0.03 VIH Logic Input High Voltage VIL Logic Input Low Voltage TWU Wake-Up Time 4 AV Gain 24 RIN Input Resistance 20 3 Units (Limits) mV 5.5 7 mA (max) mA (max) 1 μA (max) 1.4 V (min) 0.4 V (max) ms 23.5 24.5 dB (min) dB (max) kΩ THD ≤ 10%, f = 1kHz, 22kHz BW PO THD+N PSRR Output Power (Per Channel) Total Harmonic Distortion + Noise Power Supply Rejection Ratio VDD = 5V 1.5 VDD = 3.6V 720 VDD = 2.5V 320 mW VDD = 5V 1.2 W VDD = 3.6V 600 mW VDD = 2.5V 260 mW PO = 500mW/Ch, f = 1kHz, 22kHz BW 0.03 % PO = 300mW/Ch, f = 1kHz, 22kHz BW 0.03 % 91 90 dB dB 72 dB RL = 8Ω, VDD = 5V 86 % W 600 mW (min) THD ≤ 1%, f = 1kHz, 22kHz BW VRIPPLE = 200mVP-P Sine, Inputs AC GND, CIN = 1μF, input referred fRIPPLE = 217Hz fRIPPLE = 1kHz VRIPPLE = 1VP-P fRIPPLE = 217Hz CMRR Common Mode Rejection Ratio η Efficiency XTALK Crosstalk PO = 500mW/Ch, f = 1kHz 93 dB SNR Signal-to-Noise Ratio VDD = 5V, PO = 1W 88 dB εOS Output Noise Input referred, A-Weighted 5 μV PO = 1W/Ch, f = 1kHz, 5 www.national.com LM48413 Junction Temperature Thermal Resistance Absolute Maximum Ratings (Notes 1, 2) LM48413 Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or other conditions beyond those indicated in the Recommended Operating Conditions is not implied. The Recommended Operating Conditionsindicate conditions at which the device is functional and the device should not be operated beyond such conditions. All voltages are measured with respect to the ground pin, unless otherwise specified. Note 2: The Electrical Characteristics tables list guaranteed specifications under the listed Recommended Operating Conditions except as otherwise modified or specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and are not guaranteed. Note 3: The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, θJA, and the ambient temperature, TA. The maximum allowable power dissipation is PDMAX = (TJMAX - TA) / θJA or the number given in Absolute Maximum Ratings, whichever is lower. Note 4: Human body model, applicable std. JESD22-A114C. Note 5: Machine model, applicable std. JESD22-A115-A. The ESD Machine Model rating of device bump E3 = 150V. Note 6: Typical values represent most likely parametric norms at TA = +25°C, and at the Recommended Operation Conditions at the time of product characterization and are not guaranteed. Note 7: Datasheet min/max specification limits are guaranteed by test or statistical analysis. Note 8: RL is a resistive load in series with two inductors to simulate an actual speaker load. For RL = 8Ω, the load is 15µH + 8Ω +15µH. www.national.com 6 LM48413 Typical Performance Characteristics THD+N vs Output Power/Channel f = 1kHz, RL = 8Ω, 22kHz BW THD+N vs Frequency VDD = 2.5V, POUT = 100mW/Ch RL = 8Ω, 22kHz BW 30063543 30063517 THD+N vs Frequency VDD = 3.6V, POUT = 250mW/Ch RL = 8Ω, 22kHz BW THD+N vs Frequency VDD = 5V, POUT = 375mW/Ch RL = 8Ω, 22kHz BW 30063521 30063519 Efficiency vs Output Power RL = 8Ω, f = 1kHz Power Dissipation vs Total Output Power RL = 8Ω, f = 1kHz 30063544 30063533 7 www.national.com LM48413 Output Power/Channel vs Supply Voltage RL = 8Ω, f = 1kHz, 22kHz BW PSRR and CMRR vs Frequency VDD = 3.6V, RL = 8Ω 30063537 30063542 Crosstalk vs Frequency VDD = 3.6V, PO = 500mW, RL = 8Ω Supply Current vs Supply Voltage No Load 30063531 30063529 EMI Radiation vs Frequency VDD = 3V, RL = 8Ω, 3 inch cables EMI Radiation vs Frequency VDD = 3V, RL = 8Ω, 6 inch cables 30063535 www.national.com 30063536 8 LM48413 EMI Radiation vs Frequency VDD = 3V, RL = 8Ω, 12 inch cables 30063534 9 www.national.com LM48413 Application Information fiers. A differential amplifier amplifies the difference between the two input signals. Traditional audio power amplifiers have typically offered only single-ended inputs resulting in a 6dB reduction of SNR relative to differential inputs. The LM48413 also offers the possibility of DC input coupling which eliminates the input coupling capacitors. A major benefit of the fully differential amplifier is the improved common mode rejection ratio (CMRR) over single-ended input amplifiers. The increased CMRR of the differential amplifier reduces sensitivity to ground offset related noise injection, especially important in noisy systems. GENERAL AMPLIFIER FUNCTION The LM48413 stereo Class D audio power amplifier features a filterless modulation scheme that reduces external component count, conserving board space and reducing system cost. The outputs of the device transition from PVDD to GND with a 390kHz switching frequency. With no signal applied, the outputs switch with a 50% duty cycle, in phase, causing the two outputs to cancel. This cancellation results in no net voltage across the speaker, thus there is no current to the load in the idle state. When an input signal is applied, the duty cycle (pulse width) of the LM48413 output's change. For increasing output voltage, the duty cycle of one side of each output increases, while the duty cycle of the other side of each output decreases. For decreasing output voltages, the converse occurs. The difference between the two pulse widths yields the differential output voltage. POWER DISSIPATION AND EFFICIENCY The major benefit of a Class D amplifier is increased efficiency versus a Class AB. The efficiency of the LM48413 is attributed to the region of operation of the transistors in the output stage. The Class D output stage acts as current steering switches, consuming negligible amounts of power compared to a Class AB amplifier. Most of the power loss associated with the output stage is due to the IR loss of the MOSFET on-resistance, along with switching losses due to gate charge. SHUTDOWN FUNCTION The LM48413 features a low current shutdown mode. Set SD = GND to disable the amplifier and reduce supply current to 0.03μA. Switch SD between GND and VDD for minimum current consumption in shutdown. The LM48413 may be disabled with shutdown voltages in between GND and VDD, but the idle current will be greater than the typical value. The LM48413 shutdown input has an internal 300kΩ pull-down resistor. The purpose of this resistor is to eliminate any unwanted state changes when this pin is floating. To minimize shutdown current, it should be driven to GND or left floating. If it is not driven to GND, or floating, a small increase in shutdown supply current will be noticed. PROPER SELECTION OF EXTERNAL COMPONENTS Power Supply Bypassing/Filtering Proper power supply bypassing is important for low noise performance and high PSRR. Place the 1μF supply bypass capacitor as close to the device as possible. Traditionally, a pair of bypass capacitors with typical value 0.1μF and 10μF are applied to the supply rail for increasing stability. Nevertheless, these capacitors do not eliminate the need for bypassing of the LM48413 supply pins. Input Capacitor Selection Input capacitors may be required for some applications, or when the audio source is single-ended. Input capacitors block the DC component of the audio signal, eliminating any conflict between the DC component of the audio source and the bias voltage of the LM48413. The input capacitors create a highpass filter with the input resistance RIN. The -3dB point of the high-pass filter is found using Equation 1 below. SPREAD SPECTRUM The LM48413 outputs are modulated in spread spectrum scheme eliminating the need for output filters, ferrite beads or chokes. During its operation, the switching frequency varies randomly by 30% about a 390kHz center frequency, reducing the wideband spectral content and improving EMI emissions radiated by the speaker and associated cables and traces. A fixed frequency class D exhibits large amounts of spectral energy at multiples of the switching frequency. The spread spectrum architecture of the LM48413 spreads the same energy over a larger bandwidth. The cycle-to-cycle variation of the switching period does not affect the audio reproduction, efficiency, or PSRR. f = 1 / 2πRINCIN ENHANCED EMISSIONS SUPPRESSION SYSTEM (E2S) The LM48413 features National’s patented E2S system that further reduces EMI, while maintaining high quality audio reproduction and efficiency. The advanced edge rate control (ERC) embedded within the E2S system works simultaneously with the spread spectrum already activated. The LM48413 ERC greatly reduces the high frequency components of the output square waves by controlling the output rise and fall times, slowing the transitions to reduce RF emissions, while maximizing THD+N and efficiency performance. (1) National 3D Enhancement The LM48413 features National’s 3D enhancement effect that widens the perceived soundstage of a stereo audio signal. The 3D enhancement increases the apparent stereo channel separation, improving audio reproduction whenever the left and right speakers are too close to one another. An external RC network shown in Figure 1 is required to enable the 3D effect. Because the LM48413 is a fully differential amplifier, there are two separate RC networks, one for each stereo input pair (INL+ and INR+, and INL- and INR-). Set 3DEN high to enable the 3D effect. Set 3DEN low to disable the 3D effect. DIFFERENTIAL AMPLIFIER EXPLANATION As logic supplies continue to shrink, system designers are increasingly turning to differential analog signal handling to preserve signal to noise ratios with restricted voltage swings. The LM48413 features two fully differential speaker ampli- www.national.com (Hz) The input capacitors can also be used to remove low frequency content from the audio signal. When the LM48413 is using a single-ended source, power supply noise on the ground is seen as an input signal. Setting the high-pass filter point above the power supply noise frequencies, 217Hz in a GSM phone, for example, filters out the noise such that it is not amplified and heard on the output. Capacitors with a tolerance of 10% or better are recommended for impedance matching and improved CMRR and PSRR. 10 f3D(–3dB) = 1 / 2π(R3D)(C3D) (Hz) 6dB whenever the 3D effect is enabled. The Equation (2) holds for both differential and single-end configuration. The recommended tolerance of the resistor value and capacitor value of the two RC networks are 5% and 10% respectively. Tolerance out of this range may affect the 3D gain and low frequency cut-off point too much. The desired sound quality of the 3D effect may not be obtained consequently. SINGLE-ENDED AUDIO AMPLIFIER CONFIGURATION The LM48413 is compatible with single-ended sources. When configured for single-ended inputs, input capacitors must be used to block and DC component at the input of the device. Figure 2 shows the typical single-ended applications circuit. (2) Enabling the 3D effect increase the gain by a factor of (1 +40kΩ/R3D). Setting R3D to 40kΩ results in a gain increase of 30063525 FIGURE 2. Single-Ended Circuit Diagram 11 www.national.com LM48413 The 3D RC network acts as a high-pass filter. The amount of the 3D effect is set by the R3D resistor. Decreasing the value of R3D increases the 3D effect. The C3D capacitor sets the frequency at which the 3D effect occurs. Increasing the value of C3D decreases the low frequency cutoff point, extending the 3D effect over a wider bandwidth. The low frequency cutoff point is given by Equation 2: LM48413 AUDIO AMPLIFIER GAIN The LM48413 has a fix gain value 24dB which is suitable for ordinary audio applications. To reduce the amplifier gain, insert two pairs of external input resistors with same value before the IC’s input signal pins. Figure 3 show the configuration of these input resistors and the amplifier’s internal gain setting. Accordingly, the overall amplifier gain is given by Equation 3: AV = 2 * (160k) / (20k + RIN ) (3) For example, if the gain to be set is 12dB, then AV is equal to 4. Thus, Equation (3) the input resistors' value RIN = [(2 * 160k)/4] –20k = 60kΩ. 30063528 FIGURE 3. Audio Amplifier Gain Setting www.national.com 12 THD+N MEASUREMENT Class D amplifiers, by design, switch their output power devices at a much higher frequency than the accepted audio range (20Hz – 22kHz). Alternately switching the output voltage between VDD and GND allows the LM48413 to operate at much higher efficiency. However, it also increases the outof-band noise. Since THD+N measurement is a bandwidth limited measurement, it can be significantly affected by outof-band noise, resulting in a higher than expected THD+N measurement. To achieve a more accurate measurement of THD+N, the test equipment’s input bandwidth must be limited. The input filter limits the out-of-band noise resulting in a more relevant THD+N value. A low-pass filter with a cut-off at 28kHz was used in addition to the internal filter of the THD+N measurement equipment (See Figure 4). In real applications, the output filters are not necessary since the speakers will act as low-pass filters blocking the remaining switching noise and smoothing the output signals. Instead of connecting the LM48413's BTL outputs to speakers during measurements, the 28kHz low-pass filter is used as shown in Figure 4. This measurement technique also applies to measurements such as PSRR, CMRR, and output power. 30063540 FIGURE 4. THD+N Measurement Test Setup 13 www.national.com LM48413 or traces acting as antennas. The EMI output spectrums of LM48413 evaluation board connected with different speaker cable lengths to an 8Ω load were measured (See Typical Performance Characteristics). Lengths from 3 inches to 12 inches are shown all fall within the limit of the FCC Class B requirement. PCB LAYOUT GUIDELINES As output power increases, interconnect resistance (PCB traces and wires) between the amplifier, load and power supply create a voltage drop. The voltage loss due to the traces between the LM48413 and the load results in lower output power and decreased efficiency. Higher trace resistance between the supply and the LM48413 has the same effect as a poorly regulated supply, increasing ripple on the supply line, and reducing peak output power. The effects of residual trace resistance increases as output current increases due to higher output power, decreased load impedance or both. To maintain the highest output voltage swing and corresponding peak output power, the PCB traces that connect the output pins to the load and the supply pins to the power supply should be as wide as possible to minimize trace resistance. The use of power and ground planes will give the best THD +N performance. In addition to reducing trace resistance, the use of power planes creates parasitic capacitors that help to filter the power supply line. The inductive nature of the transducer load can also result in overshoot on one or both edges, clamped by the parasitic diodes to GND and VDD in each case. From an EMI standpoint, this is an aggressive waveform that can radiate or conduct to other components in the system and cause interference. It is essential to keep the power and output traces short and well shielded if possible. Use of ground planes beads and micros-strip layout techniques are all useful in preventing unwanted interference. As the distance from the LM48413 and the speaker increases, the amount of EMI radiation increases due to the output wires LM48413 Bill Of Materials TABLE 1. LM48413 Demonstration Board Bill of Materials Item Designator Description 1 U1 Stereo Class-D 2 R1, R2 Resistor (0603) Part Number Qty LM48413TL 1 Value Recommended Supplier National Semiconductor 2 4.7kΩ ± 5% Towa GRM188R71C105KA01D 4 1µF ± 10%, 25V Murata 3 Ceramic Capacitor C1, C2, C3, C8 (0603) X7R 4 C4, C5, C6, C7 Ceramic Capacitor (1206) X7R C3216X741H105K 4 1µF ± 10%, 25V TDK 5 C9 Tantium Capacitor (1210) 594D106X0025B2T 1 10µF ± 10%, 25V Vishay 100kΩ Copal Electronics 6 JP5, JP6, JP7 Header 2-pin 3 7 JP1, JP2 Header 3-pin 2 8 JP3, JP4 Header 4-pin 2 9 R3, R4 Potentiometer www.national.com ST-4EB100k 14 2 LM48413 Demonstration Board Schematic 30063510 FIGURE 5. LM48413 Demonstration Board Schematic 15 www.national.com LM48413 Demonstration Board Layout 30063511 Top Silkscreen 30063515 Top Layer www.national.com 16 LM48413 30063513 Middle Layer 1 30063514 Middle Layer 2 17 www.national.com LM48413 30063512 Bottom Layer www.national.com 18 LM48413 Revision Table Rev Date 1.0 11/19/08 Initial release. Description 1.01 01/08/09 Text edits. 19 www.national.com LM48413 Physical Dimensions inches (millimeters) unless otherwise noted MicroSMD 18 Bump Package Order Number LM48413TL, LM48413TLX NS Package Number TLA18CBA X1 = 2.047mm ±0.030mm X2 = 2.250mm ±0.030mm X3 = 0.60mm ±0.075mm www.national.com 20 LM48413 Notes 21 www.national.com LM48413 Ultra Low EMI, Filterless, 1.2W Stereo Class D Audio Power Amplifier with E2S and National 3D Enhancement Notes For more National Semiconductor product information and proven design tools, visit the following Web sites at: 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 Reference www.national.com/vref Design Made Easy www.national.com/easy PowerWise® Solutions www.national.com/powerwise Solutions www.national.com/solutions Serial Digital Interface (SDI) www.national.com/sdi Mil/Aero www.national.com/milaero Temperature Sensors www.national.com/tempsensors Solar Magic® www.national.com/solarmagic Wireless (PLL/VCO) www.national.com/wireless Analog University® www.national.com/AU 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© 2009 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] German Tel: +49 (0) 180 5010 771 English Tel: +44 (0) 870 850 4288 National Semiconductor Asia Pacific Technical Support Center Email: [email protected] National Semiconductor Japan Technical Support Center Email: [email protected]