LM4809 LM4809 Dual 105mW Headphone Amplifier with Active-Low Shutdown Mode Literature Number: SNAS126E LM4809 Dual 105mW Headphone Amplifier with Active-Low Shutdown Mode General Description Key Specifications The LM4809 is a dual audio power amplifier capable of delivering 105mW per channel of continuous average power into a 16 load with 0.1% (THD+N) from a 5V power supply. n THD+N at 1kHz at 105mW continuous average power into 16 0.1% (typ) n THD+N at 1kHz at 70mW continuous average power into 32 0.1% (typ) n Shutdown Current 0.4A (typ) Boomer audio power amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. Since the LM4809 does not require bootstrap capacitors or snubber networks, it is optimally suited for low-power portable systems. The unity-gain stable LM4809 can be configured by external gain-setting resistors. The LM4809 features an externally controlled, active-low, micropower consumption shutdown mode, as well as an internal thermal shutdown protection mechanism. Features n n n n n n Active-low shutdown mode "Click and Pop" reduction circuitry Low shutdown current LLP, MSOP, and SO surface mount packaging No bootstrap capacitors required Unity-gain stable Applications n n n n Headphone Amplifier Personal Computers Microphone Preamplifier PDA's Typical Application 20009001 *Refer to the Application Information Section for information concerning proper selection of the input and output coupling capacitors. FIGURE 1. Typical Audio Amplifier Application Circuit Boomer (R) is a registered trademark of National Semiconductor Corporation. (c) 2004 National Semiconductor Corporation DS200090 www.national.com LM4809 Dual 105mW Headphone Amplifier with Active-Low Shutdown Mode April 2004 LM4809 Connection Diagrams MSOP Package MSOP Marking 20009066 20009002 Top View Order Number LM4809MM See NS Package Number MUA08A SO Package SO Marking 20009067 20009002 Top View Order Number LM4809MA See NS Package Number M08A LLP Package (LD) LLP (LD) Marking 20009068 20009061 Top View Order Number LM4809LD See NS Package Number LDA08B LLP Package (LQ) LLP (LQ) Marking 20009070 20009069 Top View Order Number LM4809LQ See NS Package Number LQB08A www.national.com 2 Thermal Resistance If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. JC (SO) Supply Voltage JA (SO) 6.0V Storage Temperature 170C/W 35C/W JA (MSOP) 210C/W JC (MSOP) 56C/W -65C to +150C JA (LLP) 117C/W (Note 9) 3.5kV JA (LLP) 150C/W (Note 10) 250V JC (LLP) 15C/W ESD Susceptibility (Note 4) ESD Machine model (Note 8) Junction Temperature (TJ) 150C Soldering Information (Note 1) Operating Ratings Small Outline Package Vapor Phase (60 sec.) 215C Infrared (15 sec.) 220C Temperature Range TMIN TA TMAX -40C T A 85C 2.0V VCC 5.5V Supply Voltage (VCC) Note 1: See AN-450 "Surface Mounting and their Effects on Product Reliability" for other methods of soldering surface mount devices. Electrical Characteristics VDD = 5V (Notes 2, 3) The following specifications apply for VDD = 5V unless otherwise specified, limits apply to TA = 25C. Symbol Parameter Conditions LM4809 Typ (Note 5) Supply Voltage VDD IDD Supply Current VIN = 0V, IO = 0A 1.4 Units (Limits) Limit (Note 7) 2.0 V (min) 5.5 V (max) 3 mA (max) ISD Shutdown Current VIN = 0V, VSHUTDOWN = GND 0.4 2 A(max) VOS Output Offset Voltage VIN = 0V 4.0 50 mV(max) PO Output Power THD+N = 0.1%, f = 1kHz 65 mW (min) RL = 16 105 RL = 32 70 mW THD+N Total Harmonic Distortion PO = 50mW, RL = 32 f = 20Hz to 20kHz 0.3 % Crosstalk Channel Separation RL = 32; PO = 70mW 70 dB PSRR Power Supply Rejection Ratio CB = 1.0F; VRIPPLE = 200mVPP, f = 1kHz; Input terminated into 50 70 dB VSDIH Shutdown Voltage Input High 0.8 x VDD V (min) VSDIL Shutdown Voltage Input Low 0.2 x VDD V (max) Electrical Characteristics VDD = 3.3V (Notes 2, 3) The following specifications apply for VDD = 3.3V unless otherwise specified, limits apply to TA = 25C. Symbol Parameter Conditions LM4809 Typ (Note 5) Limit (Note 7) Units (Limits) IDD Supply Current VIN = 0V, IO = 0A 1.1 ISD Shutdown Current VIN = 0V, VSHUTDOWN = GND 0.4 mA A VOS Output Offset Voltage VIN = 0V 4.0 mV PO Output Power THD+N = 0.1%, f = 1kHz RL = 16 40 mW RL = 32 28 mW THD+N Total Harmonic Distortion PO = 25mW, RL = 32 f = 20Hz to 20kHz 0.4 % Crosstalk Channel Separation RL = 32; PO = 25mW 70 dB 3 www.national.com LM4809 Absolute Maximum Ratings (Note 2) LM4809 Electrical Characteristics VDD = 3.3V (Notes 2, 3) (Continued) The following specifications apply for VDD = 3.3V unless otherwise specified, limits apply to TA = 25C. Symbol Parameter Conditions LM4809 Typ (Note 5) CB = 1.0F; VRIPPLE = 200mVPP, f = 1kHz; Input terminated into 50 Limit (Note 7) Units (Limits) 70 dB PSRR Power Supply Rejection Ratio VSDIH Shutdown Voltage Input High 0.8 x VDD V (min) VSDIL Shutdown Voltage Input Low 0.2 x VDD V (max) Electrical Characteristics VDD = 2.6V (Notes 2, 3) The following specifications apply for VDD = 2.6V unless otherwise specified, limits apply to TA = 25C. Symbol Parameter Conditions LM4809 Typ (Note 5) IDD Supply Current VIN = 0V, IO = 0A 0.9 Limit (Note 7) Units (Limits) mA ISD Shutdown Current VIN = 0V, VSHUTDOWN = GND 0.2 A VOS Output Offset Voltage VIN = 0V 4.0 mV PO Output Power THD+N = 0.1%, f = 1kHz RL = 16 20 mW RL = 32 16 mW THD+N Total Harmonic Distortion PO = 15mW, RL = 32 f = 20Hz to 20kHz 0.6 % Crosstalk Channel Separation RL = 32; PO = 15mW 70 dB PSRR Power Supply Rejection Ratio CB = 1.0F; VRIPPLE = 200mVPP, f = 1kHz; Input terminated into 50 70 dB VSDIH Shutdown Voltage Input High 0.8 x VDD V (min) VSDIL Shutdown Voltage Input Low 0.2 x VDD V (max) Note 2: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Note 3: All voltages are measured with respect to the ground pin, unless otherwise specified. Note 4: Human body model, 100pF discharged through a 1.5k resistor. Note 5: Typical specifications are specified at +25OC and represent the most likely parametric norm. Note 6: Tested limits are guaranteed to National's AOQL (Average Outgoing Quality Level). Note 7: Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis. Note 8: Machine Model ESD test is covered by specification EIAJ IC-121-1981. A 200pF cap is charged to the specified voltage, then discharged directly into the IC with no external series resistor (resistance of discharge path must be under 50Ohms). Note 9: The given JA is for an LM4809 packaged in an LDA08B wit the Exposed-Dap soldered to a printed circuit board copper pad with an area equivalent to that of the Exposed-Dap itself. Note 10: The given JA is for an LM4809 packaged in an LDA08B with the Exposed-Dap not soldered to any printed circuit board copper. External Components Description Components (Figure 1) Functional Description 1. Ri The inverting input resistance, along with Rf, set the closed-loop gain. Ri, along with Ci, form a high pass filter with fc = 1/(2RiCi). 2. Ci The input coupling capacitor blocks DC voltage at the amplifier's input terminals. Ci, along with Ri, create a highpass filter with fC = 1/(2RiCi). Refer to the section, Selecting Proper External Components, for an explanation of determining the value of Ci. 3. Rf The feedback resistance, along with Ri, set closed-loop gain. 4. CS This is the supply bypass capacitor. It provides power supply filtering. Refer to the Application Information section for proper placement and selection of the supply bypass capacitor. 5. CB This is the BYPASS pin capacitor. It provides half-supply filtering. Refer to the section, Selecting Proper External Components, for information concerning proper placement and selection of CB. 6. CO This is the output coupling capacitor. It blocks the DC voltage at the amplifier's output and forms a high pass filter with RL at fO = 1/(2RLCO) www.national.com 4 LM4809 Typical Performance Characteristics THD+N vs Frequency THD+N vs Frequency 20009003 20009004 THD+N vs Frequency THD+N vs Frequency 20009005 20009006 THD+N vs Frequency THD+N vs Frequency 20009007 20009008 5 www.national.com LM4809 Typical Performance Characteristics (Continued) THD+N vs Frequency THD+N vs Frequency 20009009 20009010 THD+N vs Frequency THD+N vs Frequency 20009011 20009012 THD+N vs Output Power THD+N vs Output Power 20009013 www.national.com 20009014 6 LM4809 Typical Performance Characteristics (Continued) THD+N vs Output Power THD+N vs Output Power 20009015 20009016 THD+N vs Output Power THD+N vs Output Power 20009017 20009018 THD+N vs Output Power THD+N vs Output Power 20009019 20009020 7 www.national.com LM4809 Typical Performance Characteristics (Continued) Output Power vs Load Resistance THD+N vs Output Power 20009022 20009021 Output Power vs Load Resistance Output Power vs Load Resistance 20009023 20009024 Output Power vs Supply Voltage Output Power vs Power Supply 20009025 www.national.com 20009026 8 LM4809 Typical Performance Characteristics (Continued) Output Power vs Power Supply Dropout Voltage vs Supply Voltage 20009028 20009027 Power Dissipation vs Output Power Power Dissipation vs Output Power 20009029 20009030 Power Dissipation vs Output Power Channel Separation 20009031 20009033 9 www.national.com LM4809 Typical Performance Characteristics (Continued) Noise Floor Power Supply Rejection Ratio 20009034 20009035 Open Loop Frequency Response Open Loop Frequency Response 20009051 20009050 Open Loop Frequency Response Supply Current vs Supply Voltage 20009038 20009044 www.national.com 10 MICRO-POWER SHUTDOWN The voltage applied to the SHUTDOWN pin controls the LM4809's shutdown function. Activate micro-power shutdown by applying a logic low voltage to the SHUTDOWN pin. The logic threshold is typically VDD/2. When active, the LM4809's micro-power shutdown feature turns off the amplifier's bias circuitry, reducing the supply current. The low 0.4A typical shutdown current is achieved by applying a voltage that is as near as GND as possible to the SHUTDOWN pin. A voltage that is above GND may increase the shutdown current. PDMAX = (TJMAX - TA) / JA For package MUA08A, JA = 210C/W. TJMAX = 150C for the LM4809. Depending on the ambient temperature, TA, of the system surroundings, Equation 2 can be used to find the maximum internal power dissipation supported by the IC packaging. If the result of Equation 1 is greater than that of Equation 2, then either the supply voltage must be decreased, the load impedance increased or TA reduced. For the typical application of a 5V power supply, with a 32 load, the maximum ambient temperature possible without violating the maximum junction temperature is approximately 133.2C provided that device operation is around the maximum power dissipation point. Power dissipation is a function of output power and thus, if typical operation is not around the maximum power dissipation point, the ambient temperature may be increased accordingly. Refer to the Typical Performance Characteristics curves for power dissipation information for lower output powers. There are a few ways to control the micro-power shutdown. These include using a single-pole, single-throw switch, a microprocessor, or a microcontroller. When using a switch, connect an external 100k pull-down resistor between the SHUTDOWN pin and GND. Connect the switch between the SHUTDOWN pin and VDD. Select normal amplifier operation by closing the switch. Opening the switch connects the SHUTDOWN pin to GND through the pull-down resistor, activating micro-power shutdown. The switch and resistor guarantee that the SHUTDOWN pin will not float. This prevents unwanted state changes. In a system with a microprocessor or a microcontroller, use a digital output to apply the control voltage to the SHUTDOWN pin. Driving the SHUTDOWN pin with active circuitry eliminates the pull-down resistor. EXPOSED-DAP PACKAGE PCB MOUNTING CONSIDERATION The LM4809's exposed-Dap (die attach paddle) package (LD or LQ) provides a low thermal resistance between the die and the PCB to which the part is mounted and soldered. This allows rapid heat transfer from the die to the surrounding PCB copper traces, ground plane, and surrounding air. The LD or LQ package should have its DAP soldered to a copper pad on the PCB. The DAP's PCB copper pad may be connected to a large plane of continuous unbroken copper. This plane forms a thermal mass, heat sink, and radiation area. However, since the LM4809 is designed for headphone applications, connecting a copper plane to the DAP's PCB copper pad is not required. The LM4809's Power Dissipation vs Output Power Curve in the Typical Performance Characteristics shows that the maximum power dissipated is just 45mW per amplifier with a 5V power supply and a 32 load. Further detailed and specific information concerning PCB layout, fabrication, and mounting an LD or LQ package is available from National Semiconductor's Package Engineering Group under application note AN1187. POWER SUPPLY BYPASSING As with any power amplifier, proper supply bypassing is critical for low noise performance and high power supply rejection. Applications that employ a 5V regulator typically use a 10F in parallel with a 0.1F filter capacitors to stabilize the regulator's output, reduce noise on the supply line, and improve the supply's transient response. However, their presence does not eliminate the need for a local 1.0F tantalum bypass capacitance connected between the LM4809's supply pins and ground. Keep the length of leads and traces that connect capacitors between the LM4809's power supply pin and ground as short as possible. Connecting a 4.7F capacitor, CB, between the BYPASS pin and ground improves the internal bias voltage's stability and improves the amplifier's PSRR. The PSRR improvements increase as the bypass pin capacitor value increases. Too large, however, increases the amplifier's turn-on time. The selection of bypass capacitor values, especially CB, depends on desired PSRR requirements, click and pop performance (as explained in the section, Selecting Proper External Components), system cost, and size constraints. SELECTING PROPER EXTERNAL COMPONENTS Optimizing the LM4809's performance requires properly selecting external components. Though the LM4809 operates well when using external components with wide tolerances, best performance is achieved by optimizing component values. The LM4809 is unity-gain stable, giving a designer maximum design flexibility. The gain should be set to no more than a given application requires. This allows the amplifier to achieve minimum THD+N and maximum signal-to-noise ratio. These parameters are compromised as the closed-loop gain increases. However, low gain demands input signals with greater voltage swings to achieve maximum output power. Fortunately, many signal sources such as audio POWER DISSIPATION Power dissipation is a major concern when using any power amplifier and must be thoroughly understood to ensure a successful design. Equation 1 states the maximum power dissipation point for a single-ended amplifier operating at a given supply voltage and driving a specified output load. PDMAX = (VDD) 2 / (22RL) (2) (1) Since the LM4809 has two operational amplifiers in one package, the maximum internal power dissipation point is twice that of the number which results from Equation 1. Even 11 www.national.com LM4809 with the large internal power dissipation, the LM4809 does not require heat sinking over a large range of ambient temperature. From Equation 1, assuming a 5V power supply and a 32 load, the maximum power dissipation point is 40mW per amplifier. Thus the maximum package dissipation point is 80mW. The maximum power dissipation point obtained must not be greater than the power dissipation that results from Equation 2: Application Information LM4809 Application Information the BYPASS pin is stable, the device becomes fully operational. During device turn-on, a transient (pop) is created from a voltage difference between the input and output of the amplifier as the voltage on the BYPASS pin reaches 1/2 VDD. For this discussion, the input of the amplifier refers to the node between RI and CI. Ideally, the input and output track the voltage applied to the BYPASS pin. During turn-on, the buffer-configured amplifier output charges the input capacitor, CI, through the input resistor, RI. This input resistor delays the charging time of CI thereby causing the voltage difference between the input and output that results in a transient (pop). Higher value capacitors need more time to reach a quiescent DC voltage (usually 1/2 VDD) when charged with a fixed current. Decreasing the value of CI and RI will minimize turn-on pops at the expense of the desired -3dB frequency. (Continued) CODECs have outputs of 1VRMS (2.83VP-P). Please refer to the Audio Power Amplifier Design section for more information on selecting the proper gain. Input and Output Capacitor Value Selection Amplifying the lowest audio frequencies requires high value input and output coupling capacitors (CI and CO in Figure 1). A high value capacitor can be expensive and may compromise space efficiency in portable designs. In many cases, however, the speakers used in portable systems, whether internal or external, have little ability to reproduce signals below 150Hz. Applications using speakers with this limited frequency response reap little improvement by using high value input and output capacitors. Besides affecting system cost and size, Ci has an effect on the LM4809's click and pop performance. The magnitude of the pop is directly proportional to the input capacitor's size. Thus, pops can be minimized by selecting an input capacitor value that is no higher than necessary to meet the desired -3dB frequency. Please refer to the Optimizing Click and Pop Reduction Performance section for a more detailed discussion on click and pop performance. As shown in Figure 1, the input resistor, RI and the input capacitor, CI, produce a -3dB high pass filter cutoff frequency that is found using Equation (3). In addition, the output load RL, and the output capacitor CO, produce a -3db high pass filter cutoff frequency defined by Equation (4). fI-3db=1/2RICI fO-3db=1/2RLCO Although the BYPASS pin current cannot be modified, changing the size of CB alters the device's turn-on time and the magnitude of "clicks and pops". Increasing the value of CB reduces the magnitude of turn-on pops. However, this presents a tradeoff: as the size of CB increases, the turn-on time increases. There is a linear relationship between the size of CB and the turn-on time. Here are some typical turn-on times for various values of CB: (3) (4) Also, careful consideration must be taken in selecting a certain type of capacitor to be used in the system. Different types of capacitors (tantalum, electrolytic, ceramic) have unique performance characteristics and may affect overall system performance. CB TON 0.1F 80ms 0.22F 170ms 0.33F 270ms 0.47F 370ms 0.68F 490ms 1.0F 920ms 2.2F 1.8sec 3.3F 2.8sec 4.7F 3.4sec 10F 7.7sec Bypass Capacitor Value Selection Besides minimizing the input capacitor size, careful consideration should be paid to the value of CB, the capacitor connected to the BYPASS pin. Since CB determines how fast the LM4809 settles to quiescent operation, its value is critical when minimizing turn-on pops. The slower the LM4809's outputs ramp to their quiescent DC voltage (nominally 1/2 VDD), the smaller the turn-on pop. Choosing CB equal to 4.7F along with a small value of Ci (in the range of 0.1F to 0.47F), produces a click-less and pop-less shutdown function. As discussed above, choosing Ci no larger than necessary for the desired bandwith helps minimize clicks and pops. In order eliminate "clicks and pops", all capacitors must be discharged before turn-on. Rapidly switching VDD may not allow the capacitors to fully discharge, which may cause "clicks and pops". In a single-ended configuration, the output is coupled to the load by CO. This capacitor usually has a high value. CO discharges through internal 20k resistors. Depending on the size of CO, the discharge time constant can be relatively large. To reduce transients in single-ended mode, an external 1k-5k resistor can be placed in parallel with the internal 20k resistor. The tradeoff for using this resistor is increased quiescent current. OPTIMIZING CLICK AND POP REDUCTION PERFORMANCE The LM4809 contains circuitry that minimizes turn-on and shutdown transients or "clicks and pop". For this discussion, turn-on refers to either applying the power supply voltage or when the shutdown mode is deactivated. During turn-on, the LM4809's internal amplifiers are configured as unity gain buffers. An internal current source charges up the capacitor on the BYPASS pin in a controlled, linear manner. The gain of the internal amplifiers remains unity until the voltage on the BYPASS pin reaches 1/2 VDD . As soon as the voltage on Design a Dual 70mW/32 Audio Amplifier www.national.com AUDIO POWER AMPLIFIER DESIGN Given: Power Output Load Impedance Input Level Input Impedance 70 mW 32 1 Vrms (max) 20k Bandwidth 100 Hz-20 kHz 0.50dB The design begins by specifying the minimum supply voltage necessary to obtain the specified output power. One way to 12 (Continued) AV = Rf/Ri find the minimum supply voltage is to use the Output Power vs Supply Voltage curve in the Typical Performance Characteristics section. Another way, using Equation (5), is to calculate the peak output voltage necessary to achieve the desired output power for a given load impedance. To account for the amplifier's dropout voltage, two additional voltages, based on the Dropout Voltage vs Supply Voltage in the Typical Performance Characteristics curves, must be added to the result obtained by Equation (5). For a singleended application, the result is Equation (6). (8) The value of Rf is 30k. The last step in this design is setting the amplifier's -3db frequency bandwidth. To achieve the desired 0.25dB pass band magnitude variation limit, the low frequency response must extend to at lease one-fifth the lower bandwidth limit and the high frequency response must extend to at least five times the upper bandwidth limit. The gain variation for both response limits is 0.17dB, well within the 0.25dB desired limit. The results are an fL = 100Hz/5 = 20Hz (9) fH = 20kHz*5 = 100kHz (10) (5) and a VDD (2VOPEAK + (VODTOP + VODBOT)) (6) The Output Power vs Supply Voltage graph for a 32 load indicates a minimum supply voltage of 4.8V. This is easily met by the commonly used 5V supply voltage. The additional voltage creates the benefit of headroom, allowing the LM4809 to produce peak output power in excess of 70mW without clipping or other audible distortion. The choice of supply voltage must also not create a situation that violates maximum power dissipation as explained above in the Power Dissipation section. Remember that the maximum power dissipation point from Equation (1) must be multiplied by two since there are two independent amplifiers inside the package. Once the power dissipation equations have been addressed, the required gain can be determined from Equation (7). As stated in the External Components section, both Ri in conjunction with Ci, and Co with RL, create first order highpass filters. Thus to obtain the desired low frequency response of 100Hz within 0.5dB, both poles must be taken into consideration. The combination of two single order filters at the same frequency forms a second order response. This results in a signal which is down 0.34dB at five times away from the single order filter -3dB point. Thus, a frequency of 20Hz is used in the following equations to ensure that the response is better than 0.5dB down at 100Hz. Ci 1 / (2 * 20k * 20Hz) = 0.397F; use 0.39F.(11) Co 1 / (2 * 32 * 20Hz) = 249F; use 330F. (12) (7) The high frequency pole is determined by the product of the desired high frequency pole, fH, and the closed-loop gain, AV. With a closed-loop gain of 1.5 and fH = 100kHz, the resulting GBWP = 150kHz which is much smaller than the LM4809's GBWP of 900kHz. This figure displays that if a designer has a need to design an amplifier with a higher gain, the LM4809 can still be used without running into bandwidth limitations. Thus, a minimum gain of 1.497 allows the LM4809 to reach full output swing and maintain low noise and THD+N perfromance. For this example, let AV=1.5. The amplifiers overall gain is set using the input (Ri ) and feedback (Rf ) resistors. With the desired input impedance set at 20k, the feedback resistor is found using Equation (8). 13 www.national.com LM4809 Application Information LM4809 Demonstration Board Schematic 20009057 FIGURE 2. LM4809 Demonstration Board Schematic www.national.com 14 LM4809 Demonstration Board Layout 20009058 FIGURE 3. Recommended MSOP PC Board Layout Component-Side Silkscreen 20009059 FIGURE 4. Recommended MSOP PC Board Layout Component-Side Layout 20009060 FIGURE 5. Recommended MSOP PC Board Layout Bottom-Side Layout 15 www.national.com LM4809 Demonstration Board Layout (Continued) 20009062 FIGURE 6. Recommended LD PC Board Layout Component-Side Silkscreen 20009063 FIGURE 7. Recommended LD PC Board Layout Component-Side Layout 20009064 FIGURE 8. Recommended LD PC Board Layout Bottom-Side Layout www.national.com 16 LM4809 Demonstration Board Layout (Continued) 20009076 FIGURE 9. Recommended LQ PC Board Layout Component-Side Silkscreen 20009074 FIGURE 10. Recommended LQ PC Board Layout Component-Side Layout 17 www.national.com LM4809 Demonstration Board Layout (Continued) 20009075 FIGURE 11. Recommended LQ PC Board Layout Bottomt-Side Layout www.national.com 18 LM4809 Physical Dimensions inches (millimeters) unless otherwise noted Order Number LM4809MM NS Package Number MUA08A Order Number LM4809MA NS Package Number M08A 19 www.national.com LM4809 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LM4809LD NS Package Number LDA08B www.national.com 20 inches (millimeters) unless otherwise noted (Continued) Order Number LM4809LQ NS Package Number LQB08A LIFE SUPPORT POLICY NATIONAL'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems 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. 2. A critical component is any component of 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. BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ``Banned Substances'' as defined in CSP-9-111S2. National Semiconductor Americas Customer Support Center Email: new.feedback@nsc.com Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Francais Tel: +33 (0) 1 41 91 8790 National Semiconductor Asia Pacific Customer Support Center Email: ap.support@nsc.com National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: jpn.feedback@nsc.com Tel: 81-3-5639-7560 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. LM4809 Dual 105mW Headphone Amplifier with Active-Low Shutdown Mode Physical Dimensions IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI's terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI's standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using TI components. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional restrictions. Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in such safety-critical applications. TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use. TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated products in automotive applications, TI will not be responsible for any failure to meet such requirements. Following are URLs where you can obtain information on other Texas Instruments products and application solutions: Products Applications Audio www.ti.com/audio Communications and Telecom www.ti.com/communications Amplifiers amplifier.ti.com Computers and Peripherals www.ti.com/computers Data Converters dataconverter.ti.com Consumer Electronics www.ti.com/consumer-apps DLP(R) Products www.dlp.com Energy and Lighting www.ti.com/energy DSP dsp.ti.com Industrial www.ti.com/industrial Clocks and Timers www.ti.com/clocks Medical www.ti.com/medical Interface interface.ti.com Security www.ti.com/security Logic logic.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense Power Mgmt power.ti.com Transportation and Automotive www.ti.com/automotive Microcontrollers microcontroller.ti.com Video and Imaging RFID www.ti-rfid.com OMAP Mobile Processors www.ti.com/omap Wireless Connectivity www.ti.com/wirelessconnectivity TI E2E Community Home Page www.ti.com/video e2e.ti.com Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright (c) 2011, Texas Instruments Incorporated