LM231,LM331 LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters Literature Number: SNOSBI2A LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters General Description The LM231/LM331 family of voltage-to-frequency converters are ideally suited for use in simple low-cost circuits for analog-to-digital conversion, precision frequency-to-voltage conversion, long-term integration, linear frequency modulation or demodulation, and many other functions. The output when used as a voltage-to-frequency converter is a pulse train at a frequency precisely proportional to the applied input voltage. Thus, it provides all the inherent advantages of the voltage-to-frequency conversion techniques, and is easy to apply in all standard voltage-to-frequency converter applications. Further, the LM231A/LM331A attain a new high level of accuracy versus temperature which could only be attained with expensive voltage-to-frequency modules. Additionally the LM231/331 are ideally suited for use in digital systems at low power supply voltages and can provide lowcost analog-to-digital conversion in microprocessorcontrolled systems. And, the frequency from a battery powered voltage-to-frequency converter can be easily channeled through a simple photo isolator to provide isolation against high common mode levels. The LM231/LM331 utilize a new temperature-compensated band-gap reference circuit, to provide excellent accuracy over the full operating temperature range, at power supplies as low as 4.0V. The precision timer circuit has low bias currents without degrading the quick response necessary for 100 kHz voltage-to-frequency conversion. And the output are capable of driving 3 TTL loads, or a high voltage output up to 40V, yet is short-circuit-proof against VCC. Features n Guaranteed linearity 0.01% max n Improved performance in existing voltage-to-frequency conversion applications n Split or single supply operation n Operates on single 5V supply n Pulse output compatible with all logic forms n Excellent temperature stability: 50 ppm/C max n Low power consumption: 15 mW typical at 5V n Wide dynamic range, 100 dB min at 10 kHz full scale frequency n Wide range of full scale frequency: 1 Hz to 100 kHz n Low cost Connection Diagram Dual-In-Line Package 00568021 Order Number LM231AN, LM231N, LM331AN, or LM331N See NS Package Number N08E Ordering Information Device Temperature Range Package LM231N -25C TA +85C N08E (DIP) LM231AN -25C TA +85C N08E (DIP) LM331N 0C TA +70C N08E (DIP) LM331AN 0C TA +70C N08E (DIP) Teflon (R) is a registered trademark of DuPont (c) 2006 National Semiconductor Corporation DS005680 www.national.com LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters April 2006 LM231A/LM231/LM331A/LM331 Absolute Maximum Ratings Operating Ratings (Note 2) (Notes 1, 2) Operating Ambient Temperature If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. 40V Supply Voltage, VS Output Short Circuit to Ground Continuous Output Short Circuit to VCC Continuous Input Voltage -25C to +85C LM331, LM331A 0C to +70C Supply Voltage, VS +4V to +40V Package Thermal Resistance -0.2V to +VS Package Dissipation at 25C LM231, LM231A 1.25W (Note 3) Lead Temperature (Soldering, 10 sec.) Dual-In-Line Package (Plastic) Package J-A 8-Lead Plastic DIP 100C/W 260C ESD Susceptibility (Note 5) 500V Electrical Characteristics All specifications apply in the circuit of Figure 4, with 4.0V VS 40V, TA=25C, unless otherwise specified. Parameter VFC Non-Linearity (Note 4) VFC Non-Linearity in Circuit of Figure 3 Conditions Min Typ Max Units 0.003 0.006 0.024 0.01 0.02 0.14 % Full- Scale 0.95 1.00 1.05 kHz/V 0.90 1.00 1.10 kHz/V TMIN TA TMAX, 4.5V VS 20V 30 20 150 50 ppm/C ppm/C 4.5V VS 10V 0.01 0.1 %/V 10V VS 40V 0.006 0.06 %/V 4.5V VS 20V TMIN TA TMAX VS = 15V, f = 10 Hz to 11 kHz % Full- Scale %Full- Scale Conversion Accuracy Scale Factor (Gain) LM231, LM231A VIN = -10V, RS = 14 k LM331, LM331A Temperature Stability of Gain LM231/LM331 LM231A/LM331A Change of Gain with VS Rated Full-Scale Frequency VIN = -10V Gain Stability vs. Time (1000 Hours) TMIN TA TMAX Over Range (Beyond Full-Scale) Frequency VIN = -11V 10.0 kHz 0.02 % Full- Scale 10 % INPUT COMPARATOR 3 4 3 Offset Voltage LM231/LM331 TMIN TA TMAX LM231A/LM331A TMIN TA TMAX 10 14 10 mV mV mV Bias Current -80 -300 nA Offset Current 8 100 nA VCC-2.0 V 0.667 0.70 x VS 10 100 nA Common-Mode Range TMIN TA TMAX -0.2 TIMER Timer Threshold Voltage, Pin 5 Input Bias Current, Pin 5 0.63 VS = 15V All Devices 0V VPIN LM231/LM331 VPIN 5 = 10V 200 1000 nA LM231A/LM331A VPIN 5 = 10V 200 500 nA 0.22 0.5 V VSAT PIN 5 (Reset) 5 9.9V I = 5 mA CURRENT SOURCE (Pin 1) Output Current LM231, LM231A RS = 14 k, VPIN 1 =0 LM331, LM331A Change with Voltage 0V VPIN 1 10V Current Source OFF Leakage www.national.com 2 126 135 144 A 116 136 156 A 0.2 1.0 A (Continued) All specifications apply in the circuit of Figure 4, with 4.0V VS 40V, TA=25C, unless otherwise specified. Parameter Conditions Min Typ Max Units 0.02 10.0 nA 2.0 50.0 nA CURRENT SOURCE (Pin 1) LM231, LM231A, LM331, LM331A All Devices TA = TMAX Operating Range of Current (Typical) (10 to 500) A REFERENCE VOLTAGE (Pin 2) LM231, LM231A 1.76 1.89 2.02 LM331, LM331A 1.70 1.89 2.08 60 0.1 Stability vs. Temperature Stability vs. Time, 1000 Hours VDC VDC ppm/C % LOGIC OUTPUT (Pin 3) VSAT I = 5 mA 0.15 0.50 V I = 3.2 mA (2 TTL Loads), TMIN TA TMAX 0.10 0.40 V 0.05 1.0 A OFF Leakage SUPPLY CURRENT LM231, LM231A LM331, LM331A VS = 5V 2.0 3.0 4.0 mA VS = 40V 2.5 4.0 6.0 mA VS = 5V 1.5 3.0 6.0 mA VS = 40V 2.0 4.0 8.0 mA Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating the device beyond its specified operating conditions. Note 2: All voltages are measured with respect to GND = 0V, unless otherwise noted. Note 3: The absolute maximum junction temperature (TJmax) for this device is 150C. The maximum allowable power dissipation is dictated by TJmax, the junction-to-ambient thermal resistance (JA), and the ambient temperature TA, and can be calculated using the formula PDmax = (TJmax - TA) / JA. The values for maximum power dissipation will be reached only when the device is operated in a severe fault condition (e.g., when input or output pins are driven beyond the power supply voltages, or the power supply polarity is reversed). Obviously, such conditions should always be avoided. Note 4: Nonlinearity is defined as the deviation of fOUT from VIN x (10 kHz/-10 VDC) when the circuit has been trimmed for zero error at 10 Hz and at 10 kHz, over the frequency range 1 Hz to 11 kHz. For the timing capacitor, CT, use NPO ceramic, Teflon (R) , or polystyrene. Note 5: Human body model, 100 pF discharged through a 1.5 k resistor. 3 www.national.com LM231A/LM231/LM331A/LM331 Electrical Characteristics LM231A/LM231/LM331A/LM331 Functional Block Diagram 00568002 Pin numbers apply to 8-pin packages only. FIGURE 1. www.national.com 4 LM231A/LM231/LM331A/LM331 Typical Performance Characteristics (All electrical characteristics apply for the circuit of Figure 4, unless otherwise noted.) Nonlinearity Error as Precision V-to-F Converter (Figure 4) Nonlinearity Error 00568025 00568026 Nonlinearity Error vs. Power Supply Voltage Frequency vs. Temperature 00568028 00568027 Output Frequency vs. VSUPPLY VREF vs. Temperature 00568030 00568029 5 www.national.com LM231A/LM231/LM331A/LM331 Typical Performance Characteristics (Continued) 100 kHz Nonlinearity Error (Figure 5) Nonlinearity Error (Figure 3) 00568032 00568031 Input Current (Pins 6,7) vs. Temperature Power Drain vs. VSUPPLY 00568033 00568034 Nonlinearity Error, Precision F-to-V Converter (Figure 7) Output Saturation Voltage vs. IOUT (Pin 3) 00568036 00568035 www.national.com 6 PRINCIPLES OF OPERATION The LM231/331 are monolithic circuits designed for accuracy and versatile operation when applied as voltage-tofrequency (V-to-F) converters or as frequency-to-voltage (Fto-V) converters. A simplified block diagram of the LM231/ 331 is shown in Figure 2 and consists of a switched current source, input comparator, and 1-shot timer. The current pump circuit forces the voltage at pin 2 to be at 1.9V, and causes a current i=1.90V/RS to flow. For Rs=14k, i=135 A. The precision current reflector provides a current equal to i to the current switch. The current switch switches the current to pin 1 or to ground, depending upon the state of the RS flip-flop. The timing function consists of an RS flip-flop and a timer comparator connected to the external RtCt network. When the input comparator detects a voltage at pin 7 higher than pin 6, it sets the RS flip-flop which turns ON the current switch and the output driver transistor. When the voltage at pin 5 rises to 23 VCC, the timer comparator causes the RS flip-flop to reset. The reset transistor is then turned ON and the current switch is turned OFF. However, if the input comparator still detects pin 7 higher than pin 6 when pin 5 crosses 23 VCC, the flip-flop will not be reset, and the current at pin 1 will continue to flow, trying to make the voltage at pin 6 higher than pin 7. This condition will usually apply under start-up conditions or in the case of an overload voltage at signal input. During this sort of overload the output frequency will be 0. As soon as the signal is restored to the working range, the output frequency will be resumed. The output driver transistor acts to saturate pin 3 with an ON resistance of about 50. In case of over voltage, the output current is actively limited to less than 50 mA. The voltage at pin 2 is regulated at 1.90 VDC for all values of i between 10 A to 500 A. It can be used as a voltage reference for other components, but care must be taken to ensure that current is not taken from it which could reduce the accuracy of the converter. 00568004 FIGURE 2. Simplified Block Diagram of Stand-Alone Voltage-to-Frequency Converter and External Components Simplified Voltage-to-Frequency Converter The operation of these blocks is best understood by going through the operating cycle of the basic V-to-F converter, Figure 2, which consists of the simplified block diagram of the LM231/331 and the various resistors and capacitors connected to it. The voltage comparator compares a positive input voltage, V1, at pin 7 to the voltage, Vx, at pin 6. If V1 is greater, the comparator will trigger the 1-shot timer. The output of the timer will turn ON both the frequency output transistor and the switched current source for a period t=1.1 RtCt. During this period, the current i will flow out of the switched current source and provide a fixed amount of charge, Q = i x t, into the capacitor, CL. This will normally charge Vx up to a higher level than V1. At the end of the timing period, the current i will turn OFF, and the timer will reset itself. Now there is no current flowing from pin 1, and the capacitor CL will be gradually discharged by RL until Vx falls to the level of V1. Then the comparator will trigger the timer and start another cycle. The current flowing into CL is exactly IAVE = i x (1.1xRtCt) x f, and the current flowing out of CL is exactly Vx/RL . VIN/RL. If VIN is doubled, the frequency will double to maintain this balance. Even a simple V-to-F converter can provide a frequency precisely proportional to its input voltage over a wide range of frequencies. Basic Voltage-to-Frequency Converter (Figure 3) The simple stand-alone V-to-F converter shown in Figure 3 includes all the basic circuitry of Figure 2 plus a few components for improved performance. A resistor, RIN=100 k 10%, has been added in the path to pin 7, so that the bias current at pin 7 (-80 nA typical) will cancel the effect of the bias current at pin 6 and help provide minimum frequency offset. The resistance RS at pin 2 is made up of a 12 k fixed resistor plus a 5 k (cermet, preferably) gain adjust rheostat. The function of this adjustment is to trim out the gain tolerance of the LM231/331, and the tolerance of Rt, RL and Ct. For best results, all the components should be stable lowtemperature-coefficient components, such as metal-film resistors. The capacitor should have low dielectric absorption; depending on the temperature characteristics desired, NPO ceramic, polystyrene, Teflon or polypropylene are best suited. A capacitor CIN is added from pin 7 to ground to act as a filter for VIN. A value of 0.01 F to 0.1 F will be adequate in most cases; however, in cases where better filtering is required, a 1 F capacitor can be used. When the RC time constants are matched at pin 6 and pin 7, a voltage step at VIN will cause a step change in fOUT. If CIN is much less than CL, a step at VIN may cause fOUT to stop momentarily. 7 www.national.com LM231A/LM231/LM331A/LM331 Detail of Operation, Functional Block Diagram (Figure 1) The block diagram shows a band gap reference which provides a stable 1.9 VDC output. This 1.9 VDC is well regulated over a VS range of 3.9V to 40V. It also has a flat, low temperature coefficient, and typically changes less than 12% over a 100C temperature change. Applications Information LM231A/LM231/LM331A/LM331 Applications Information (Continued) Details of Operation: Precision V-To-F Converter (Figure 4) A 47 resistor, in series with the 1 F CL, provides hysteresis, which helps the input comparator provide the excellent linearity. In this circuit, integration is performed by using a conventional operational amplifier and feedback capacitor, CF. When the integrator's output crosses the nominal threshold level at pin 6 of the LM231/331, the timing cycle is initiated. The average current fed into the op-amp's summing point (pin 2) is i x (1.1 RtCt) x f which is perfectly balanced with -VIN/RIN. In this circuit, the voltage offset of the LM231/331 input comparator does not affect the offset or accuracy of the V-to-F converter as it does in the stand-alone V-to-F converter; nor does the LM231/331 bias current or offset current. Instead, the offset voltage and offset current of the operational amplifier are the only limits on how small the signal can be accurately converted. Since op-amps with voltage offset well below 1 mV and offset currents well below 2 nA are available at low cost, this circuit is recommended for best accuracy for small signals. This circuit also responds immediately to any change of input signal (which a standalone circuit does not) so that the output frequency will be an accurate representation of VIN, as quickly as 2 output pulses' spacing can be measured. 00568001 In the precision mode, excellent linearity is obtained because the current source (pin 1) is always at ground potential and that voltage does not vary with VIN or fOUT. (In the stand-alone V-to-F converter, a major cause of non-linearity is the output impedance at pin 1 which causes i to change as a function of VIN). The circuit of Figure 5 operates in the same way as Figure 4, but with the necessary changes for high speed operation. *Use stable components with low temperature coefficients. See Typical Applications section. **0.1F or 1F, See "Principles of Operation." FIGURE 3. Simple Stand-Alone V-to-F Converter with 0.03% Typical Linearity (f = 10 Hz to 11 kHz) 00568005 *Use stable components with low temperature coefficients. See Typical Applications section. **This resistor can be 5 k or 10 k for VS=8V to 22V, but must be 10 k for VS=4.5V to 8V. ***Use low offset voltage and low offset current op-amps for A1: recommended type LF411A FIGURE 4. Standard Test Circuit and Applications Circuit, Precision Voltage-to-Frequency Converter www.national.com 8 In the precision circuit, an operational amplifier provides a buffered output and also acts as a 2-pole filter. The ripple will be less than 5 mV peak for all frequencies above 1 kHz, and the response time will be much quicker than in Figure 6. However, for input frequencies below 200 Hz, this circuit will have worse ripple than Figure 6. The engineering of the filter time-constants to get adequate response and small enough ripple simply requires a study of the compromises to be made. Inherently, V-to-F converter response can be fast, but F-to-V response can not. (Continued) DETAILS OF OPERATION: F-to-V CONVERTERS (Figure 6 and Figure 7) In these applications, a pulse input at fIN is differentiated by a C-R network and the negative-going edge at pin 6 causes the input comparator to trigger the timer circuit. Just as with a V-to-F converter, the average current flowing out of pin 1 is IAVERAGE = i x (1.1 RtCt) x f. In the simple circuit of Figure 6, this current is filtered in the network RL = 100 k and 1 F. The ripple will be less than 10 mV peak, but the response will be slow, with a 0.1 second time constant, and settling of 0.7 second to 0.1% accuracy. 00568006 *Use stable components with low temperature coefficients. See Typical Applications section. **This resistor can be 5 k or 10 k for VS=8V to 22V, but must be 10 k for VS=4.5V to 8V. ***Use low offset voltage and low offset current op-amps for A1: recommended types LF411A or LF356. FIGURE 5. Precision Voltage-to-Frequency Converter, 100 kHz Full-Scale, 0.03% Non-Linearity 9 www.national.com LM231A/LM231/LM331A/LM331 Applications Information LM231A/LM231/LM331A/LM331 Applications Information (Continued) 00568007 *Use stable components with low temperature coefficients. FIGURE 6. Simple Frequency-to-Voltage Converter, 10 kHz Full-Scale, 0.06% Non-Linearity 00568008 *Use stable components with low temperature coefficients. FIGURE 7. Precision Frequency-to-Voltage Converter, 10 kHz Full-Scale with 2-Pole Filter, 0.01% Non-Linearity Maximum www.national.com 10 LM231A/LM231/LM331A/LM331 Applications Information (Continued) Light Intensity to Frequency Converter 00568009 *L14F-1, L14G-1 or L14H-1, photo transistor (General Electric Co.) or similar Temperature to Frequency Converter 00568010 Basic Analog-to-Digital Converter Using Voltage-to-Frequency Converter Long-Term Digital Integrator Using VFC 00568011 00568012 Analog-to-Digital Converter with Microprocessor 00568013 11 www.national.com LM231A/LM231/LM331A/LM331 Applications Information (Continued) Remote Voltage-to-Frequency Converter with 2-Wire Transmitter and Receiver 00568014 Voltage-to-Frequency Converter with Square-Wave Output Using / 2 Flip-Flop 00568015 Voltage-to-Frequency Converter with Isolators 00568016 www.national.com 12 LM231A/LM231/LM331A/LM331 Applications Information (Continued) Voltage-to-Frequency Converter with Isolators 00568017 Voltage-to-Frequency Converter with Isolators 00568018 Voltage-to-Frequency Converter with Isolators 00568019 13 www.national.com www.national.com 14 Schematic Diagram 00568022 LM231A/LM231/LM331A/LM331 inches (millimeters) unless otherwise noted Dual-In-Line Package (N) Order Number LM231AN, LM231N, LM331AN, or LM331N NS Package N08E 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. For the most current product information visit us at www.national.com. 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 manufactures products and uses packing materials that 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. Leadfree products are RoHS compliant. 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 LM231A/LM231/LM331A/LM331 Precision Voltage-to-Frequency Converters 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