LMH6639 190MHz Rail-to-Rail Output Amplifier with Disable General Description Features The LMH6639 is a voltage feedback operational amplifier with a rail-to-rail output drive capability of 110mA. Employing National’s patented VIP10 process, the LMH6639 delivers a bandwidth of 190MHz at a current consumption of only 3.6mA. An input common mode voltage range extending to 0.2V below the V− and to within 1V of V+, makes the LMH6639 a true single supply op-amp. The output voltage range extends to within 30mV of either supply rail providing the user with a dynamic range that is especially desirable in low voltage applications. The LMH6639 offers a slew rate of 172V/µs resulting in a full power bandwidth of approximately 28MHz. The TON value of 83nsec combined with a settling time of 33nsec makes this device ideally suited for multiplexing applications. Careful attention has been paid to ensure device stability under all operating voltages and modes. The result is a very well behaved frequency response characteristic for any gain setting including +1, and excellent specifications for driving video cables including harmonic distortion of −60dBc, differential gain of 0.12% and differential phase of 0.045˚ (VS = 5V, Typical values unless specified) n Supply current (no load) 3.6mA n Supply current (off mode) 400µA n Output resistance (closed loop 1MHz) 0.186Ω n −3dB BW (AV = 1) 190MHz n Settling time 33nsec n Input common mode voltage −0.2V to 4V n Output voltage swing 40mV from rails n Linear output current 110mA n Total harmonic distortion −60dBc n Fully characterized for 3V, 5V and ± 5V n No output phase reversal with CMVR exceeded n Excellent overdrive recovery n Off Isolation 1MHz −70dB n Differential Gain 0.12% n Differential Phase 0.045˚ Applications n n n n n Active filters CD/DVD ROM ADC buffer amplifier Portable video Current sense buffer 20030246 FIGURE 1. Typical Single Supply Schematic © 2003 National Semiconductor Corporation DS200302 www.national.com LMH6639 190MHz Rail-to-Rail Output Amplifier with Disable July 2003 LMH6639 Absolute Maximum Ratings Junction Temperature (Note 4) (Note 1) Soldering Information If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Tolerance +150˚C Infrared or Convection (20 sec) 235˚C Wave Soldering (10 sec) 260˚C 2KV (Note 2) 200V (Note 9) Operating Ratings (Note 1) ± 2.5V ± 10mA VIN Differential Input Current + − Supply Voltage (V – V ) Operating Temperature Range (Note 4) 13.5V Voltage at Input/Output pins V+ +0.8V, V− −0.8V Storage Temperature Range −65˚C to +150˚C −40˚C to +85˚C Package Thermal Resistance (θJA) (Note 4) SOT23-6 265˚C/W SOIC-8 190˚C/W 3V Electrical Characteristics Unless otherwise specified, all limits guaranteed for at TJ = 25˚C, V+ = 3V, V− = 0V, VO = VCM = V+/2, and RL = 2kΩ to V+/2. Boldface limits apply at the temperature extremes. Symbol BW Parameter −3dB BW Conditions AV = +1 Min (Note 6) Typ (Note 5) 120 170 AV = −1 0.1dB Gain Flatness RF = 2.65kΩ , RL = 1kΩ, FPBW Full Power Bandwidth AV = +1, VOUT = 2VPP, −1dB V+ = 1.8V, V− = 1.2V GBW Gain Bandwidth product AV = +1 en Input-Referred Voltage Noise RF = 33kΩ Input-Referred Current Noise RF = 1MΩ 16.4 MHz 21 MHz 83 MHz f = 10kHz 19 f = 1MHz 16 f = 10kHz 1.30 f = 1MHz 0.36 THD Total Harmonic Distortion f = 5MHz, VO = 2VPP, AV = +2, RL = 1kΩ to V+/2 TS Settling Time VO = 2VPP, ± 0.1% SR Slew Rate AV = −1 (Note 8) VOS Input Offset Voltage nV/ pA/ −50 120 Units MHz 63 BW0.1dB in Max (Note 6) dBc 37 ns 167 V/µs 1.01 5 7 mV TC VOS Input Offset Average Drift (Note 11) 8 IB Input Bias Current (Note 7) −1.02 −2.6 −3.5 µA IOS Input Offset Current 20 800 1000 nA RIN Common Mode Input Resistance AV = +1, f = 1kHz, RS = 1MΩ 6.1 MΩ CIN Common Mode Input Capacitance AV = +1, RS = 100kΩ 1.35 pF CMVR Input Common-Mode Voltage Range CMRR ≥ 50dB −0.3 1.8 1.6 2 CMRR Common Mode Rejection Ratio (Note 12) 72 93 AVOL Large Signal Voltage Gain VO = 2VPP, RL = 2kΩ to V+/2 80 76 100 VO = 2VPP, RL = 150Ω to V+/2 74 70 78 www.national.com 2 µV/˚C −0.2 −0.1 V dB dB (Continued) Unless otherwise specified, all limits guaranteed for at TJ = 25˚C, V+ = 3V, V− = 0V, VO = VCM = V+/2, and RL = 2kΩ to V+/2. Boldface limits apply at the temperature extremes. Symbol VO Parameter Output Swing High Output Swing Low ISC Output Short Circuit Current Conditions Min (Note 6) Typ (Note 5) RL = 2kΩ to V+/2, VID = 200mV 2.90 2.98 + RL = 150Ω to V /2, VID = 200mV 2.75 2.93 RL = 50Ω to V+/2, VID = 200mV 2.6 2.85 RL = 2kΩ to V+/2, VID = −200mV 25 Max (Note 6) V 75 + RL = 150Ω to V /2, VID = −200mV 75 200 RL = 50Ω to V+/2, VID = −200mV 130 300 Sourcing to V+/2, (Note 10) 50 35 120 Sinking to V+/2, (Note 10) 67 40 140 72 96 IOUT Output Current VO = 0.5V from either supply PSRR Power Supply Rejection Ratio (Note 12) IS Supply Current (Enabled) No Load mV mA 99 Supply Current (Disabled) Units mA dB 3.5 5.6 7.5 0.3 0.5 0.7 mA V+−1.59 V −13 µA On Time After Shutdown 83 nsec Off Time to Shutdown 160 nsec TH_SD Threshold Voltage for Shutdown Mode I_SD PIN Shutdown Pin Input Current TON TOFF ROUT Output Resistance Closed Loop SD Pin Connect to 0V (Note 7) RF = 10kΩ, f = 1kHz, AV = −1 27 RF = 10kΩ, f = 1MHz, AV = −1 266 mΩ 5V Electrical Characteristics Unless otherwise specified, all limits guaranteed for at TJ = 25˚C, V+ = 5V, V− = 0V, VO = VCM = V+/2, and RL = 2kΩ to V+/2. Boldface limits apply at the temperature extremes. Symbol BW Parameter −3dB BW Conditions AV = +1 Min (Note 6) Typ (Note 5) 130 190 AV = −1 Max (Note 6) Units MHz 64 BW0.1dB 0.1dB Gain Flatness RF = 2.51kΩ, RL = 1kΩ, 16.4 MHz FPBW Full Power Bandwidth AV = +1, VOUT = 2VPP, −1dB 28 MHz GBW Gain Bandwidth Product AV = +1 86 MHz en Input-Referred Voltage Noise RF = 33kΩ in Input-Referred Current Noise RF = 1MΩ f = 10kHz 19 f = 1MHz 16 f = 10KHz 1.35 f = 1MHz 0.35 nV/ pA/ THD Total Harmonic Distortion f = 5MHz, VO = 2VPP, AV = +2 RL = 1kΩ to V+/2 −60 dBc DG Differential Gain NTSC, AV = +2 RL = 150Ω to V+/2 0.12 % DP Differential Phase NTSC, AV = +2 RL = 150Ω to V+/2 0.045 deg TS Settling Time VO = 2VPP, ± 0.1% SR Slew Rate AV = −1, (Note 8) VOS Input Offset Voltage 130 33 ns 172 V/µs 1.02 3 5 7 mV www.national.com LMH6639 3V Electrical Characteristics LMH6639 5V Electrical Characteristics (Continued) Unless otherwise specified, all limits guaranteed for at TJ = 25˚C, V+ = 5V, V− = 0V, VO = VCM = V+/2, and RL = 2kΩ to V+/2. Boldface limits apply at the temperature extremes. Symbol Parameter Conditions Min (Note 6) Typ (Note 5) Max (Note 6) Units TC VOS Input Offset Average Drift (Note 11) 8 IB Input Bias Current (Note 7) −1.2 −2.6 −3.25 µA IOS Input Offset Current 20 800 1000 nA RIN Common Mode Input Resistance AV = +1, f = 1kHz, RS = 1MΩ 6.88 MΩ CIN Common Mode Input Capacitance AV = +1, RS = 100kΩ 1.32 pF CMVR Common-Mode Input Voltage Range CMRR ≥ 50dB −0.3 −0.2 −0.1 4 3.8 3.6 CMRR Common Mode Rejection Ratio (Note 12) 72 95 AVOL Large Signal Voltage Gain VO = 4VPP RL = 2kΩ to V+/2 86 82 100 VO = 3.75VPP RL = 150Ω to V+/2 74 70 77 4.90 4.97 VO Output Swing High Output Swing Low RL = 2kΩ to V+/2, VID = 200mV + RL = 150Ω to V /2, VID = 200mV 4.65 4.90 RL = 50Ω to V+/2, VID = 200mV 4.40 4.77 100 85 200 190 400 Sourcing to V+/2, (Note 10) 100 79 160 Sinking from V+/2, (Note 10) 120 85 190 IOUT Output Current VO = 0.5V from either supply Power Supply Rejection Ratio (Note 12) IS Supply Current (Enabled) No Load I_SD PIN Shutdown Pin Input Current TON On Time after Shutdown TOFF Off Time to Shutdown ROUT Output Resistance Closed Loop www.national.com SD Pin Connected to 0V (Note 7) dB 3.6 5.8 8.0 0.40 0.8 1.0 mA V −30 µA 83 nsec 160 nsec RF = 10kΩ, f = 1kHz, AV = −1 29 RF = 10kΩ, f = 1MHz, AV = −1 253 4 mA 96 V+ −1.65 mV mA 110 72 Supply Current (Disabled) Threshold Voltage for Shutdown Mode V 25 PSRR TH_SD dB RL = 150Ω to V+/2, VID = −200mV RL = 50Ω to V /2, VID = −200mV Output Short Circuit Current V dB RL = 2kΩ to V+/2, VID = −200mV + ISC µV/˚C mΩ Symbol BW BW0.1dB Parameter −3dB BW 0.1dB Gain Flatness Conditions AV = +1 Min (Note 6) Typ (Note 5) 150 228 Max (Note 6) Units MHz AV = −1 65 RF = 2.26kΩ, RL = 1kΩ 18 MHz FPBW Full Power Bandwidth AV = +1, VOUT = 2VPP, −1dB 29 MHz GBW Gain Bandwidth Product AV = +1 90 MHz en Input-Referred Voltage Noise RF = 33kΩ in Input-Referred Current Noise RF = 1MΩ f = 10kHz 19 f = 1MHz 16 f = 10kHz 1.13 f = 1MHz 0.34 nV/ pA/ THD Total Harmonic Distortion f = 5MHz, VO = 2VPP, AV = +2, RL = 1kΩ −71.2 dBc DG Differential Gain NTSC, AV = +2 RL = 150Ω 0.11 % DP Differential Phase NTSC, AV = +2 RL = 150Ω 0.053 deg TS Settling Time VO = 2VPP, ± 0.1% 33 ns AV = −1 (Note 8) SR Slew Rate VOS Input Offset Voltage 140 200 1.03 V/µs 5 7 mV TC VOS Input Offset Voltage Drift (Note 11) 8 IB Input Bias Current (Note 7) −1.40 −2.6 −3.25 µA IOS Input Offset Current 20 800 1000 nA RIN Common Mode Input Resistance AV +1, f = 1kHz, RS = 1MΩ 7.5 MΩ CIN Common Mode Input Capacitance AV = +1, RS = 100kΩ 1.28 pF CMVR Common Mode Input Voltage Range CMRR ≥ 50dB −5.3 3.8 3.6 4.0 CMRR Common Mode Rejection Ratio (Note 12) 72 95 AVOL Large Signal Voltage Gain VO = 9VPP, RL = 2kΩ 88 84 100 VO = 8VPP, RL = 150Ω 74 70 77 VO Output Swing High Output Swing Low ISC Output Short Circuit Current RL = 2kΩ, VID = 200mV 4.85 4.96 RL = 150Ω, VID = 200mV 4.55 4.80 RL = 50Ω, VID = 200mV 3.60 µV/˚C −5.2 −5.1 dB dB V 4.55 RL = 2kΩ, VID = −200mV −4.97 RL = 150Ω, VID = −200mV −4.85 −4.55 RL = 50Ω, VID = −200mV −4.65 −4.30 Sourcing to Ground, (Note 10) 100 80 168 Sinking to Ground, (Note 10) 110 85 190 5 V −4.90 V mA www.national.com LMH6639 ± 5V Electrical Characteristics Unless otherwise specified, all limits guaranteed for at TJ = 25˚C, VSUPPLY = ± 5V, VO = VCM = GND, and RL = 2kΩ to V+/2. Boldface limits apply at the temperature extremes. LMH6639 ± 5V Electrical Characteristics (Continued) Unless otherwise specified, all limits guaranteed for at TJ = 25˚C, VSUPPLY = ± 5V, VO = VCM = GND, and RL = 2kΩ to V+/2. Boldface limits apply at the temperature extremes. Symbol Parameter Conditions IOUT Output Current VO = 0.5V from either supply PSRR Power Supply Rejection Ratio (Note 12) IS Supply Current (Enabled) No Load Min (Note 6) Typ (Note 5) Max (Note 6) Units 112 72 Supply Current (Disabled) mA 96 dB 4.18 6.5 8.5 0.758 1.0 1.3 mA V+ − 1.67 V TH_SD Threshold Voltage for Shutdown Mode I_SD PIN Shutdown Pin Input Current −84 µA TON On Time after Shutdown 83 nsec TOFF Off Time to Shutdown 160 nsec ROUT Output Resistance Closed Loop SD Pin Connected to −5V (Note 7) RF = 10kΩ, f = 1kHz, AV = −1 32 RF = 10kΩ, f = 1MHz, AV = −1 226 mΩ Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics. Note 2: Human body model, 1.5kΩ in series with 100pF. Note 3: Applies to both single-supply and split-supply operation. Continuous short circuit operation at elevated ambient temperature can result in exceeding the maximum allowed junction temperature of 150˚C. Note 4: The maximum power dissipation is a function of TJ(MAX), θJA, and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(MAX) - TA)/ θJA . All numbers apply for packages soldered directly onto a PC board. Note 5: Typical values represent the most likely parametric norm. Note 6: All limits are guaranteed by testing or statistical analysis. Note 7: Positive current corresponds to current flowing into the device. Note 8: Slew rate is the average of the rising and falling slew rates. Note 9: Machine Model, 0Ω in series with 200pF. Note 10: Short circuit test is a momentary test. Note 11: Offset voltage average drift determined by dividing the change in VOS at temperature extremes into the total temperature change. Note 12: f ≤ 1kHz (see typical performance Characteristics) Connection Diagrams SOT23-6 SOIC-8 20030202 20030201 Top View Top View Ordering Information Package 6-Pin SOT-23 Part Number Package Marking Transport Media NSC Drawing LMH6639MF A81A 1k Units Tape and Reel MF06A LMH6639MFX 8-Pin SOIC LMH6639MA 3k Units Tape and Reel LMH6639MA LMH6639MAX www.national.com Rails 2.5k Units Tape and Reel 6 M08A At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, RF = 1kΩ for AV = −1. Unless otherwise specified. Output Sourcing Saturation Voltage vs. IOUT for Various Temperature Output Sinking Saturation Voltage vs. IOUT for Various Temperature 20030237 20030239 Negative Output Saturation Voltage vs. VSUPPLY for Various Temperature Positive Output Saturation Voltage vs. VSUPPLY for Various Temperature 20030234 20030233 VOUT from V+ vs. ISOURCE VOUT from V− vs. ISINK 20030238 20030236 7 www.national.com LMH6639 Typical Performance Characteristics LMH6639 Typical Performance Characteristics At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, RF = 1kΩ for AV = −1. Unless otherwise specified. (Continued) IOS vs. VS for Various Temperature VOS vs. VS for 3 Representative Units 20030232 20030245 VOS vs. VS for 3 Representative Units VOS vs. VS for 3 Representative Units 20030244 20030243 VOS vs. VS for 3 Representative Units ISUPPLY vs. VCM for Various Temperature 20030242 www.national.com 20030240 8 RF = 1kΩ for AV = −1. Unless otherwise specified. (Continued) ISUPPLY vs. VS for Various Temperature IB vs. VS for Various Temperature 20030241 20030235 Bandwidth for Various VS Bandwidth for Various VS 20030206 20030205 Gain vs. Frequency Normalized Gain vs. Frequency Normalized 20030207 20030208 9 www.national.com LMH6639 Typical Performance Characteristics At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, LMH6639 Typical Performance Characteristics At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, RF = 1kΩ for AV = −1. Unless otherwise specified. (Continued) Gain and phase vs. Frequency for Various Temperature 0.1dB Gain Flatness 20030209 20030204 Frequency Response vs. Temperature Harmonic Distortion 20030210 20030269 Differential Gain/Phase On-Off Switching DC Voltage 20030211 20030270 www.national.com 10 RF = 1kΩ for AV = −1. Unless otherwise specified. (Continued) On-Off Switching 10MHz Slew Rate (Positive) 20030212 20030214 Slew Rate (Negative) On-Off Switching of Sinewave 20030213 20030215 Power Sweep CMRR vs. Frequency 20030216 20030218 11 www.national.com LMH6639 Typical Performance Characteristics At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, LMH6639 Typical Performance Characteristics At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, RF = 1kΩ for AV = −1. Unless otherwise specified. (Continued) PSRR vs. Frequency Current Noise 20030217 20030220 Voltage Noise Closed Loop Output Resistance vs. Frequency 20030221 20030219 Off Isolation Small Signal Pulse Response (AV = +1, RL = 2k ) 20030250 20030222 www.national.com 12 RF = 1kΩ for AV = −1. Unless otherwise specified. (Continued) Small Signal Pulse Response (AV = −1) Large Signal Pulse Response (RL = 2k) 20030249 20030226 Large Signal Pulse Response Large Signal Pulse Response 20030227 20030228 13 www.national.com LMH6639 Typical Performance Characteristics At TJ = 25˚C, V+ = +2.5, V− = −2.5V, RF = 330Ω for AV = +2, LMH6639 In the circuit of Figure 2, the outputs of IC1 and IC2 are tied together such that their output impedances are placed in parallel at the input of IC3. The output impedance of the disabled amplifier is high compared both to the output impedance of the active amplifier and the 330Ω gain setting resistors. The closed loop output resistance for the LMH6639 is around 0.2Ω. Thus the active state amplifier output impedance dominates the input node to IC3, while the disabled amplifier is assured of a high level of suppression of unwanted signals which might be present at the output. Application Notes MULTIPLEXING 5 AND 10MHz The LMH6639 may be used to implement a circuit which multiplexes two signals of different frequencies. Three LMH6639 high speed op-amps are used in the circuit of Figure 2 to accomplish the multiplexing function. Two LMH6639 are used to provide gain for the input signals, and the third device is used to provide output gain for the selected signal. SHUTDOWN OPERATION With SD pin left floating, the device enters normal operation. However, since the SD pin has high input impedance, it is best tied to V+ for normal operation. This will avoid inadvertent shutdown due to capacitive pick-up from nearby nodes. LMH6639 will typically go into shutdown when SD pin is more than 1.7V below V+, regardless of operating supplies. The SD pin can be driven by push-pull or open collector (open drain) output logic. Because the LMH6639’s shutdown is referenced to V+, interfacing to the shutdown logic is rather simple, for both single and dual supply operation, with either form of logic used. Typical configurations are shown in Figure 4 and Figure 5 below for push-pull output: 20030247 Note: Pin numbers pertain to SOIC-8 package FIGURE 2. Multiplexer Multiplexing signals “FREQ 1” and “FREQ 2” exhibit closed loop non-inverting gain of +2 each based upon identical 330Ω resistors in the gain setting positions of IC1 and IC2. The two multiplexing signals are combined at the input of IC3, which is the third LMH6639. This amplifier may be used as a unity gain buffer or may be used to set a particular gain for the circuit. 20030271 FIGURE 4. Shutdown Interface (Single Supply) 20030248 FIGURE 3. Switching between 5 and 10MHz 1k resistors are used to set an inverting gain of −1 for IC3 in the circuit of Figure 2. Figure 3 illustrates the waveforms produced. The upper trace shows the switching waveform used to switch between the 5MHz and 10MHz multiplex signals. The lower trace shows the output waveform consisting of 5MHz and 10MHz signals corresponding to the high or low state of the switching signal. www.national.com 20030272 FIGURE 5. Shutdown Interface (Dual Supplies) Common voltages for logic gates are +5V or +3V. To ensure proper power on/off with these supplies, the logic should be able to swing to 3.4V and 1.4V minimum, respectively. 14 PCB LAYOUT CONSIDERATION AND COMPONENTS SELECTION (Continued) LMH6639’s shutdown pin can also be easily controlled in applications where the analog and digital sections are operated at different supplies. Figure 6 shows a configuration where a logic output, SD, can turn the LMH6639 on and off, independent of what supplies are used for the analog and the digital sections: Care should be taken while placing components on a PCB. All standard rules should be followed especially the ones for high frequency and/ or high gain designs. Input and output pins should be separated to reduce cross-talk, especially under high gain conditions. A groundplane will be helpful to avoid oscillations. In addition, a ground plane can be used to create micro-strip transmission lines for matching purposes. Power supply, as well as shutdown pin de-coupling will reduce cross-talk and chances of oscillations. Another important parameter in working with high speed amplifiers is the component values selection. Choosing high value resistances reduces the cut-off frequency because of the influence of parasitic capacitances. On the other hand choosing the resistor values too low could "load down" the nodes and will contribute to higher overall power dissipation. Keeping resistor values at several hundreds of ohms up to several kΩ will offer good performance. National Semiconductor suggests the following evaluation boards as a guide for high frequency layout and as an aid in device testing and characterization: 20030273 FIGURE 6. Shutdown Interface (Single Supply, Open Collector Logic) The LMH6639 has an internal pull-up resistor on SD such that if left un-connected, the device will be in normal operation. Therefore, no pull-up resistor is needed on this pin. Another common application is where the transistor in Figure 6 above, would be internal to an open collector (open drain) logic gate; the basic connections will remain the same as shown. Device Package Evaluation Board PN LMH6639MA 8-Pin SOIC CLC730027 LMH6639MF SOT23-6 CLC730116 These free evaluation boards are shipped when a device sample request is placed with National Semiconductor. For normal operation, tie the SD pin to V+. 15 www.national.com LMH6639 Application Notes LMH6639 Physical Dimensions inches (millimeters) unless otherwise noted 6-Pin SOT23 NS Package Number MF06A 8-Pin SOIC NS Package Number M08A www.national.com 16 LMH6639 190MHz Rail-to-Rail Output Amplifier with Disable Notes 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. National Semiconductor Americas Customer Support Center Email: [email protected] Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 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. National Semiconductor Asia Pacific Customer Support Center Email: [email protected] National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: [email protected] 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.