Application Report Application Report 应用报告 Application Report SLAA414 – July 2009 年 ZHCA089–2009 7月 SLAA414 July2009 2009 SLAA414 ––July LDO PSRR Measurement Simplified LDO PSRR 测量简化说明 LDOPSRR PSRRMeasurement Measurement Simplified LDO Simplified Sanjay Pithadia and Scot Lester .................................................................... PMP - LP Linear Regulators 和Regulators PMP – 低压线性稳压器 Sanjay Pithadia Scot Lester Sanjay Pithadiaand andScot ScotLester Lester.................................................................... ....................................................................作者： PMP LPLinear LinearRegulators Sanjay Pithadia PMP - -LP ABSTRACT ABSTRACT This application report explains ABSTRACT different methods of measuring the Power Supply This application report explains different methods of measuring measuring the Power Power Supply 摘要 Rejection Ratio (PSRR) of a Low-Dropout (LDO) of regulator and the includes theSupply pros and This application report explains different methods Rejection Ratio (PSRR) of a Low-Dropout (LDO) regulator and includes the pros and cons of these measuring methods. Rejection Ratio (PSRR) of a Low-Dropout (LDO) regulator and includes the pros and 本应用报告解释了测量低压差 (LDO) 稳压器的电源抑制比 (PSRR) 的不同测量方法以及这些测量方法的优点 consofofthese thesemeasuring measuringmethods. methods. cons 及缺点。 What is PSRR? What PSRR? What isisPSRR? Power Supply Rejection Ratio or Power Supply Ripple Rejection (PSRR) is a measure of a circuit’s power 什么是 PSRR? Power Supply Rejection Ratiooror Power Supply RippleRejection Rejection (PSRR) ameasure measure circuit’s power supply’s rejection expressed as a logSupply ratio ofRipple output noise to input noise. provides a measure of Power Supply Rejection Ratio Power (PSRR) isisaPSRR ofofaacircuit’s power 电源抑制比或电源纹波抑制 是一个电路的电源抑制能力的度量值，表示为输出噪声与输入噪声的对数之比。 提供了 (PSRR)ripple, supply’s rejection expressed asaalog log ratioofofoutput outputnoise noiseto toinput inputnoise. noise. PSRR provides ameasure measure offrom how well a circuit rejects of ratio various frequencies, injected at its input. The ripple acan bePSRR either supply’s rejection expressed as PSRR provides of 一个电路对从它的输入处引入的不同频率的纹波抑制能力的度量值。纹波可以来自输入电源，比如一个 的电源纹波， how well circuit rejects ripple, varioussupply frequencies, injectedatatripple input. The ripple50Hz/60Hz canbe beeither either from the input supply such ripple, as a 50Hz/60Hz ripple,injected switching from a DC/DC converter, orfrom ripple how well aacircuit rejects ofofvarious frequencies, itsitsinput. The ripple can thedue input supply such asan 50Hz/60Hz supply ripple, switching ripple from DC/DC converter, ripple 也可以是来自 转换器的开关纹波，还可以是由于输入电压被电路板上不同的电路块共用所致。在 tosupply the sharing of input supply between different circuit blocks onaathe board. InLDO the的情况下， case of LDOs, the input such as aa50Hz/60Hz supply ripple, switching ripple from DC/DC converter, ororripple DC/DC PSRR due theis sharing anof input supply between differentcircuit circuitcompared blockson onthe board. thecase case LDOs, PSRR a measure the supply regulated output voltage ripple tothe the inputInIn voltage ripple over a wide due totothe sharing ofofan input different blocks board. the ofof(dB) LDOs, 是一个在较大的频率范围内（通常为 ），稳定的输出电压纹波相比于输入电压纹波的度量值，用分贝 来表示 10Hz 至between 1MHz PSRR measure theregulated output voltage ripple compared to the input voltage ripple over a wide frequency range (10Hz toregulated 1MHz is common) and is expressed in decibels (dB). The PSRR is very critical PSRR isisaameasure ofofthe output voltage ripple compared to the input voltage ripple over a wide 其大小。在许多音频和射频应用中， 是一个非常重要的参数。 PSRR frequency range (10Hzaudio 1MHz iscommon) common) andisisexpressed expressedinindecibels decibels(dB). (dB).The ThePSRR PSRRisisvery verycritical critical parameter in many andisRF applications. frequency range (10Hz toto1MHz and parameter in many audio and RF applications. parameter in many audio and RF applications. 计算The 的基本公式是： PSRR basic equation for PSRR is: The basic equationfor forPSRR PSRR The basic equation is:is: Ripple Input PSRR = 20 log RippleInput Ripple Input Ripple Output PSRR==20 20log log PSRR (1) RippleOutput Ripple Output (1) (1) 在过去， 性能，但目前 已经拥有了在 5MHz 下 PSRR >TI 的 LDO > LDO 稳压器件都具有较差的高频 TI performance, 40dB LDO。在 TI PSRR Historically LDOs have poor highPSRR frequency PSRR but currently has的LDOs with 数据表中，关于 曲线图很重要的一点是， 的坐标轴是反向的（如图 所示）。 被计算为抑制能力，因此它本应 Historically LDOs have poor high frequency PSRR performance, but currently TI has LDOs with PSRR PSRR PSRR 1 PSRR 40dB at LDOs 5MHz.have One poor important point regarding PSRR graphs TI LDO TI datasheet is that PSRR Historically high frequency PSRRthe performance, butincurrently has LDOs with the PSRR >> 40dB at 5MHz. One important point regarding the PSRR graphs in TI LDO datasheet is that the PSRR 是个负数；然而，图中显示它是一个正数，这说明一个更高的数值表示了更高的噪声抑制。 axis inverted Figurepoint 1). The PSRR the is calculated as rejection so itdatasheet should beisathat negative number; 40dB at is 5MHz. One(See important regarding PSRR graphs in TI LDO the PSRR axis inverted (See Figure 1). Thepositive PSRRisnumber iscalculated calculated asrejection soititshould should beaahigher negative number; however, the(See graph shows itThe as so that arejection higher so number denotes noise rejection. axis isisinverted Figure 1). PSRR as be negative number; however, the graph shows it as positive number so that a higher number denotes higher noise rejection. however, the graph shows it as positive number so that a higher number denotes higher noise rejection. 80 8080 150�mA 150�mA 150�mA 70 7070 60 10�mA 10�mA 10�mA PSRR�-�dB PSRR – dB PSRR�-�dB PSRR�-�dB 6060 50 5050 40 4040 75�mA 75�mA 75�mA 30 3030 20 2020 COUT =�1 �F, �F, =�1 CC =�1 �F, CNR =�10�nF OUT OUT =�10�nF CC =�10�nF NR NR 10 1010 0 0 0 10 1010 100 100 100 1�k 10�k 100�k 1�M f�-�Frequency�-�Hz 1�k 10�k 100�k 1�M 1�k 10�k 100�k 1�M f�-�Frequency�-�Hz f�-�Frequency�-�Hz f – 频率 - Hz 10�M 10�M 10�M Figure 1. PSRR Graph of TPS717xx LDOs Figure1.1.图 PSRR Graph TPS717xx LDOs Figure PSRR Graph ofof的 TPS717xx LDOs 1. TPS717xx LDO PSRR 曲线图 SLAA414 – July 2009 Submit Documentation SLAA414 July2009 2009 年 7 月 Feedback SLAA414 ––– July ZHCA089 2009 SubmitDocumentation DocumentationFeedback Feedback Submit 提交文档反馈 LDO PSRR Measurement Simplified 1 测量简化说明 1 LDO PSRR Measurement Simplified 1 LDO PSRR LDO PSRR Measurement Simplified 1 Measuring PSRR of LDO www.ti.com Measuring PSRR of LDO The following 的PSRR 测量 LDO Measuring PSRR ofsections LDO explain different methods of measuring the PSRR of an LDO. www.ti.com www.ti.com 1. Measuring PSRR using LC summing node method: 的PSRRPSRR 测量 of LDO Measuring LDO The basic method of measuring PSRR is shown in Figure 2. In this method, DC voltage and AC The following sectionsLDO explain different methods measuring the PSRR ofthe an operating LDO. 以下各节解释了测量一个 的PSRR 的不同方法： voltages are summed together and applied at theofinput of the LDO. VDC is point bias voltage and VAC is the noise source used in the test. Capacitor C prevents VAC from shoring VDC 1.1. 使用 Measuring PSRR using LC总和节点法测量 PSRR：LC summing node method: and inductor L prevents VDC from shorting VAC. So L and C are used for isolating both the sources, 测量 的基本方法如图 所示。在这个方法中，直流电压和交流电压合在一起作为 对VDC产生 ThePSRR basic method of measuring PSRR is shown in Figure 2. In this method, DC voltage and AC LDO的输入。电容 C防止 VAC VDC and VAC, from each2 other. voltages are summed together and applied at the input of the LDO. VDC is the operating point bias 高脉冲影响，电感L防止VDC令VAC发生短路。因此L和C用于隔离两个电源，VDC和VAC。 Thevoltage L and Cand willVAC create a high pass filter used for VAC which will limit howClow in frequency we can measure is the noise source in the test. Capacitor prevents VAC from shoring VDC 和C形成一个针对于 点由公式point VAC的高通滤波器，将限制我们所能测量的 PSRR的最低频率。这个滤波器的 2确定。低于 the Land PSRR. The 3dB point ofVDC this filter determined Frequencies below3dB the inductor L prevents fromisshorting VAC.by SoEquation L and C2. are used for isolating both3dB the sources, 点的频率将被减弱，使得测量变得更加困难。能被测量的最高频率由 和C的自谐振频率所确定。 will 3dB start to beVAC, attenuated which will make measurements moreLdifficult. The highest frequency that can VDC and from each other. be measured is determined by the self resonant frequencies of the L and C components. The L and C will create a high pass filter for VAC which will limit how low in frequency we can measure Fthe 1/ 2Ȇ ¥LC (2) PSRR. The 3dB point of this filter is determined by Equation 2. Frequencies below the 3dB point min = will start to be attenuated which will make measurements more difficult. The highest frequency that A drawback to this method is that it works well only for mid-range frequencies (approximately 1 kHz to can be measured is determined by the self resonant frequencies of the L and C components. 500这种方法的缺点是，它只对中频范围内（大约 kHz). 1 kHz 至 500 kHz）的测量是有效的。 Fmin = 1/ 2Ȇ ¥LC VIN (2) VOUT A drawback to this method is that it works well only for mid-range frequencies (approximately 1 kHz to LDO 500 kHz). L VIN VIN CIN L VAC C + + VDC VOUT COUT GND LDO + + C VDC VOUT VIN CIN LOAD VOUT GND COUT LOAD VAC Figure 2. Basic Method of Measuring PSRR of LDO 2 2. Measuring PSRR using summing amplifier To improve the measurement of PSRR, a recommended method is described using a high-bandwidth Figure 2. Basic of Measuring PSRR of LDO 图 Method 测量 and 的 PSRR的基本方法 amplifier as summing node to inject the2.signalsLDO provides the isolation between VAC and VDC. This method is tested and verified using TPS72715 2. PSRR 2.使用和放大器法测量 Measuring PSRR using summing amplifier LDO and THS3120 high-speed amplifier from Texas Instruments. The basic set-up is shown in Figure 3. The PSRR is measured with a no-load condition 为了改进 PSRR 的测量方法，推荐的方法是，使用一个高带宽放大器作为总和节点来输入信号并提供 VACa和high-bandwidth VDC 之间的隔离。 To improve the measurement of PSRR, a recommended method is described using and the resulting measured PSRR graph corresponds with the datasheet graph of PSRR. amplifier as summing to inject the signals and provides the isolation between3所示。 VAC PSRR and VDC. This 德州仪器使用 和 THS3120 高速放大器对这一方法进行了测试和验证。基本结构如图 在无负载的 TPS72715 LDOnode Keep in mind the following while measuring the PSRR using this method: method is tested and verified using TPS72715 LDO and THS3120 high-speed amplifier from Texas 条件下进行测量，而测量结果图与数据表中的 PSRR 结果图相一致。 Instruments. The basic set-up is shown in Figure 3. The is measured with athis no-load condition a. The input capacitor of LDO should be removed before thePSRR measurement because capacitor 当使用此方法测量 时，请记住以下几点： PSRR and the resulting measured PSRR graph could cause the high-speed amplifier to gocorresponds unstable. with the datasheet graph of PSRR. 在测量前，应去掉 的输入电容，因为它将引起高速放大器的不稳定。 LDO Keep in Vout mind should the following while measuring the PSRR using this(either method: b.a. Vin and be measured with high-impedance probes scope or network analyzer) 当测量 Vin 和 Vout 时，应使用高阻抗探头（示波器或网络分析仪）迅速接触 或 Vout 引脚，以便使探头电感的影响降至最 低。 b. immediately Vin at the Vin or Vout pins to minimize the set-up inductance effects. a. The input capacitor of LDO should be removed before the measurement because this capacitor 在这里测试探头不应具有过长的导线，否则将增大电感并影响测量结果。 c.c. There testcause set-upthe should not have any long since this will add inductance and impact the could high-speed amplifier to wires go unstable. 当确定交流及直流输入的数值时，应考虑以下条件： d. results. b. Vin and Vout should be measured with high-impedance probes (either scope or network analyzer) d. While selecting+ the values ofVABS AC and DC thethe following immediately at the Vin 的 or Vout pins to inputs, minimize set-up conditions inductanceshould effects.be considered: （最大值） （最大值） VAC VDC < LDO VAC (max) + VDC < V (max) of LDO c.VDC There test set-up should not have any long wires since this will add inductance and impact the – VAC > LDO 的 VUVLO ABS results. VDC – VAC > VUVLO of LDO 此外，若满足以下条件，将会得到最好结果： A d. Also, While selecting the values ofobtained AC and DC following conditions should be considered: best+ Vdo results beVout if: inputs, the 这里 是 LDO 的输出电压， VDC–VACthe > Vout + 0.5will Vdo 是工作点的额定压降。 VAC (max) + + VDC (max) Vout of LDO VDC–VAC>Vout Vdo<+V0.5 is the voltage of the LDO and Vdo is the ABS where 的 output 将会过小而无法在 e. 在非常高的频率下，放大器的响应将开始减弱应用于 LDO VAC信号。在某些时候，被减弱的 VAC LDO specified drop out voltage at the operating point. VDC – VAC > V of LDO UVLO 的输出端测到。 e. At veryAlso, high frequencies, the will response of the if: amplifier will start to attenuate the VAC signal that is the best results be obtained f. 随着负载电流的增加，LDO 的开环输出阻抗将会减小（因为 MOSFET 的输出阻抗与漏电流成反比），从而降低增益。增加 appliedVDC–VAC>Vout to the LDO. At some point, the attenuated will bevoltage too small to measure theisoutput + Vdo + 0.5 where Vout isVAC the output of the LDO andonVdo the 负载电流也会将输出极点推向更高的频率，从而增大了反馈回路的带宽。负载的增加带来的实际效果是，减小了更低频率的 of the LDO. specified drop out voltage at the operating point. （由于增益的减小），而增大了更高频率的 。 PSRR f. As load current thethe open-loop output of start LDO to decreases a MOSFET e. At very high increases, frequencies, responsePSRR of theimpedance amplifier will attenuate(Since the VAC signal that is output impedance is inversely proportional to the drain current), thus lowering the gain. applied to the LDO. At some point, the attenuated VAC will be too small to measureIncreasing on the output the of load thecurrent LDO. also pushes the output pole to higher frequencies, which increases the feedback f. As load current increases, the open-loop output impedance of LDO decreases (Since a MOSFET output impedance gain. –Increasing LDO PSRR Measurement Simplifiedis inversely proportional to the drain current), thus lowering the SLAA414 July 2009 the load current also pushes the output pole to higher frequencies, which increases the feedback Submit Documentation Feedback 测量简化说明 PSRR 2 2 LDOLDO PSRR Measurement Simplified 年 2009 ZHCA089 – 2009 7月 SLAA414 – July 提交文档反馈 Submit Documentation Feedback Measuring PSRR Using Oscilloscope Measuring PSRR Using Oscilloscope www.ti.com Measuring PSRR Using Oscilloscope www.ti.com www.ti.com 用示波器测量 www.ti.comPSRR loop bandwidth. The net effect of increasing the load is therefore reduced PSRR at lower loopfrequencies bandwidth. TheThe net net effect of increasing the the load is therefore reduced PSRR at lower (because of reduced along withload increased PSRR at higher frequencies. loop bandwidth. effect of gain) increasing is therefore reduced PSRR at lower frequencies (because of reduced gain) along with increased PSRR at higher frequencies. frequencies (because of reduced gain) along with increased PSRR at higher frequencies. High�Impedance Adapters�(Model�#�41802A from Agilent) Adapters�(Model�#�41802A from Agilent) CH2 High�Impedance High�Impedance Adapters�(Model�#�41802A from Agilent) CH2CH1 CH2 CH1 CH1 1�k� 1�k�1�k� +10�V 100 �F 1�k� +10�V +10�V 100 � F RF�out 100 �F 1�k�1�k� FB* RF�out RF�out - THS3120 FB* FB* DUT 100 � DUTDUT 100 � THS3120 100 � THS3120 DC�out + DC�out + + DC�out -10�V -10�V-10�V Network Analyzer Network Built�on�THS3120�EVM Network Analyzer (Model�# Analyzer Built�on�THS3120�EVM Built�on�THS3120�EVM FB* � Ferrite�Bead�having�impedance�of 4395A from (Model�# (Model�# 10Ferrite�Bead�having�impedance�of � @�100�MHz Agilent) FB* � 4395A from FB* � Ferrite�Bead�having�impedance�of 4395A from 10 � 10 @�100�MHz Agilent) � @�100�MHz Agilent) COUT COUT C OUT Figure 3. of Measuring PSRR of LDO 图Recommended 的Method 的推荐方法 3. 测量 LDOMethod PSRR Figure 3. Recommended of Measuring PSRR of LDO Figure 3. Recommended Method of Measuring PSRR of LDO Figure 4 shows the PSRR graph measured with this method. 图 4 显示的是使用这种方法测量 PSRR 的结果图。 Figure 4 shows the the PSRR graph measured withwith this this method. Figure 4 shows PSRR graph measured method. Figure 4. PSRR Measured With Recommended Method Figure 4. Measured With Recommended 图PSRR 使用推荐方法测量所得到的 Figure 4. Measured With Recommended Method 4. PSRR PSRRMethod The THS3120 is suitable for measuring PSRR up to VDC = 5V, Frequency = 10MHz and Iload = The400mA. THS3120 is suitable for VDC measuring PSRR up to = 5V, Frequency = 10MHz andand IloadI= 适用于测量最大值为 THS3120 = 5V, Frequency = 10MHz The THS3120 is suitable for measuring PSRR upVDC to并且 VDC = 5V, Frequency = 10MHz load = 400mA. 的 。 Iload = 400mA PSRR 400mA. Measuring PSRR Using Oscilloscope Measuring PSRR Using Oscilloscope Measuring PSRR Using Oscilloscope 用示波器测量 PSRR If the user does not have a network analyzer then there is a simpler but more cumbersome method which If the user does not have a network analyzer thenthen there istoameasure but more cumbersome method which uses auser signal generator, DC source and oscilloscope the but PSRR. An AC signal from signal If如果用户没有网络分析仪，那么一个更简单但更麻烦的方法是使用一个信号发生器、直流电源和示波器来测量 the does not have a network analyzer there issimpler a simpler more cumbersome method 。 which PSRR uses a signal generator, DC source and oscilloscope to measure the PSRR. An AC signal from signal generator is applied along with DC signal at the input of the LDO, as shown in either of the afore uses a signal generator, DC source and oscilloscope to measure the PSRR. An AC signal from signal 用信号发生器产生一个交流信号，与直流信号一起作为 的输入，这与前面所提到的方法是一样的，然后用一个 LDO generator is applied along with DC signal input of the LDO, in either the afore mentioned and the output of at thethe LDO isinput measured onasanshown oscilloscope atofdifferent VAC generator ismethods, applied along with DC signal at the of the LDO, as shown in either of the afore 示波器以不同频率来测量 的输出。 由公式 计算得到，其中 是输入交流信号的幅度，而 LDO PSRR 1 Ripple(input) mentioned methods, and the output of the LDO is measured on an oscilloscope at different VAC frequencies. The PSRR calculated the Equation 1 where Ripple is the amplitude of the input mentioned methods, andisthe output ofusing the LDO is measured on an oscilloscope at different VAC (input) frequencies. PSRR is calculated using the Equation 1 where Ripple is the amplitude of the input 重复以上测量过程，以产生 曲线图片段。 (input) Ripple(output) VAC PSRR AC signalThe and是输出信号的幅度。以不同频率的 Ripple is the amplitude of output signal. This is then repeated at different frequencies frequencies. The PSRR is calculated using the Equation 1 where Ripple is the amplitude of the input (output) (input) AC of signal and Ripple is the amplitude of output signal. This is then repeated at different frequencies (output) VAC to generate a (output) piecemeal of PSRR. AC signal and Ripple is thegraph amplitude of output signal. This is then repeated at different frequencies 这一方法可以与上一节所描述的结构一起使用。然而由于示波器的分辨率和灵敏度有限，这一方法仅仅对具有更低 of VAC to generate a piecemeal graph of PSRR. of VAC to LDO generate a piecemeal graph of PSRR. 值的 适用。由于大多数示波器可以测量到毫伏的范围，因此使用示波器可实际测量到的 的最大范围约 PSRRmethod This can be used along with the set-ups described in the previous section. PSRR But this method is only Thisgood method can be used along with the set-ups described in the previous section. But this method is only for LDOs with values to resolution and sensitivity of section. oscilloscopes. Since most This method can belower used PSRR along with thedue set-ups described in the previous But this method is only 为 40dB–50dB 。 good for LDOs with lower PSRR values due to resolution and sensitivity of oscilloscopes. Since most oscilloscopes can measure down to the millivolt range, the maximum range of PSRR that could good for LDOs with lower PSRR values due to resolution and sensitivity of oscilloscopes. Since most oscilloscopes can measure down toanthe millivolt range, the the maximum range of PSRR thatthat could realistically be can measured using oscilloscope isrange, about 40dB–50dB. oscilloscopes measure down to the millivolt maximum range of PSRR could realistically be measured using an oscilloscope is about 40dB–50dB. realistically be measured using an oscilloscope is about 40dB–50dB. SLAA414 – July 2009 年 7 Feedback 月 SLAA414 – July 2009 ZHCA089 2009 Submit Documentation SLAA414 ––July 2009 Submit Documentation Feedback 提交文档反馈 Submit Documentation Feedback LDO PSRR Measurement Simplified 测量简化说明 LDO PSRR LDOLDO PSRR Measurement Simplified PSRR Measurement Simplified 3 33 3 的PSRR测量 Measuring PSRR Using Oscilloscope LDO www.ti.com www.ti.com Using the TPS78101EVM from Texas Instruments, the PSRR is measured using signal generator 在德州仪器的 进行测量。输入与输出波形如图 TPS78101 评估板上，使用信号发生器和示波器对 PSRR 5 所示。 oscilloscope. The input and output waveforms are as shown in Figure 5: 测试条件如下： Test conditions and are: a. = 3V a.Vout Vout = 3V b. b.Iload Iload==150mA 150mA 时= c. VAC 1V (p-p) c.1kHz VAC 1V= (p-p) at 1kHz d.VDC VDC = 4.3V d. = 4.3V dc dc 图and 的输入及输出波形 Figure 5. Input Output Waveforms Measuring PSRR Using Oscilloscope 5. 用示波器测量 PSRRfor 由图 中的波形可计算得到 PSRR： And5the PSRR is calculated from waveforms in Figure 5 is: Ripple(input) mV Ripple(input)==984 984 mV Ripple(output) Ripple(output) ==194 194mV mV ，这一结果与 PSRR= =2020 log10(Ripple(input) / Ripple(output) = log10(0.984/0.194) 20 log10(0.984/0.194) = 14.10dB which closely的数据表中规定的 matches the PSRR log10(Ripple(input)/ Ripple(output)) = )20 = 14.10dB TPS78101 PSRR specified in the datasheet of TPS78101. 相一致。 PSRR This application report LDO shows various methods to measure the时需要考虑的不同方面。 PSRR of an LDO and 本应用报告给出了测量一个 的 PSRR 的多种方法并解释了测量 PSRR different aspects which need to be considered while measuring PSRR. 44 LDO PSRR 测量简化说明 LDO PSRR Measurement Simplified also explains ZHCA089 – 2009 7月 SLAA414 – July年2009 提交文档反馈 Submit Documentation Feedback 5 ZHCA089 重要声明 德州仪器 (TI) 及其下属子公司有权在不事先通知的情况下，随时对所提供的产品和服务进行更正、修改、增强、改进或其它更改， 并有权随时中止提供任何产品和服务。 客户在下订单前应获取最新的相关信息，并验证这些信息是否完整且是最新的。 所有产品的 销售都遵循在订单确认时所提供的 TI 销售条款与条件。 TI 保证其所销售的硬件产品的性能符合 TI 标准保修的适用规范。 仅在 TI 保修的范围内，且 TI 认为有必要时才会使用测试或其它质 量控制技术。 除非政府做出了硬性规定，否则没有必要对每种产品的所有参数进行测试。 TI 对应用帮助或客户产品设计不承担任何义务。 客户应对其使用 TI 组件的产品和应用自行负责。 为尽量减小与客户产品和应用相关 的风险，客户应提供充分的设计与操作安全措施。 TI 不对任何 TI 专利权、版权、屏蔽作品权或其它与使用了 TI 产品或服务的组合设备、机器、流程相关的 TI 知识产权中授予的直接 或隐含权限作出任何保证或解释。 TI 所发布的与第三方产品或服务有关的信息，不能构成从 TI 获得使用这些产品或服务的许可、授 权、或认可。 使用此类信息可能需要获得第三方的专利权或其它知识产权方面的许可，或是 TI 的专利权或其它知识产权方面的许 可。 对于 TI 的数据手册或数据表，仅在没有对内容进行任何篡改且带有相关授权、条件、限制和声明的情况下才允许进行复制。 在复制 信息的过程中对内容的篡改属于非法的、欺诈性商业行为。 TI 对此类篡改过的文件不承担任何责任。 在转售 TI 产品或服务时，如果存在对产品或服务参数的虚假陈述，则会失去相关 TI 产品或服务的明示或暗示授权，且这是非法的、 欺诈性商业行为。 TI 对此类虚假陈述不承担任何责任。 可访问以下 URL 地址以获取有关其它 TI 产品和应用解决方案的信息： 产品 放大器 http://www.ti.com.cn/amplifiers 数据转换器 http://www.ti.com.cn/dataconverters DSP http://www.ti.com.cn/dsp 接口 http://www.ti.com.cn/interface 逻辑 http://www.ti.com.cn/logic 电源管理 http://www.ti.com.cn/power 微控制器 http://www.ti.com.cn/microcontrollers 应用 音频 http://www.ti.com.cn/audio 汽车 http://www.ti.com.cn/automotive 宽带 http://www.ti.com.cn/broadband 数字控制 http://www.ti.com.cn/control 光纤网络 http://www.ti.com.cn/opticalnetwork 安全 http://www.ti.com.cn/security 电话 http://www.ti.com.cn/telecom 视频与成像 http://www.ti.com.cn/video 无线 http://www.ti.com.cn/wireless 邮寄地址：Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright © 2006, Texas Instruments Incorporated