LMH6555EVAL National Semiconductor, LMH6555EVAL Datasheet
LMH6555EVAL
Specifications of LMH6555EVAL
LMH6555EVAL Summary of contents
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... ADC081000/ ADC081500 (single or dual ADC), the LMH6555 forms an excellent 8-bit data acquisition system with analog bandwidths exceeding 750 MHz. The LMH6555 is offered in a space saving 16-pin LLP pack- age. Typical Application © 2007 National Semiconductor Corporation Features Typical values unless otherwise specified. ■ −3 dB bandwidth (V ■ ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Tolerance (Note 5) Human Body Model Machine Model V S Output Short Circuit Duration (one pin to ground) Common Mode Input Voltage 3.3V Electrical Characteristics ...
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Symbol Parameter OIP3 Output 3 rd Order Intermodulation Intercept OIM3 3 rd Order Intermodulation Distortion e Output Referred Voltage Noise no NF Noise Figure Input Characteristics R CM Input Resistance IN R Differential Input Resistance IN_DIFF C Input Capacitance IN ...
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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, see the Electrical ...
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Definition of Terms and Specifications (Alphabetical Order) Unless otherwise specified, V CM_REF 1. A (dB) Change in the differential output voltage (ΔV V_CM voltage (ΔV Insertion gain from a single ended 50Ω (or 100Ω differential) source to the differential output ...
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Typical Performance Characteristics = 100Ω differential 0 OUT the datasheet. Frequency Response Linear Phase Deviation & Group Delay −1 dB Compression vs. Frequency www.national.com Unless otherwise specified See the Definition of Terms and ...
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Step Response Settling Time 20127771 3 rd Order Intermodulation Distortion 20127770 Insertion Gain Distribution 20127768 Harmonic Distortion vs. Frequency A & R vs. V V_DIFF IN_DIFF Insertion Gain Variation vs. Input Amplitude 7 20127742 I_CM 20127761 20127774 www.national.com ...
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PSRR & PSRR_CM vs. Frequency CMRR vs. Frequency S_Parameters vs. Frequency www.national.com CMRR vs. V 20127756 Noise Density & Noise Figure 20127754 Differential Output Offset Variation for 3 Representative Units 20127763 8 I_CM 20127775 20127755 20127766 ...
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Common Mode Offset Voltage Variation vs. V Supply Current vs. Temperature CM_REF 20127767 9 20127769 www.national.com ...
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Application Information See the Definition of Terms and Conditions section for defi- nition of terms used. GENERAL The LMH6555 consists of three individual amplifiers: The V driver, V driver, and the common mode amplifier. OUT + OUT − Being a ...
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CIRCUIT ANALYSIS Figure 2 shows the block diagram of the LMH6555. = 39Ω 25Ω 430Ω ...
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SINGLE-ENDED INPUT The following is the procedure for determining the device op- erating conditions for single ended input applications. This example will use the schematic shown in Figure 3. FIGURE 3. Single-Ended Input Drive 1. Determine the driven input’s (V ...
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DIFFERENTIAL INPUT The following is the procedure for determining the device op- erating conditions for differential input applications using the Figure 5 schematic as an example. Assuming transformer secondary 300 mV IN FIGURE 5. Differential Input Drive ...
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FIGURE 7. Gain & Output Offset Voltage vs. Source Impedance Shift for Single Ended Input Drive As can be seen in Figure 7, the source impedance of the input side being driven has a bigger effect on gain than the ...
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FIGURE 10. LMH6555 Differential Output Shift Due Figure 9 To shift the LMH6555 differential output negative by about 100 mV, referring to the plot in Figure 10 around 3.9 kΩ in the schematic of ...
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For applications similar to the one shown in Figure 12, the following conditions should be maintained: 1. The LMH6555 differential output voltage has to comply with the ADC full scale voltage (800 mV 2. The LMH6555 input Common Mode Voltage ...
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... R IN_DIFF So, for the component values shown (C = 523Ω): = R S2 f_cut-off = 28.2 kHz DATA ACQUISITION APPLICATIONS Figure 17 shows the LMH6555 used as the differential driver to the National Semiconductor ADC081500 running at 1.5G samples/second. 20127750 FIGURE 17. Schematic of the LMH6555 Interfaced to the ) = 1.88 mA (based (differential) /2 ...
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In the schematic of Figure 17, the LMH6555 converts a single ended input into a differential output for direct interface to the ADC's 100Ω differential input. An alternative approach to us- ing the LMH6555 for this purpose, would have been ...
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... The evaluation board can be ordered when a device sample request is placed with National Semiconductor. 19 LMH6555 Driver Single/ Speed (bits) Dual (MSPS 500 8 S 1000 8 D 1000 8 D 1000 8 S 1500 8 D 1500 8 D 1500 8 S 3000 8 S 3000 Package Evaluation Board Ordering ID 16-Pin LLP LMH6555EVAL www.national.com ...
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Appendix Here is a more detailed analysis of the LMH6555, including the derivation of the expressions used throughout the Appli- cation Information. INPUT STAGE Because of the input stage cross-coupling, if the instanta- neous values of the input node voltages ...
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Using the calculated swing on V with known estimate the input impedance follows: IN Differential Input Analysis Assume that the LMH6555 is used as a differential amplifier with a transformer with its Center Tap at ...
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With an output differential load 100Ω, half the differ- L ential swing between the output emitters appears at the LMH6555 output terminals OUT With good matching between the input source impedances, R and R ...
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Physical Dimensions inches (millimeters) unless otherwise noted 16-Pin LLP NS Package Number SQA16A 23 www.national.com ...
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