LMV221SDX National Semiconductor, LMV221SDX Datasheet
LMV221SDX
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LMV221SDX Summary of contents
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... The LMV221 power detector is offered in the small 2 2 0.8 mm LLP package. Typical Application (a) LMV221 with output RC Low Pass Filter © 2008 National Semiconductor Corporation Features ■ linear in dB power detection range ■ Output voltage range 0 ■ ...
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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. Supply Voltage V - GND DD RF Input Input power DC Voltage Enable Input Voltage V - 0.4V < ESD Tolerance (Note 2) Human Body Model Machine Model Charge Device Model ...
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Symbol Parameter I Output Leakage Current in OUT,SD Shutdown mode RF Detector Transfer V Maximum Output Voltage OUT,MAX P = −5 dBm IN (Note 8) V Minimum Output Voltage OUT,MIN (Pedestal) ΔV Pedestal Variation over OUT,MIN temperature ΔV Output Voltage ...
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Symbol Parameter Power Measurement Performance E Log Conformance Error LC (Note 8) ≤ ≤ −40 dBm P −10 dBm IN E Variation over Temperature VOT (Note 8) ≤ ≤ −40 dBm P −10 dBm IN E Measurement Error for a ...
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Symbol Parameter S Temperature Sensitivity T 25°C < T < 85°C, (Note −10 dBm IN P Maximum Input Power for MAX dB(Note Minimum Input Power for MIN ...
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... REF 6 OUT DAP GND Ordering Information Package Part Number LMV221SD LLP-6 LMV221SDX Block Diagram www.national.com 6-pin LLP Top View Positive Supply Voltage DD Power Ground The device is enabled for EN = High, and brought to a low-power shutdown mode for EN = Low. RF input signal to the detector, internally terminated with 50 Ω. ...
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Typical Performance Characteristics T = 25°C, measured on a limited number of samples. A Supply Current vs. Supply Voltage Output Voltage vs. RF input Power Log Intercept vs. Frequency Unless otherwise specified, V Supply Current vs. Enable Voltage 20173705 Log ...
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Mean Output Voltage and Log Conformance Error vs. RF Input Power at 50 MHz Mean Output Voltage and Log Conformance Error vs. RF Input Power at 1855 MHz Mean Output Voltage and Log Conformance Error vs. RF Input Power at ...
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Log Conformance Error (Mean ±3 sigma) vs. RF Input Power at 50 MHz Log Conformance Error (Mean ±3 sigma) vs. RF Input Power at 1855 MHz Log Conformance Error (Mean ±3 sigma) vs. RF Input Power at 3000 MHz Log ...
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Mean Temperature Drift Error vs. RF Input Power at 50 MHz Mean Temperature Drift Error vs. RF Input Power at 1855 MHz Mean Temperature Drift Error vs. RF Input Power at 3000 MHz www.national.com Mean Temperature Drift Error vs. RF ...
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Temperature Drift Error (Mean ±3 sigma) vs. RF Input Power at 50 MHz Temperature Drift Error (Mean ±3 sigma) vs. RF Input Power at 1855 MHz Temperature Drift Error (Mean ±3 sigma) vs. RF Input Power at 3000 MHz Temperature ...
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Error for 1 dB Input Power Step vs. RF Input Power at 50 MHz Error for 1 dB Input Power Step vs. RF Input Power at 1855 MHz Error for 1 dB Input Power Step vs. RF Input Power at ...
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Error for 10 dB Input Power Step vs. RF Input Power at 50 MHz 20173732 Error for 10 dB Input Power Step vs. RF Input Power at 1855 MHz 20173734 Error for 10 dB Input Power Step vs. RF Input ...
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Mean Temperature Sensitivity vs. RF Input Power at 50 MHz Mean Temperature Sensitivity vs. RF Input Power at 1855 MHz Mean Temperature Sensitivity vs. RF Input Power at 3000 MHz www.national.com Mean Temperature Sensitivity vs. RF Input Power at 900 ...
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Temperature Sensitivity (Mean ±3 sigma) vs. RF Input Power at 50 MHz Temperature Sensitivity (Mean ±3 sigma) vs. RF Input Power at 1855 MHz Temperature Sensitivity (Mean ±3 sigma) vs. RF Input Power at 3000 MHz Temperature Sensitivity (Mean ±3 ...
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Output Voltage and Log Conformance Error vs. RF Input Power for various modulation types at 900 MHz RF Input Impedance vs. Frequency (Resistance & Reactance) Power Supply Rejection Ratio vs. Frequency www.national.com Output Voltage and Log Conformance Error vs. RF ...
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Sourcing Output Current vs. Output Voltage Output Voltage vs. Sourcing Current Sinking Output Current vs. Output Voltage 20173709 Output Voltage vs. Sinking Current 20173711 17 20173710 20173706 www.national.com ...
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Application Notes The LMV221 is a versatile logarithmic RF power detector suitable for use in power measurement systems. The LMV221 is particularly well suited for CDMA and UMTS ap- plications. It produces a DC voltage that is a measure for ...
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FIGURE 1. Convex Detector Transfer Function (a) and Linear Transfer Function (b) Figure 1 shows two different representations of the detector transfer function. In both graphs the input power along the horizontal axis is displayed in dBm, since most ...
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The advantages and disadvantages can be summarized as follows: • The temperature stability of (R)MS detectors is almost ...
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This can be accomplished by using two LMV221 RF power detectors according to Figure 4. A directional coupler is used to separate the forward and reflected power waves on the transmission line between the PA and the antenna. One ...
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Values for the parameters in this formula. The values for the parameters in the model can be obtained in various ways. They can be based on measurements of the detector transfer function in a precisely controlled environ- ment (parameter ...
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Unfortunately, the (numeric) inverse of the detector transfer function at different temperatures makes this expression rather impractical. However, since the drift error is usually small V (T) is only slightly different from V OUT means that we can apply the ...
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FIGURE 8. Elimination of the Systematic Component from the Temperature Drift The mean drift error represents the reproducible - systematic - part of the error, while the mean ± 3 sigma limits represent the combined systematic plus random error component. ...
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In a practical power measurement system, temperature com- pensation is usually only applied to a small power range around the maximum power level for two reasons: • The various communication standards require the highest accuracy in this range to limit ...
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Forcing a voltage to the enable input that is 400 mV higher than V or 400 mV lower than GND will damage DD the device and further ...
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The differential topology has the advantage that it is compen- sated for temperature drift of the internal reference voltage. This can be explained by looking at the transimpedance am- plifier of the LMV221 (Figure 13). FIGURE 13. Output Stage of ...
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Low frequency supply voltage variations due to PA switching might result in a ripple at the output voltage. The LMV221 has a Power Supply Rejection Ration for low frequencies. 4.1.2 Ground (GND) The LMV221 needs a ground ...
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W and the distance S. In order to minimize reflec- tions, the width W of the center trace should match the size of the package pad. The required value for the characteristic impedance can subsequently be realized by ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 6-Pin LLP NS Package Number SDB06A 30 ...
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Notes 31 www.national.com ...
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