LMX2485E EVAL National Semiconductor, LMX2485E EVAL Datasheet
LMX2485E EVAL
Specifications of LMX2485E EVAL
Related parts for LMX2485E EVAL
LMX2485E EVAL Summary of contents
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... LMX2485E Evaluation Board Instructions National Semiconductor Corporation Wireless Communications, RF Products Group 2900 Semiconductor Dr. Santa Clara, CA 95052-8090 LMX2485ESQFPEBI M/S A2-600 Rev 3.10.2006 ...
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ABLE OF ONTENTS G D ...............................................................................................................3 ENERAL ESCRIPTION ..........................................................................................................................3 OOP ILTER E H ......................................................................................................................4 VALUATION INTS RF PLL HASE OISE WITH IFFERENT RF PLL ...
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... The LMX2485E Evaluation Board simplifies evaluation of the LMX2485E 2.6 GHz/0.8 GHz PLLatinum™ dual frequency synthesizer. The primary function of this board is to evaluate the LMX2485E device performance at low RF input frequencies, which is 50 MHz. The board enables all performance measurements with no additional support circuitry. The evaluation board consists of a LMX2485E device VCO module and RF loop filters built with discrete components ...
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... MHz. Slew rates less than 100 V/µs could have an negative effect on the performance of the LMX2485E. The default state for the LMX2485E Evaluation board in these instructions are 2 dithering disabled and charge pump current set to 8X (0.76 mA). Also RF_P is set to 1 for a Prescaler value achieve low divide ratios while not violating minimum divide ratio specifications ...
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PLL Phase Noise with Different CP Currents ...
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PLL Phase Noise with different Delta Sigma Modulator Order ...
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PLL Phase Noise with different Dithering Settings ...
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PLL Fractional Spurs with Different CP Currents ...
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PLL Fractional Spurs with different Delta Sigma Modulator Order ...
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PLL Fractional Spurs with different Dithering Settings ...
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Impact of Large Fractional Denominator (FM=2, DITH=0) This column loads Reset Modulator before loading Fraction. Only column Reset Modulator is used before loading before FM =2. Fraction = 1/5 Fraction = 10/50 ...
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PLL Lock Time Positive lock time is 360 µs Negative lock time is 421 µs RF ...
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CodeLoader Settings ...
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VccRFVCO VccVCO POWER_VCO VccIFVCO C5 R5 VddIF2 ...
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... VISHAY CRCW0603222JRT1 20 1 VISHAY CRCW0603000ZRT1 21 5 Vishay CRCW0603103JRT1 22 5 Vishay CRCW0603123JRT1 23 1 National Semiconductor LMX2485ESQ 24 1 National Semiconductor LP3985IM5-3 VARIL VCO190-52U Bill of Materials Value Unit Size Voltage Tolerance First GND 10 mils 4 layer. 62 mils total thickness down Stand-Offs 2-Pin Shunt 4-Pin ...
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... Additional Features of the LMX2485E Evaluation Board HYBRID VCO FOOTPRINT Although the evaluation board is created to support a particular VCO, the footprint is flexible and designed such that other VCOs are easy to put on the board. To mount a smaller VCO on the board, scratch off the solder mask with the flat edge of a screwdriver and then put solder on the pads such that it covers the exposed copper ...