LMX2542LQ2121 NSC [National Semiconductor], LMX2542LQ2121 Datasheet
LMX2542LQ2121
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LMX2542LQ2121 Summary of contents
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LMX2542 TM PLLatinum Cellular and GPS Frequency Synthesizer System with Integrated VCO General Description LMX2542 is a highly integrated, high performance, low power frequency synthesizer system optimized for Cellular- CDMA 1xRTT and IS-95 mobile handsets and data systems with GPS ...
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Functional Block Diagram www.national.com 2 20082401 ...
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Connection Diagram Note: Analog GND connected through exposed die attached pad. Pin Description Pin No. Pin Name I/O 1 Fin — CPout — CLK I 7 DATA I ...
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Pin Description (Continued) Pin No. Pin Name I — — GND — 22 OSCin — GND — 25 GND — ...
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... Ordering Information Model RF Min Frequency (MHz) LMX2542LQX2121 2087.73 LMX2542LQ2121 2087.73 Part Number Description RF Max RF Center Frequency Frequency Frequency (MHz) (MHz) (MHz) ~ 2121 2155.14 367.20 ~ 2121 2155.14 367. Package Packing Marking 25422121 4500 Units on Tape and Reel 25422121 1000 Units on Tape ...
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Absolute Maximum Ratings 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Power Supply Voltage V to GND GND DD Voltage on any pin to GND (V ...
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Electrical Characteristics 2.8V +25˚C, unless otherwise specified Symbol Parameter RF VCO SPURS RF Synthesizer Reference Spurs VCO Harmonic Suppression RF t Channel Switch Lock Time RFLOCK ...
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Electrical Characteristics 2.8V +25˚C, unless otherwise specified Symbol Parameter DIGITAL INTERFACE (CE, DATA, CLK, LE, LD) V High-Level Input Voltage IH V Low-Level Input Voltage IL I High-Level Input ...
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Typical Performance Characteristics RF VCO Output Impedance 2.8V RFout R jX Ω Ω (MHz) 2087.73 26.406 −34.650 2105.28 25.385 −30.800 2121.00 23.898 −28.122 2155.14 19.979 −23.102 = 25˚C 20082412 |R + jX| ...
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Serial Data Input Timing Notes: 1. DATA is clocked into the 24-bit shift register on the rising edge of CLK. 2. The MSB of DATA is shifted in first. www.national.com 10 20082404 ...
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Functional Description LMX2542 is a highly integrated, high performance, low power, frequency synthesizer system optimized for Cellular- CDMA 1xRTT and IS-95 mobile handsets and data systems with GPS capabilities. Using a proprietary digital phase locked loop technique, LMX2542 generates ...
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Functional Description 1.2 VCO FREQUENCY TUNING The center frequency of the RF VCO is determined mainly by the resonant frequency of the tank circuit. This tank circuit is implemented on-chip and requires no external inductor. LMX2542 actively tunes the ...
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Functional Description 1.4 RF DIGITAL FILTERED LOCK DETECT A digital filtered lock detect status genrated from the RF phase frequency detector (PFD) is available on the LD pin (Pin 19) when the RF_LD bit (R0[21]) is set to 1. ...
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Functional Description 1.5 MICROWIRE SERIAL INTERFACE The programmable register set is accessed via the MI- CROWIRE serial interface. The interface comprises three signal pins: CLK, DATA, and LE. Serial data is clocked into the 24-bit shift register on the ...
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Programming Description 2.1 MICROWIRE INTERFACE The MICROWIRE Serial Port Interface (SPI) has a 24-bit shift register to store the incoming DATA bits temporarily. The incoming DATA is loaded into the shift register from MSB to LSB. The data is ...
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Programming Description 2.2 R0 REGISTER The R0 register contains the RF_FN, RF_A, RF_B, RF_LD, and SPI_DEF control words. The register address bits are R0[1:0] = 00. The detailed descriptions and programming information for each control word is discussed in ...
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Programming Description 2.2.3 RF_B[3: Synthesizer Programmable Binary Counter (B Counter) (R0[16:19]) The RF_B control word is used to setup the RF synthesizer’s B counter. The B counter is a 4-bit programmable binary counter used in the programmable ...
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Programming Description 2.3 R1 REGISTER The R1 register contains the FREQ_OFF, RF_EN and OB_CRL control words. The register address bits are R1[1:0] = 01. The detailed descriptions and programming information for each control word is discussed in the following ...
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Programming Description 2.4 R2 REGISTER The R2 register contains the IF_EN, IF_CUR, IF_FREQ, OSC_FREQ, and VCO_CUR control words. The register address bits are R2[1:0] = 10. The detailed descriptions and programming information for each control word is discussed in ...
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Programming Description 2.4.5 VCO_CUR[1: VCO Dynamic Current (R2[9:8]) The VCO_CUR control word is used to set the dynamic current for the RF VCO. A maximum dynamic current is recommended, and is achieved when VCO_CUR[1:0] word = 11. ...
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Programming Description 2.7 R5 REGISTER The R5 register contains the IF_R control word. The register address bits are R5[4:0] = 01111. Register R5 is active only when the SPI_DEF bit in Register R0 is set to 0. Regsiter R5 ...
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Physical Dimensions 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. ...