LMX25311778EVAL National Semiconductor, LMX25311778EVAL Datasheet
LMX25311778EVAL
Specifications of LMX25311778EVAL
LMX25311778EVAL Summary of contents
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... Automotive ■ CATV Equipment ■ Instrumentation and Test Equipment ■ RFID Readers © 2008 National Semiconductor Corporation Features ■ Multiple Frequency Options Available — See Selection Guide Below — Frequencies from: 553 MHz - 2790 MHz ■ PLL Features — Fractional-N Delta Sigma Modulator Order programmable up to 4th order — ...
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Functional Block Diagram www.national.com 2 20101101 ...
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Connection Diagrams 36-Pin LLP (LQ) Package, D Version (LMX2531LQ1146E/1226E/1312E/1415E/1515E) 36-Pin LLP (LQ) Package, A Version (All Other Versions) 3 20101104 20101102 www.national.com ...
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Pin Descriptions Pin # Pin Name I/O Power Supply for digital LDO circuitry. Input may range from 2.8 - 3.2 V. Bypass capacitors should be 1 VccDIG - placed as close as possible to this pin and ground. 3 GND ...
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Connection Diagram Pin(s) These pins are inputs to voltage regulators. Because the LMX2531 contains internal regulators, the power supply VccDIG noise rejection is very good and capacitors at this pin are not critical filter can be used to ...
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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. Parameter Power Supply Voltage Storage Temperature Range Lead Temperature (solder 4 sec.) Recommended Operating Conditions Parameter Power Supply Voltage (VccDig, VccVCO, VccBUF) ...
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Electrical Characteristics Symbol Parameter Power Supply Current Power I CC Supply Current I PD Power Down Current CC I OSC Oscillator Input High Current IH I OSC Oscillator Input Low Current IL f Frequency Range OSCin v Oscillator Sensitivity OSCin ...
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Symbol Parameter Operating Frequency Range (All options have a frequency f divider, this applies before the Fout divider. The frequency after the divider is half of what is shown) www.national.com Conditions VCO Frequencies LMX2531LQ1146E LMX2531LQ1226E LMX2531LQ1312E LMX2531LQ1415E LMX2531LQ1515E LMX2531LQ1570E LMX2531LQ1650E ...
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Symbol Parameter Maximum Allowable Temperature Drift for ΔT CL Continuous Lock (Note 4) Output Power Ω Load p (Applies across entire tuning Fout range.) Fine Tuning Sensitivity (When a range is displayed in the typical column, indicates ...
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Symbol Parameter Harmonic Suppression HS (Applies Across Entire Tuning Fout Range) PUSH Frequency Pushing Fout PULL Frequency Pulling Fout Z Output Impedance Fout www.national.com Conditions LMX2531LQ1146E /1226E/1312E Divider /1415E/1515E Disabled All Other Options 2nd Harmonic 50 Ω Load LMX2531LQ1146E /1226E/1312E ...
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Symbol Parameter Phase Noise L(f) Fout (LMX2531LQ1146E) Phase Noise L(f) Fout (LMX2531LQ1226E) Phase Noise L(f) Fout (LMX2531LQ1312E) Phase Noise L(f) Fout (LMX2531LQ1415E) Phase Noise L(f) Fout (LMX2531LQ1515E) Phase Noise L(f) Fout (LMX2531LQ1570E) Conditions VCO Phase Noise (Note 5) 10 kHz ...
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Symbol Parameter Phase Noise L(f) Fout (LMX2531LQ1650E) Phase Noise L(f) Fout (LMX2531LQ1700E) Phase Noise L(f) Fout (LMX2531LQ1742) Phase Noise L(f) Fout (LMX2531LQ1778E) Phase Noise L(f) Fout (LMX2531LQ1910E) Phase Noise L(f) Fout (LMX2531LQ2080E) www.national.com Conditions 10 kHz Offset 100 kHz Offset ...
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Symbol Parameter Phase Noise L(f) Fout (LMX2531LQ2265E) Phase Noise L(f) Fout (LMX2531LQ2570E) Conditions 10 kHz Offset 100 kHz Offset f = 2264 MHz Fout DIV2 = 0 1 MHz Offset 5 MHz Offset 10 kHz Offset 100 kHz Offset f ...
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Symbol Parameter V High-Level Input Voltage IH V Low-Level Input Voltage IL I High-Level Input Current IH I Low-Level Input Current IL V High-Level Output Voltage OH V Low-Level Output Voltage OL t Data to Clock Set Up Time CS ...
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Serial Data Timing Diagram The DATA is clocked into a shift register on each rising edge of the CLK signal. On the rising edge of the LE signal, the data is sent from the shift registers to an actual counter. ...
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Typical Performance Characteristics Frequency (MHz) Real 1 4.98 5 3.44 10 1.42 20 0.52 30 0.29 40 0.18 50 0.13 60 0.10 70 0.09 80 0.07 90 0.07 100 0.06 110 0.06 120 0.05 130 0.05 140 0.04 150 0.04 ...
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Functional Description The LMX2531 is a low power, high performance frequency synthesizer system which includes the PLL, VCO, and par- tially integrated loop filter. The following sections give a dis- cussion of the various blocks of this device. 1.1 ...
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... For de- sign tools and more information on partially integrated loop filters www.national.com/wireless. 1.6 LOW NOISE, FULLY INTEGRATED VCO The LMX2531 includes a fully integrated VCO, including the inductors ...
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General Programming Information The LMX2531 is programmed using 11 24-bit registers used to control the LMX2531 operation. A 24-bit shift register is used as a temporary register to indirectly program the on-chip registers. The shift register consists of a ...
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EN_PLL EN_VCO EN_OSC EN_VCOLD EN_PLLLDO1 EN_PLLLDO2 EN_DIGLDO EN_LPFLTR REG_RST 20 ...
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REGISTER R0 The action of programming the R0 register activates a frequency calibration routine for the VCO. This calibration is necessary to get the VCO to center the tuning voltage for optimal performance. If the temperature drifts considerably, then ...
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REGISTER R1 2.2.1 NUM[21:12] These are the MSB bits in for the fractional numerator that already have been described. 2.2.2 N[10: MSB Bits for the N Counter These are the 2 MSB bits for the N counter, ...
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REGISTER R2 2.3.1 R[5: Counter Value These bits determine the phase detector frequency. The OSCin frequency is divided by this R counter value. Note that only the values 16, and 32 are ...
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REGISTER R3 2.4.1 DEN[21:12] -- Extension for the Fractional Denominator These are the MSB bits of the DEN word, which have already been discussed. 2.4.2 FoLD[3:0] -- Multiplexed Output for Ftest/LD Pin The FoLD[3:0] word is used to program ...
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DITHER -- Dithering Dithering is useful in reducing fractional spurs, especially those that occur a a fraction of the channel spacing. The only exception is when the fractional numerator is zero. In this case, dithering usually is not a ...
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REGISTER R4 2.5.1 TOC[13:0] -- Time Out Counter for FastLock When the value of this word less, then FastLock is disabled, and this pin can only be used for general purpose I/O. When this value is ...
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REGISTER R5 2.6.1 EN_PLL -- Enable Bit for PLL When this bit is set to 1 (default), the PLL is powered up, otherwise powered down. 2.6.2 EN_VCO -- Enable Bit for the VCO When this bit is ...
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REGISTER R6 2.7.1 C3_C4_ADJ[2:0] -- VALUE FOR C3 AND C4 IN THE INTERNAL LOOP FILTER C3_C4_ADJ 2.7.2 R3_ADJ_FL[1:0] -- Value for Internal Loop Filter Resistor R3 During Fastlock R3_ADJ_FL Value 2.7.3 ...
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VCO_ACI_SEL This bit is used to optimize the VCO phase noise. The recommended values are what are used for all testing purposes, and this bit should be set as the table below instructs. Part All Other Options LMX2531LQ2265E LMX2531LQ2570E ...
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REGISTER R7 2.8.1 XTLDIV[1:0] -- Division Ratio for the Crystal Frequency The frequency provided to the VCO frequency calibration circuitry is based on the OSCin frequency divided down by a factor, determined by the XTLDIV word. Note that this ...
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REGISTER R8 2.9.1 XTLMAN2 -- MANUAL CRYSTAL MODE SECOND ADJUSTMENT This bit also adjusts the calibration timing for lock time. In the case that manual mode for XTLSEL is selected and the OSCin frequency is greater than 40 MHz, ...
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Physical Dimensions Leadless Leadframe Package (NS Package Number LQA036D), D Version (Bottom View) Leadless Leadframe Package (NS Package Number LQA036A), A Version (Bottom View) www.national.com inches (millimeters) unless otherwise noted (LMX2531LQ1146E/1226E/1312E/1415E/1515E) Order Number LMX2531LQX for 2500 Unit Reel Order Number ...
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Part Marking LMX2531LQ1146E 311146E LMX2531LQ1226E 311226E LMX2531LQ1312E 311312E LMX2531LQ1415E 311415E LMX2531LQ1515E 311515E LMX2531LQ1570E 311570EB LMX2531LQ1650E 311650EA Part Package LMX2531LQ1700E LQA036D LMX2531LQ1742 LQA036D LMX2531LQ1778E LQA036D LMX2531LQ1910E LQA036D LMX2531LQ2080E LQA036D LMX2531LQ2265E LQA036A LMX2531LQ2570E LQA036A 33 Marking Package 311778EB LQA036A 311742EA LQA036A 311778EA ...
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... For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock and Timing www.national.com/timing Data Converters www.national.com/adc Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www.national.com/ldo LED Lighting www ...