LMX2346 National Semiconductor Corporation, LMX2346 Datasheet
LMX2346
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LMX2346 Summary of contents
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... General Description The LMX2346/7 are high performance frequency synthesiz- ers with an integrated 32/33 dual modulus prescaler. The LMX2346 is designed for RF operation up to 2.0 GHz. The LMX2347 is designed for RF operation up to 2.5 GHz. Using a proprietary digital phase locked loop technique, the LMX2346/7 generates very stable, low noise control signals for UHF and VHF voltage controlled oscillators ...
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Connection Diagrams 16-Pin Chip Scale Package NS Package Number SLB16A Pin Descriptions Pin Number Pin Name 16-Pin 16-Pin CSP TSSOP OSC GND 4 6 www.national.com ...
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... I/O Description I RF prescaler complementary input. For single ended operation, this pin should be AC grounded. The LMX2346/7 can be driven differentially when a bypass capacitor is omitted PLL prescaler input. Small signal input from the VCO. I High impedance CMOS Clock input. Data is clocked in on the rising edge, into the 18-bit shift register ...
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Pin Descriptions (Continued) Pin Number Pin Name 16-Pin 16-Pin CSP TSSOP 12, 14, 2, 13, 15 www.national.com I/O Description O Locked Detect output. Multi-function CMOS output pin that provides multiplexed access to digital ...
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... P i Storage Temperature Range Electrical Characteristics The following conditions apply 3.0V Symbol Parameter Power Supply Current, LMX2346 CC Power Supply Current, LMX2347 I -pwdn Power Down Current CC RF PRESCALER F Operating Frequency Prescaler, LMX2346 Operating Frequency, RF Prescaler, LMX2347 PF Input Sensitivity, RF Prescaler ...
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Electrical Characteristics The following conditions apply Symbol Parameter LOGICAL INTERFACE (CE, CLOCK, LE, DATA, LD) 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 ...
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... Typical Performance Characteristics LMX2346 TRI-STATE vs CP Voltage at 85˚ 20038422 20038423 www.national.com ...
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... Typical Performance Characteristics (See forumla under Charge Pump Current Specifications Definitions) www.national.com (Continued) LMX2346/7 Charge Pump Sweeps Sink vs Source Mismatch 8 20038424 20038425 ...
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... Typical Performance Characteristics (See forumla under Charge Pump Current Specifications Definitions) (Continued) Charge Pump Current Variation LMX2346 F Sensitivity vs Frequency at 3. 20038426 20038427 www.national.com ...
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... Typical Performance Characteristics www.national.com (Continued) LMX2346 F Sensitivity vs Frequency at 5.5V IN LMX2347 F Sensitivity vs Frequency at 3. 20038428 20038429 ...
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... Typical Performance Characteristics LMX2346/7 OSC (Continued) LMX2347 F Sensitivity vs Frequency at 5.5V IN Sensitivity vs Frequency at 3. 20038430 20038431 www.national.com ...
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... Typical Performance Characteristics LMX2346 F Input Impedance IN www.national.com (Continued) LMX2346/7 OSC Sensitivity vs Frequency at 5.5V IN 20038433 12 20038432 LMX2347 F Input Impedance IN 20038434 ...
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... LMX2346/7SLB F IMPEDANCE IN = 25˚ POWERED-DOWN POWERED-UP Real Imaginary Real | (Ω) (Ω) (Ω) (Ω) 490 −292 570 510 365 −257 446 ...
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... Typical Performance Characteristics LMX2346/7SLB OSC LMX2346/7SLB OSC www.national.com Input Impedance vs Frequency (R_OPT set MHz) IN Input Impedance vs Frequency (R_OPT= 7or set 104MHz 20038435 20038436 ...
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... LMX2346/7SLB OSC IN LMX2346/7SLB OSC OSC BUFFER IN NORMAL OPERATION Imag- Real F inary |ZOSC | OSC IN ZOSC IN (MHz) ZOSC (Ω) IN (Ω) (Ω) 5 1100 −4800 4920 10 340 −2200 2230 15 170 −1600 1610 20 120 −1120 1130 25 85 −953 957 30 75 −800 804 35 68 −692 695 ...
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... LMX2346/7SLB OSC IN LMX2346/7SLB OSC OSC BUFFER IN NORMAL OPERATION Imag- Real F inary |ZOSC | OSC IN ZOSC IN (MHz) ZOSC (Ω) IN (Ω) (Ω) 5 1500 −5750 5940 10 390 −2700 2730 15 190 −2010 2020 20 110 −1510 1510 25 83 −1210 1210 30 62 −972 974 35 53 −842 844 ...
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Charge Pump Current Specification Definitions − ∆ Charge Pump Sink Current at VCP = Charge Pump Sink Current at VCP = ∆ Charge Pump Sink Current ...
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Serial Data Input Timing Notes: 1. Data is shifted into register on clock rising edge. 2. Data is shifted in MSB first. F Sensitivity Test Setup IN Notes: 1. Test Conditions: NA_CNTR = 16, NB_CNTR = 312, LD_OUT = 3, ...
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... Functional Description The basic phase-lock-loop (PLL) configuration consists of a high-stability crystal reference oscillator, a frequency synthe- sizer such as the National Semiconductor LMX2346/7, a voltage controlled oscillator (VCO), and a passive loop filter. The frequency synthesizer includes a phase detector, cur- rent mode charge pump, a programmable reference divider, and a programmable feedback divider ...
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... Refer to Section 2.2.1 for details on programming the R Counter. 1.3 RF PRESCALER The LMX2346/7 contain a fixed 32/33 dual modulus RF prescaler. The RF Prescaler operates from 100 MHz to 2000 MHz on the LMX2346 and from 100 MHz to 2500 MHz on the LMX2347. The complementary F and F input pins drive the input of ...
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... A complete programming description is provided in Section 2.0. 1.8 MULTI-FUNCTION OUTPUT The LMX2346/7 LD pin is a multi-function output that can be configured as a digital lock detect, an analog lock detect, as well as monitor the output of the reference divider, or feed- back divider circuits. The LD_OUT control word is used to select the desired output function ...
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... Counter Reset 1 3 Power-down (Asynchronous) The LMX2346/7 are power controlled through logical control of the CE pin in conjunction with programming of the PD control word. A truth table is provided that describes how the state of the CE pin and the PD control word set the operating mode of the device. A complete programming description for the PD control word is provided in Section 2 ...
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Programming Description 2.2.1 R_CTR[9:0] Reference Divider (R COUNTER) The reference divider can be programmed to support divide ratios from 2 to 1023. Divide ratios of less than 2 are prohibited. Reference Divider Ratio • ...
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Programming Description 2.2.5 R_OPT[2:0] Reference Oscillator Optimization The R_OPT control words are used to optimize the performance of the reference buffer circuit for best Phase Noise and power consumption performance based on the frequency of the reference source. 2.3 ...
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... Order Information Order Number LMX2346TM LMX2346TMX LMX2346SLBX LMX2347TM LMX2347TMX LMX2347SLBX Package Type Packing Information TSSOP-16 94 Units per rail carrier MTC16 TSSOP-16 2500 Units, Tape & Reel MTC16 CSP-16 2500 Units, Tape & Reel SLB16A TSSOP-16 94 Units per rail carrier MTC16 TSSOP-16 2500 Units, Tape & ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 16-Pin Thin Shrink Small Outline Package Order Number LMX2346TM, LMX2346TMX NS Package Number MTC16 26 ...
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... Chip Scale Package Order Number LMX2346SLB or LMX2347SLB For Tape and Reel (2500 Units Per Reel) Order Number LMX2346SLBX or LMX2347SLBX NS Package Number SLB16A 2. A critical component is any component of a life support device or system whose failure to perform ...