LMX2305TM National Semiconductor, LMX2305TM Datasheet
LMX2305TM
Specifications of LMX2305TM
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LMX2305TM Summary of contents
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... The LMX2305 features very low current consumption typically 75V The LMX2305 is available in a TSSOP 20-pin surface mount plastic package Block Diagram TRI-STATE is a registered trademark of National Semiconductor Corporation MICROWIRE TM and PLLatinum TM are trademarks of National Semiconductor Corporation ...
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... Output for external charge pump connect http www national com LMX2305 20-Lead (0 173 Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2305TM or LMX2305TMX See NS Package Number MTC20 Description 2 input threshold and can be driven from open drain N-channel transistor and requires a pull-up ...
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Functional Block Diagram Note 1 The power down function is gated by the charge pump to prevent any unwanted frequency jumps Once the power down pin is brought low the part will go into power down mode when the charge ...
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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 Power Supply Voltage Voltage on Any Pin with GND Storage Temperature Range ( Lead Temperature (T ) (solder 4 sec ) L Electrical Characteristics Symbol Parameter I Power Supply Current ...
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Electrical Characteristics Symbol Parameter I Charge Pump Output Current D o -source -sink I Charge Pump TRI-STATE Current D o -Tri V High-Level Output Voltage OH V Low-Level Output Voltage OL V High-Level Output Voltage (OSC OH ...
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Functional Description The simplified block diagram below shows the 19-bit data register the 14-bit R Counter and the R15 Latch and the 18-bit N Counter (intermediate latches are not shown) The data stream is clocked (on the rising edge) into ...
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Functional Description (Continued) PROGRAMMABLE DIVIDER (N COUNTER) The N counter consists of the 7-bit swallow counter (A counter) and the 11-bit programmable counter (B counter) If the Control Bit (last bit shifted into the Data Register) is LOW data is ...
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Functional Description (Continued) SERIAL DATA INPUT TIMING Notes Parenthesis data indicates programmable reference divider data Data shifted into register on clock rising edge Data is shifted in MSB first Test Conditions The Serial Data Input Timing is tested using a ...
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Analog Switch The analog switch is useful for radio systems that utilize a frequency scanning mode and a narrow band mode The purpose of the analog switch is to decrease the loop filter time constant allowing the VCO to adjust ...
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Typical Application Example Operational Notes VCO is assumed AC coupled R increases impedance so that VCO output power is provided to the load rather than the PLL Typical values are 10 IN level f RF impedance ranges from 40 to ...
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Application Information LOOP FILTER DESIGN A block diagram of the basic phase locked loop is shown FIGURE 1 Basic Charge Pump Phase Locked Loop An example of a passive loop filter configuration including the transfer function of the loop filter ...
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Application Information (Continued) Therefore if we specify the loop bandwidth phase margin Equations 1 through 6 allow us to calcu- p late the two time constants T1 and T2 as shown in equa- tions 7 and 8 A common rule ...
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Application Information (Continued) EXTERNAL CHARGE PUMP The LMX PLLatinum series of frequency synthesizers are equipped with an internal balanced charge pump as well as outputs for driving an external charge pump Although the superior performance of NSC’s on board charge ...
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... Physical Dimensions inches (millimeters) unless otherwise noted 20-Lead (0 173 Wide) Thin Shrink Small Outline Package (TM) For Tape and Reel Order Number LMX2305TMX (2500 Units per Reel) LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT ...