LMX2301 National Semiconductor Corporation, LMX2301 Datasheet
LMX2301
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LMX2301 Summary of contents
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... Serial data is transferred into the LMX2301 via a three line MICROWIRE interface (Data Enable Clock) Supply volt- TM ...
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... NC No connect http www national com LMX2301 20-Lead (0 173 Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2301TM or LMX2301TMX 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 e b with GND ...
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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 11-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 11-bit programmable counter If the Control Bit (last bit shifted into the Data Register) is LOW data is transferred from the 19-bit shift register into an 11-bit ...
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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 10X to 200X depending on the VCO power IN level ...
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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 w 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 ...
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... One possible architecture for an external charge pump cur- rent source is shown in Figure 9 The signals w the diagram correspond to the phase detector outputs of the LMX2301 frequency synthesizer These logic signals are converted into current pulses using the circuitry shown in Figure 9 to enable either charging or discharging of the ...
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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 LMX2301TMX (2500 Units per Reel) LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT ...