LMX2314 National Semiconductor Corporation, LMX2314 Datasheet
LMX2314
Related parts for LMX2314
LMX2314 Summary of contents
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... Enable Clock) Supply voltage can range from The LMX2314 and the LMX2315 feature very low current consumption typically The LMX2314 is available in a JEDEC 16-pin surface mount plastic package The LMX2315 is available in a TSSOP 20-pin surface mount plastic package ...
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... Connection Diagrams LMX2314 JEDEC 16-Lead (0 150 Wide) Small Outline Molded Package (M) Order Number LMX2314M or LMX2314MX See NS Package Number M16A Pin Descriptions Pin No Pin No Pin Name I O 2314 2315 2314 2315 1 1 OSC OSC O OUT ...
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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 0V ...
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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 Charge Pump Output Current Magnitude Variation vs Voltage (Note ...
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Typical Performance Characteristics Charge Pump Current vs D Voltage o Charge Pump Current Variation I TRI-STATE 11766 – 29 Charge Pump Current 11766 – 31 ...
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... Typical Performance Characteristics Input Sensitivity vs Frequency Input Sensitivity at Temperature e Variation LMX2314 Input Impedance vs Frequency 100 MHz to 1 600 MHz Marker 1 500 MHz Real 67 Imag 317 Marker 2 900 MHz Real 24 Imag 150 ...
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Charge Pump Current Specification Definitions sink current sink current sink current at V ...
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Functional Description The simplified block diagram below shows the 19-bit data register the 14-bit R Counter and the S 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 (2315 only) 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 ...
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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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Application Information (Continued) Consider the following application example Example MHz V VCO (Note 900 MHz opt e F 200 kHz ref 4500 opt ref ...
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Application Information (Continued) MEASUREMENT RESULTS FIGURE 5 PLL Reference Spurs k b The reference spurious level is 74 dBc due to the loop filter attenuation and the low spurious noise level of the LMX2315 FIGURE 6 PLL Phase Noise 10 ...
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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 LMX2314 2315 frequency synthesizers These logic signals are converted into current pulses using the circuitry shown in Figure 9 to enable either charging or discharging ...
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... Physical Dimensions inches (millimeters) JEDEC 16-Lead (0 150 Wide) Small Outline Molded Package (M) For Tape and Reel Order Number LMX2314MX (2500 Units per Reel) Order Number LMX2314M NS Package Number M16A 19 ...
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Physical Dimensions millimeters (Continued) 20-Lead (0 173 Wide) Thin Shrink Small Outline Package (TM) For Tape and Reel Order Number LMX2315TMX (2500 Units per Reel) LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE ...