LMX2315TM National Semiconductor, LMX2315TM Datasheet
LMX2315TM
Specifications of LMX2315TM
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LMX2315TM Summary of contents
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... The LMX2315, LMX2320 and the LMX2325 are available in a TSSOP 20-pin surface mount plastic package. Block Diagram TRI-STATE ® registered trademark of National Semiconductor Corporation. MICROWIRE ™ and PLLatinum ™ are trademarks of National Semiconductor Corporation. © 2002 National Semiconductor Corporation Features n RF operation ...
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... Connection Diagram 20-Lead (0.173" Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2315TM, LMX2315TMX, LMX2325TM, LMX2325TMX, LMX2320TM or LMX2320TMX Pin Descriptions Pin No. Pin I/O Name 1 OSC I Oscillator input. A CMOS inverting gate input intended for connection to a crystal resonator for IN operation as an oscillator. The input has a V external CMOS or TTL logic gate ...
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Functional Block Diagram Note 1: The prescalar for the LMX2315 and LMX2320 is either 64/65 or 128/129, while the prescalar for the LMX2325 is 32/33 or 64/65. Note 2: The power down function is gated by the charge pump 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. Power Supply Voltage Voltage on Any Pin with GND = Storage Temperature Range ( Lead Temperature (T ) (solder, 4 sec.) L Electrical Characteristics LMX2325 and LMX2320 3.0V; LMX2315 V ...
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Electrical Characteristics LMX2325 and LMX2320 3.0V; LMX2315 Symbol Parameter I vs Charge Pump Output Current Do-sink I Sink vs Source Mismatch Do-source (Note Charge Pump Output Current Do Magnitude ...
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Typical Performance Characteristics Charge Pump Current vs D Voltage o Charge Pump Current Variation I TRI-STATE vs D Voltage Do o www.national.com (Continued) Charge Pump Current vs D DS012339-40 Sink vs Source Mismatch vs D DS012339-8 Oscillator Input Sensitivity DS012339-5 ...
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Typical Performance Characteristics LMX2320/25 Input Sensitivity vs Frequency LMX2315 Input Sensitivity vs Frequency LMX2320/25 Input Sensitivity at Temperature Variation (Continued) LMX2320/25 Input Sensitivity vs Frequency DS012339-10 LMX2315 Input Sensitivity vs Frequency DS012339-41 LMX2320/25 Input Sensitivity at ...
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Typical Performance Characteristics LMX2315 Input Sensitivity at Temperature Variation LMX2315 Input Impedance vs Frequency V = 2.7V to 5.5V 100 MHz to 1,600 MHz CC IN Marker 1 = 500 MHz, Real = 69, ...
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Charge Pump Current Specification Definitions sink current − sink current sink current ...
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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 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 transferred ...
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Functional Description 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 symmetrical ...
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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 increases impedance so that VCO output power is provided to the load rather than the PLL. Typical values are 10 IN power level impedance ranges ...
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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 For the loop to be stable the unity gain point must occur before the phase reaches −180 degrees. We therefore want the phase margin maximum when the magnitude of the open loop gain equals ...
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Application Information Consider the following application examples: Example # MHz/V VCO (*) RF = 900 MHz opt F = 200 kHz ref 4500 opt ref = 2 ...
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Application Information MEASUREMENT RESULTS (Example # 1) FIGURE 5. PLL Reference Spurs < 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 ...
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Application Information Converting to standard component values gives the follow- ing filter values, which are shown in Figure 560 6 2700 ...
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Application Information FIGURE 11. PLL Phase Noise The phase noise level at 150 Hz offset is −81.1 dBc/Hz. The spurs at 60 and 180 Hz offset are due line noise from the power supply. FIGURE 12. PLL ...
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Application Information the transistors used, the V drop of p, and the V OL < r’s under 1 mA loads. ( p’s V 0.1V and ( r 0.1V). Knowing these parameters along with the desired current allow us ...
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... Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2315TM, LMX2320TM or LMX2325TM For Tape and Reel Order Number LMX2315TMX, LMX2320TMX or LMX2325TMX (2500 Units per Reel) LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION ...