LMX2350 National Semiconductor Corporation, LMX2350 Datasheet
LMX2350
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LMX2350 Summary of contents
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... FastLock ™ mode. Serial data is transferred into the LMX2350/2352 via a three wire interface (Data, LE, Clock). Supply voltage can range from 2 5.5 V. The LMX2350/ Block Diagram © 2001 National Semiconductor Corporation LMX2352 family features very low current consumption; typi- cally LMX2350 (2.5 GHz) 6.5 mA, LMX2352 (1.2 GHz) 4. ...
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... OSCx I/O www.national.com DS100831-2 Order Number LMX2350TM or LMX2352TM NS Package Number MTC24 DS100831-22 Description Programmable CMOS output. Level of the output is controlled by IF_N [17] bit. RF PLL power supply voltage input. Must be equal to Vcc 5.5 V. Bypass capacitors should be placed as close as possible to this pin and be connected directly to the ground plane. ...
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Pin Descriptions (Continued) Pin No. Pin No. Pin Name I/O for CSP for Package TSSOP package 9 10 OSCin FoLD RF_EN IF_EN CLOCK DATA I ...
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... Conditions LMX2350 RF and IF 2.7V to 5.5V cc LMX2352 RF and IF 2.7V to 5.5V cc LMX2350/52 IF only 2.7V to 5.5V cc RF_EN = IF_EN = LOW LMX2350 Prescaler = 32 (Note 3) Prescaler = 16 (Note 3) LMX2352 Prescaler = 16 (Note 3) Prescaler = 8 (Note 3) No load on OSCx (Note 3) With resonator load on OSCx (Note 3) RF and IF 2.7V V 3.0V CC 3.0V V 5. 5.5V ...
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Electrical Characteristics specified) (Continued) All Min/Max specifications are guaranteeed by design, or test, or statistical methods. Symbol Parameter Charge Pump ICPo- RF Charge Pump source Output Current (see RF Programming ICPo- sink RF Description 3.2.2) ICPo- source RF ICPo- sink ...
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Charge Pump Current Specification Definitions sink current − sink current Vp sink current ...
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... RF Sensitivity Test Block Diagram Note 10,000 Note: Sensitivity limit is reached when the error of the divided RF output, F Typical Performance Characteristics LMX2350 I TRI-STATE vs CPO CP Voltage LMX2352 DS100831-9 Charge Pump Current vs CP RF_CP_WORD = 0000 and 0111 ...
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Typical Performance Characteristics Charge Pump Current vs CP Voltage O RF_CP_WORD = 0011 and 1111 RF Input Impedance V = 2.7V to 5.5V MHz GHz (f Capacitor = 100 pF) IN www.national.com (Continued) ...
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... Typical Performance Characteristics LMX2350 RF Sensitivity vs Frequency IF Input Sensitivity vs Frequency LMX2350 V Voltage vs V Load Current in Vdoubler P P Mode 25˚C (Continued) LMX2352 RF Sensitivity vs Frequency DS100831-17 Oscillator Input Sensitivity vs Frequency DS100831-19 DS100831-21 9 DS100831-18 DS100831-20 www.national.com ...
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... The integer part is configured bit A Counter www.national.com and a 10 bit B Counter. The LMX2350 is capable of operat- ing from 500 MHz to 1.2 GHz with the 16/17 prescaler offering a continuous integer divide range from 272 to 16399, and 1 ...
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Functional Description and 3.2.2). The phase detector also receives a feedback signal from the charge pump, in order to eliminate dead zone. 1.5 Charge Pump The phase detector’s current source outputs pump charge into an external loop filter, which then ...
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Programming Description 2.0 INPUT DATA REGISTER The descriptions below describe the 24-bit data register loaded through the MICROWIRE Interface. The data register is used to program the 15-bit IF_R counter register, and the 15-bit RF_R counter register, the 15-bit IF_N ...
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Programming Description 3.1.3 15-BIT PROGRAMMABLE REFERENCE DIVIDER RATIO (R COUNTER) Divide Ratio 32,767 Notes: Divide ratio 32,767 (Divide ratios less ...
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Programming Description 3.2.1 (RF_R [22 - 23] ) DLL_MODE V2_EN BIT LOCATION DLL_MODE RF_R [23] V2_EN RF_R [22] 1. V2_EN bit when set high enables the voltage doubler for the RF Charge Pump supply. 2. DLL_MODE bit should be set ...
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... Both synchronous and asynchronous power down modes are available with the LMX2350 family in order to adapt to different types of applications. The power down mode bit IF_N[21] is used to select between synchronous and asyn- chronous power down ...
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... RF SWALLOW COUNTER DIVIDE RATIO (Continued) (RF A COUNTER) Swallow Count ( Note: Swallow Counter Value LMX2350 31; LMX2352 RF_NB_CNTR 4.2.3 10-BIT RF PROGRAMMABLE COUNTER DIVIDE RATIO (RF B COUNTER) Divide Ratio 1,023 Note: Divide ratio 1023 (Divide ratios less than 3 are prohibited) ...
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Programming Description 4.4.1 Programmable CMOS Output Truth Table BIT LOCATION OUT_0 IF_N[17] OUT_1 IF_N[18] FastLock IF_N[20] When the FastLock bit is set to one, OUT_0 and OUT_1 are don’t care bits. FastLock mode utilizes the OUT0 and OUT1 output pins ...
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Programming Description 4.6 LOCK DETECT DIGITAL FILTER The Lock Detect Digital Filter compares the difference between the phase of the inputs of the phase detector generated delay of approximately 15nS. To enter the locked state (Lock = ...
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Programming Description 4.7 ANALOG LOCK DETECT FILTER When the Fo/LD output is configured in analog lock detect mode an external lock detect circuit is needed in order to provide a steady LOW signal when the PLL is in the locked ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted Molded TSSOP, JEDEC Plastic Package (MTC24) Order Number LMX2350TM or LMX2352TM NS Package MTC24 20 ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) unless otherwise noted (Continued) Molded CSP, JEDEC Plastic Package (SLB24A) Order Number LMX2350SLB or LMX2352SLB NS Package SLB24A 2. A critical component is any component of a life ...