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ig rfo rm lta -S ig r D l P tin re th ize May 2007 LMX2487E 7.5 GHz High Performance Delta-Sigma Low Power Dual PLLatinum™ Frequency Synthesizers with 3.0 GHz Integer PLL WLAN Standards General Descri...
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Connection Diagram Top View 24-Pin LLP (SQ) Pin Descriptions Pin # Pin Name I/O Pin Description GND Ground Substrate. This is on the bottom of the package and must be grounded. CPout RF RF PLL charge ...
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Absolute Maximum Ratings (Notes 1, 2) Value Parameter Symbol Units Min Typ Max Power Supply Voltage VCC -0.3 4.25 Voltage on any pin with GND = 0V Vi -0.3 VCC+0.3 Storage Temperature Range Ts -65 +150...
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Value Symbol Parameter Conditions Units Min Typ Max RF_CPG = 0 VCPout RF = VCC/2 RF Charge Pump Sink RF_CPG = 1 ICPout RFSINK Current VCPout RF = VCC/2 (Note 4) µA RF_CPG = 15 VCPout RF = VCC/2 RF Cha...
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Value Symbol Parameter Conditions Units Min Typ Max PHASE NOISE RF_CPG = 0 -202 RF Synthesizer RF_CPG = 1 -204 LF1Hz RF Normalized Phase Noise RF_CPG = 3 -206 d Bc/Hz Contribution(Note 6) RF_CPG = 7 -...
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Typical Performance Characteristics : Sensitivity (Note 7) RF PLL Fin Sensitivity TA = 25°C, RF_P = 32 RF PLL Fin Sensitivity VCC = 3.0 V, RF_P = 32 www.national.com
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IF PLL Fin Sensitivity TA = 25°C, IF_P = 16 IF PLL Fin Sensitivity VCC = 3.0 V, IF_P = 16 www.national.com
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OSCin Sensitivity TA = 25°C, OSC_2X = 0 OSCin Sensitivity VCC = 3.0 V, OSC_2X = 0 www.national.com
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OSCin Sensitivity TA = 25°C, OSC_2X =1 OSCin Sensitivity VCC = 3.0 V, OSC_2X = 1 www.national.com
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Typical Performance Characteristic : Fin RF Input Impedance (Note 7) Fin RF Input Impedance Frequency (MHz) Real (Ohms) Imaginary (Ohms) www.national.com
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Typical Performance Characteristic : Fin IF Input Impedance (Note 7) Fin IF Input Impedance Frequency (MHz) Real (Ohms) Imaginary (Ohms) www.national.com
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Typical Performance Characteristic : OSCin Input Impedance (Note 7) Frequency Powered Up Powered Down (MHz) Real Imaginary Magnitude Real Imaginary Magnitude www.national.com
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Typical Performance Characteristics : Currents (Note 7) Power Supply Current CE = High RF PLL Charge Pump Current VCC = 3.0 Volts www.national.com
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IF PLL Charge Pump Current VCC = 3.0 Volts Charge Pump Leakage RF PLL VCC = 3.0 Volts www.national.com
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Charge Pump Leakage IF PLL VCC = 3.0 Volts Note 7: Typical performance characteristics do not imply any sort of guarantee. Guaranteed specifications are in the electrical characteristics section. www....
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Bench Test Setups Charge Pump Current Measurement Procedure The above block diagram shows the test procedure for testing the RF and IF charge pumps. These tests include absolute current level, mismatc...
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Charge Pump Current Specification Definitions I1 = Charge Pump Sink Current at VCPout = Vcc - ΔV I2 = Charge Pump Sink Current at VCPout = Vcc/2 I3 = Charge Pump Sink Current at VCPout = ΔV I4 = Charg...
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Frequency Input Pin DC Blocking Capacitor Corresponding Default Counter Value MUX Value Counter OSCin 1000 p F RF_R / 2 Fin RF 100 p F// 1000 p F RF_N / 2 502 + 2097150 / Fin IF 100 p F IF_N / 2 OSCin...
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Input Impedance Measurement Procedure The above block diagram shows the test setup used for measuring the input impedance for the LMX2487E. The DC blocking capacitor used between the input SMA connect...
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erences available, such as the one given at the end of the Functional Description (Note 8) functional description block. 1.0 GENERAL 1.5 N COUNTERS AND HIGH FREQUENCY INPUT PINS The LMX2487E consists ...
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CE Pin RF_PD ATPU PLL State Bit Enabled + Write to RF N Counter Low Powered Down (Asynchronous) High Yes Powered Up High No Powered Up High No Powered Down ( Asynchronous ) 1.7 DIGITAL LOCK DETECT OPE...
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1.8 CYCLE SLIP REDUCTION AND FASTLOCK 1.8.1 Using Cycle Slip Reduction (CSR) to Avoid Cycle Slipping The LMX2487E offers both cycle slip reduction (CSR) and Fastlock with timeout counter support. This...
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never recommended. In this case, the value for R2p is typi- ally one-half or one-fourth. There are trade-offs between frac- cally about 80% of what it would be for a second order filter. tional spurs,...
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Programming Description 2.0 GENERAL PROGRAMMING INFORMATION The 24-bit data registers are loaded through a MICROWIRE Interface. These data registers are used to program the R counter, the N counter, a...
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Quick Start Register Map Although it is highly recommended that the user eventually take advantage of all the modes of the LMX2487E, the quick start register map is shown in order for the user to get ...
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2.1 R0 REGISTER Note that this register has only one control bit, so the N counter value to be changed with a single write statement to the PLL. REGISTER DATA[22:0] C0 R0 RF_N[10:0] RF_FN[11:0] 2.1.1 ...
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2.2 R1 REGISTER REGISTER DATA[19:0] C3 C2 C1 C0 R1 RF_PD RF_P RF_R[5:0] RF_FD[11:0] 2.2.1 RF_FD[11:0] -- RF PLL Fractional Denominator The function of these bits are described in section 2.6.2. 2.2.2 ...
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2.3 R2 REGISTER REGISTER DATA[19:0] C3 C2 C1 C0 R2 IF_PD IF_N[18:0] 2.3.1 IF_N[18:0] -- IF N Divider Value IF_N Counter Programming with the 8/9 Prescaler (IF_P=0) IF_N[18:0] N Value IF_B IF_A ≤23 N v...
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2.4 R3 REGISTER REGISTER DATA[19:0] C3 C2 C1 C0 R3 ACCESS[3:0] RF_CPG[3:0] IF_R[11:0] 2.4.1 IF_R[11:0] -- IF R Divider Value For the IF R divider, the R value is determined by the IF_R[11:0] bits in t...
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Register
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2.5 R4 REGISTER This register controls the conditions for the RF PLL in Fastlock. REGISTER DATA[19:0] C3 C2 C1 C0 DITH FM OSC_ OSC_ IF_ RF_ MUX R4 ATPU IF_P [1:0] [1:0] 2X OUT CPP CPP [3:0] 2.5.1 MUX[...
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2.5.5 OSC_OUT Oscillator Output Buffer Enable OSC_OUT OSCout Pin Disabled (High Impedance) Buffered output of OSCin pin 2.5.6 OSC2X -- Oscillator Doubler Enable When this bit is set to 0, the oscillat...
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2.6 R5 REGISTER REGISTER DATA[19:0] C3 C2 C1 C0 R5 RF_FD[21:12] RF_FN[21:12] 2.6.1 Fractional Numerator Determination { RF_FN[21:12], RF_FN[11:0], ACCESS[1] } In the case that the ACCESS[1] bit is 0, ...
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2.7 R6 REGISTER REGISTER DATA[19:0] C3 C2 C1 C0 R6 CSR[1:0] RF_CPF[3:0] RF_TOC[13:0] 2.7.1 RF_TOC -- RF Time Out Counter and Control for FLout RF Pin The RF_TOC[13:0] word controls the operation of th...
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CSR CSR State Sample Rate Reduction Factor Disabled Enabled 1/2 Enabled 1/4 Enabled 1/16 www.national.com
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2.8 R7 REGISTER REGISTER Data[19:0] C3 C2 C1 C0 2.8.1 DIV4 -- RF Digital Lock Detect Divide By 4 Because the digital lock detect function is based on a phase error, it becomes more difficult to detect...
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Physical Dimensions inches (millimeters) unless otherwise noted Plastic Quad LLP (SQ), Bottom View Order Number LMX2487ESQXfor 4500 Unit Reel Order Number LMX2487ESQ for 1000 Unit Reel NS Package Numb...
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ig rf rm lt -S ig ti re th iz Notes THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANT...
