LMX3305 National Semiconductor, LMX3305 Datasheet
LMX3305
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LMX3305 Summary of contents
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... LMX3305 via a microwire interface (Clock, Data, & LE). The RF PLL provides a fastlock feature allowing the loop bandwidth to be increased by 3X during initial lock-on. The supply voltage of the LMX3305 ranges from 2.7V to 3.6V. It typically consumes supply current and is packaged in a 24-pin CSP package. Block Diagram TRI-STATE ® ...
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... Functional Block Diagram Connection Diagram www.national.com DS101361-3 Top View Order Number LMX3305SLBX See NS Package Number SLB24A 2 DS101361-2 ...
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Pin Descriptions Pin No. Pin Name I/O 1 RF_CP RF_GND PWR 3 RF_F RF_V PWR CC 5 Lock_Det O 6 N/C 7 RF_En I 8 Rx_En I 9 Tx_En I 10 Clock I 11 ...
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Absolute Maximum Ratings Power Supply Voltage (PLL (Note 3) Supply Voltage ( Voltage on any Pin with GND = Storage Temperature Range ( Lead Temp. (solder, 4 sec.) (T ...
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Electrical Characteristics < < 3V, −30˚C T 85˚C except as specified Symbol Parameter DIGITAL INPUTS AND OUTPUTS t Data to Clock Setup Time CS t Data to Clock Hold Time CH t Clock ...
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Charge Pump Current Specification Definitions sink current − sink current sink current ...
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... MHz–600 MHz. The Rx and Tx N-counters do not include fractional compensation. 1.5 FRACTIONAL COMPENSATION The fractional compensation circuitry of the LMX3305 RF di- vider allows the user to adjust the VCO tuning resolution in 1/2 through 1/16th increments of the phase detector com- parison frequency. A 4-bit denominator register (FRAC_D) selects the fractional modulo base ...
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... LOCK DETECT OUTPUTS The open-drain Lock Detect is available in the LMX3305 to provide a digital or analog lock detect indication for the sum of the active PLLs. In the digital lock detect mode, an internal digital filter produces a logic level HIGH at the lock detect output when the error between the phase detector inputs is less than 15 ns for five consecutive comparison cycles ...
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Programming Description P IF_R0 IF_N0 Rx_RST IF_R1 Rx_PWDN IF_N1 RF_RST Rx_PD_POL IF_R2 IF_N2 RF_PD_POL IF_R3 IF_N3 IF_R4 IF_N4 RF_Icpo IF_R5 IF_N5 IF_R6 IF_N6 IF_R7 IF_N7 IF_R8 IF_N8 IF_R9 IF_N9 IF_R10 IF_N10 FSTSW1 IF_R11 IF_N11 FSTSW2 IF_R12 IF_N12 IF_R13 IF_N13 ...
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Programming Description Rx_RST Rx_PD_POL Tx_RST Tx_PD_POL P www.national.com (Continued) IF_R0 IF_N0 V2X IF_R1 Rx_PWDN IF_N1 RF_RST IF_R2 IF_N2 RF_PD_POL IF_R3 IF_N3 IF_R4 IF_N4 RF_Icpo IF_R5 IF_N5 IF_R6 IF_N6 IF_R7 IF_N7 IF_R8 IF_N8 IF_R9 IF_N9 IF_R10 IF_N10 FSTSW1 IF_R11 IF_N11 ...
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Programming Description (Continued) IF_R0 Rx_RST IF_R1 Rx_PD_POL IF_R2 IF_R3 IF_R4 IF_R5 IF_R6 IF_R7 IF_R8 IF_R9 IF_R10 IF_R11 IF_R12 IF_R13 IF_R14 IF_R15 IF_R16 Tx_RST IF_R17 Tx_PD_POL IF_R18 IF_R19 IF_R20 IF_R21 IF_R22 IF_R23 IF_R24 IF_R25 IF_R26 IF_R27 IF_R28 IF_R 11 www.national.com ...
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Programming Description 2.3.1 10-Bit IF Programming Reference Divider Ratio (Tx R Counter Counter) Divide Ratio 2 3 • 1023 Note: Divide ratio for both Tx and Rx R counters are from 2 to 1023. 2.3.2 Tx_PD_POL (IF_R[18]) ...
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Programming Description (Continued) 13 DS101361-5 www.national.com ...
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Programming Description Typical Lock Detect Timing 2.3.5 Rx_PD_POL (IF_R[2]) This bit sets the polarity of the Rx phase detector set to one when Rx VCO characteristics are positive. When Rx VCO fre- quency decreases with increasing control ...
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Programming Description (Continued) IF_N0 Rx_PWDN IF_N1 IF_N2 IF_N3 IF_N4 IF_N5 IF_N6 IF_N7 IF_N8 IF_N9 IF_N10 IF_N11 IF_N12 IF_N13 IF_N14 IF_N15 Tx_PWDN IF_N16 IF_N17 IF_N18 IF_N19 IF_N20 IF_N21 IF_N22 IF_N23 IF_N24 IF_N25 IF_N26 IF_N27 IF_N28 IF_N 15 www.national.com ...
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Programming Description 2.4.1 3-Bit IF Swallow Counter Divide Ratio (Tx A Counter Counter) Divide Ratio 0 1 • 7 Divide ratio is from Tx_NB_CNTR 2.4.2 10-Bit IF Programmable Counter Divide Ratio (Tx B Counter, ...
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Programming Description (Continued) V2X RF_R0 RF_RST RF_R1 RF_PD_POL RF_R2 RF_R3 RF_Icpo RF_R4 RF_R5 RF_R6 RF_R7 RF_R8 RF_R9 RF_R10 FSTSW1 RF_R11 FSTSW2 FSTM1 RF_R12 FSTM2 RF_R13 RF_R14 RF_R15 RF_R16 RF_R17 RF_R18 RF_R19 RF_R20 RF_R21 RF_R22 RF_R23 RF_R24 RF_R25 RF_R26 RF_R27 ...
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... PLL. Consistent gain and phase margins are maintained by simultaneously changing charge pump current magnitude and loop filter damping resistor. In the LMX3305, the RF fastlock can achieve substantial improvement in lock time by increasing the charge pump current by 4X 9X, which causes a 2X, 2. increase in the loop bandwidth respectively. ...
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Programming Description 2.5.5 RF_Icpo (RF_R[4]-[3]) These two bits set the charge pump gain of the RF PLL. The user is able to set the charge pump gain during the acquisition phase of the fastlock mode to 4X ...
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Programming Description www.national.com (Continued) RF_N0 RF_N1 RF_N2 RF_PWDN RF_N3 RF_N4 PCS Fbps RF_N5 RF_N6 RF_N7 RF_N8 RF_N9 RF_N10 RF_N11 RF_N12 RF_N13 RF_N14 RF_N15 RF_N16 RF_N17 RF_N18 RF_N19 RF_N20 RF_N21 RF_N22 RF_N23 RF_N24 RF_N25 RF_N26 RF_N27 RF_N28 RF_N 20 ...
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Programming Description 2.6.1 RF_N_CNTR (RF_N[28]-[14]) The RF N counter value is determined by three counter values that work in conjunction with four prescalers. This quadruple modulus prescaler architecture allows lower minimum continuous divide ratios than are possible with a ...
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Programming Description 2.6.3 FRAC_D (RF_N[9]-[6]) These four bits, the fractional accumulator modulus denominator, set the fractional denominator from 1/2 to 1/16 resolution. Modulus Denominator 1-8 9 10- MODULUS NUMERATOR (FRAC_N) AND DENOMINATOR (FRAC_D) PROGRAMMING Fractional Numerator (FRAC_N) ...
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Programming 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 ...
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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 LMX3305 Package Drawing Order Number LMX3305SLBX NS Package Number SLB24A 2. A critical component is any component of a life ...