LMX2371TM National Semiconductor, LMX2371TM Datasheet
LMX2371TM
Specifications of LMX2371TM
Related parts for LMX2371TM
LMX2371TM Summary of contents
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... National Semiconductor Corporation. ™ ™ ™ TRI-STATE ® registered trademark of National Semiconductor Corporation. © 2000 National Semiconductor Corporation The LMX237x are available in a 24-pad chip scale (CSP 20-pin TSSOP surface mount plastic package. Features n 2.7V–5.5V operation n Ultra low current consumption ...
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... Connection Diagrams TSSOP 20-Pin Package Top View Order Number LMX2370TM, LMX2370TMX, LMX2371TM, LMX2371TMX, LMX2372TM or LMX2372TMX See NS Package Number MTC20 Pin Descriptions Pin No. Pin I/O 24-Pin 20-Pin Name CSP TSSOP — Vp1 — GND — GND — www.national.com DS101026-2 Description Power supply voltage input for RF analog and RF digital circuits ...
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Pin Descriptions (Continued) Pin No. Pin I/O 24-Pin 20-Pin Name CSP TSSOP 8 8 OSC GND — Fo/ Clock Data Vµc ...
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Pin Descriptions (Continued) Pin No. Pin I/O 24-Pin 20-Pin Name CSP TSSOP — — NC — 13, 21 Block Diagram (Note 1) Note 1: * The numbers in () represent the equivalent chipscale ...
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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 Vp1 Vp2 Vµc Voltage on any pin with GND = Storage Temperature Range ( Lead Temperature (solder, 4 sec.) (T ESD - Human Body Model (Note 3) ...
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Electrical Characteristics CHARGE PUMP Symbol Parameter ICP Charge Pump TRI-STATE o-TRI Current ICP vs CP Sink vs Source Mismatch o-sink ICP o-source ICP vs CP Current vs Voltage o VCP o ICP Current vs Temperature o A ...
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Charge Pump Current Specification Definitions sink current − sink current sink current ...
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Typical Performance Characteristics LMX2370 LMX2372 Charge Pump Current vs CP Voltage O ICP = HIGH O www.national.com LMX2371 DS101026-21 ICP TRI-STATE Voltage ...
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Typical Performance Characteristics Sink vs Source 1x-Mode Mismatch (See Note 2 under Charge Pump Current Specification Definitions) RF Input Impedance 25˚ 2.7V to 5.5V kHz to 3 GHz CC IN Marker 1 ...
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Typical Performance Characteristics LMX2370 RF Sensitivity vs Frequency LMX2372 RF Sensitivity vs Frequency Oscillator Input Sensitivity vs Frequency www.national.com (Continued) LMX2371 RF Input Sensitivity vs Frequency DS101026-31 Auxiliary Input Sensitivity vs Frequency DS101026-33 DS101026-35 10 DS101026-32 DS101026-34 ...
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... The basic phase-lock-loop (PLL) configuration consists of a high-stability crystal reference oscillator, a frequency synthesizer such as the National Semiconductor LMX2370/2371/2372, a voltage controlled oscillator (VCO), and a passive loop filter. The fre- quency synthesizer includes a phase detector, a current mode charge pump, as well as programmable reference [R] and feed- back [N] frequency dividers ...
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Functional Description 1.8.1 Lock Detect Output An analog lock detect status generated from the phase detector is available on the Fo/LD output pin, if selected. The lock detect output goes high when the charge pump is inactive. It goes ...
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Programming Description (Continued) 13 www.national.com ...
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Programming Description 2.2 PROGRAMMABLE REFERENCE DIVIDERS (Main and Aux R Counters) 2.2.1 Aux_R Register If the ADDRESS[1:0] field is set data is transferred from the 22-bit shift register into the Aux_R register when Load Enable (LE) ...
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Programming Description Most Significant Bit Aux_N 2.3.2 Main_N Register If the ADDRESS[1:0] field is set data is transferred from the 22-bit shift register into the Main_N register which sets the ...
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Programming Description 2.3.5 PLL Prescaler Select (P_Aux, P_Main) The LMX2370, LMX2371 and LMX2372 contain two dual modulus prescalers. A 32/ 16/17 prescaler can be selected for the 2.5 GHz and 2.0 GHz RF synthesizers in the LMX2370 ...
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Programming Description 2.3.7 Power Down Mode Table Main PLL Auxiliary PLL Active Active Active Powered Down Powered Down Active Powered Down Powered Down 2.4 PROGRAMMABLE MODES Several modes of operation can be programmed with bits R15–R19 including the phase ...
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Programming Description 2.4.4 The FoLD Output Truth Table Main Aux Main R[18] R[18] R[19 ...
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Programming Description (Continued) 2.6 Typical Lock Detect Timing Typical Lock Detect Timing 19 DS101026-7 www.national.com ...
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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 200 depending on the VCO ...
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Application Information A block diagram of the basic phase locked loop is shown in Figure 1 . FIGURE 1. Basic Charge Pump Phase Locked Loop LOOP GAIN EQUATIONS A linear control system model of the phase feedback for a PLL ...
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Application Information FASTLOCK CIRCUIT IMPLEMENTATION A diagram of the Fastlock scheme as implemented in Na- tional Semiconductors LMX233xA PLL is shown in Figure 5 . When a new frequency is loaded, and the RF Icp high the charge pump circuit ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number LMX2370TM, LMX2371TM or LMX2372TM Order Number LMX2370TMX, LMX2371TMX or LMX2372TMX Thin Shrink Small Outline (TSSOP) Package * For Tape and Reel (2500 units per reel) NS Package Number MTC20 23 www.national.com ...
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... 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. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...