LMX2370 National Semiconductor, LMX2370 Datasheet
LMX2370
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LMX2370 Summary of contents
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... Serial data is transferred into the LMX237X via a 1.8V three wire interface (Data, En- able, Clock) compatible with low voltage baseband proces- sors. Supply voltage can range from 2.7V to 5.5V. The LMX237X family features very low current consumption typi- cally: LMX2370 - 6 3V, LMX2371 - 5 LMX2372 - 4 ...
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... Connection Diagrams TSSOP 20-Pin Package DS101026-2 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 — ...
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Pin Descriptions (Continued) Pin No. Pin I/O 24-Pin 20-Pin Name CSP TSSOP 16 14 Vµc — GND — GND — Vp2 — ...
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... ESD - Human Body Model (Note 2) Electrical Characteristics GENERAL Symbol Parameter I Power Supply LMX2370 CC Current LMX2371 LMX2372 LMX2370 /71/72 I Power Down Current CC-PWDN f 1 Main PLL LMX2370 IN Operating Frequency LMX2371 LMX2372 f 2 Auxiliary PLL Operating IN Frequency Zf Main Main PLL Input Impedance IN Zf Aux Aux Input Impedance IN f ...
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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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... The synthesizer can be programmed even in power down state. A complete programming description is followed in Section 2.0. 1.8 MULTIFUNCTION OUTPUTS The LMX2370/LMX2371/LMX2372 FoLD output pin can be configured as the FastLock output or CMOS programmed output, analog lock detects as well as showing the internal block status such as the counter outputs. 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 ...
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Functional Description The reference oscillator input block is powered down when both Main_PWDN and Aux_PWDN bits are asserted. The OSC reverts to a high impedance state when this condition exists. Power down forces the respective charge pump and phase ...
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Programming Description www.national.com (Continued) 8 ...
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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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... 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 and LMX2371 respectively. The 16/17 prescaler is only rated for input frequencies below 1.2 GHz. A 16/ 8/9 prescaler can be selected for the both 1.2 GHz synthesizers on the LMX2372 as well as the 1 ...
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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 Aux R[18] R[18] R[19] R[19 ...
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Programming Description (Continued) 2.6 Typical Lock Detect Timing www.national.com Typical Lock Detect Timing 14 DS101026-7 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Thin Shrink Small Outline (TSSOP) Package Order Number LMX2370TM, LMX2371TM or LMX2372TM * For Tape and Reel (2500 units per reel) Order Number LMX2370TMX, LMX2371TMX or LMX2372TMX NS Package Number MTC20 15 www.national.com ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Numbers: LMX2370SLBX, LMX2371SLBX, LMX2372SLBX 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 OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1 ...