LMH1982SQEEVAL/NOPB National Semiconductor, LMH1982SQEEVAL/NOPB Datasheet
LMH1982SQEEVAL/NOPB
Specifications of LMH1982SQEEVAL/NOPB
Related parts for LMH1982SQEEVAL/NOPB
LMH1982SQEEVAL/NOPB Summary of contents
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... FIGURE 3. ....................................................................................................................................... 5 FIGURE 4. ....................................................................................................................................... 6 FIGURE 5. ....................................................................................................................................... 6 FIGURE 6. ....................................................................................................................................... 7 FIGURE 7. ....................................................................................................................................... 8 FIGURE 8. ....................................................................................................................................... 8 TABLE.1 .......................................................................................................................................... 2 TABLE.2 .......................................................................................................................................... 2 TABLE.3 .......................................................................................................................................... 3 TABLE.4 .......................................................................................................................................... 3 TABLE.5 .......................................................................................................................................... 3 TABLE.6 .......................................................................................................................................... 4 TABLE.7 .......................................................................................................................................... 4 TABLE.8 .......................................................................................................................................... 4 TABLE.9 .......................................................................................................................................... 5 © 2008 National Semiconductor Corporation National Semiconductor Application Note 1841 May 21, 2008 Table of Contents List of Figures List of Tables 300619 www.national.com ...
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LMH1982 Evaluation Board The LMH1982 evaluation board was designed by National Semiconductor (NSC) to evaluate the performance and op- eration of the LMH1982 multi-rate video clock and timing generator with the LMH1981 SD/HD video sync separator. The evaluation board ...
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REFERENCE PORTS The LMH1982 has two reference ports (REF_A and REF_B) with H sync and V sync inputs, which are used for phase locking the outputs in Genlock mode. The input signals can be measured at test points TP27, ...
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FIGURE 2. PCB Layout showing Loop Filter and VCXO 1.6.1 VCXO Power Supply Considerations The VCXO and LMP7701 devices operate from a separate supply plane (VDD_VCXO) derived from the board’s 3.3V supply. Resistor R5 is used to form a low-pass ...
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INTERFACE The interface clock (SCL) and data (SDA) signals come from the USB board via header J11. These signals can be probed at test points TP11 (SCL) and TP12 (SDA). Both sig- nals ...
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FIGURE 4. Schematic ( LMH1981 and LMH1980 Sync Separators FIGURE 5. Schematic ( Input Header and Switch-Controlled Logic Buffer 6 30061904 30061905 ...
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FIGURE 6. Schematic ( LMH1982 Clock Generator with Loop Filter, VCXO, and LMP7701 Op Amps 7 30061906 www.national.com ...
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Evaluation Board Layout Top Routing Layer 1 (dark gray) and Ground Plane Layer 2 (light gray) Power Plane Layer 3 (light gray) and Bottom Routing Layer 4 (dark gray) www.national.com FIGURE 7. PCB Layout ( FIGURE 8. ...
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Evaluation Board Bill of Materials Qty Part Designator C1, C4, C5, C9, C11, C12, C14, C16, C18, C19, C20, C21, C22, C23, C24, C25, C29, 20 C33, C44, C50 1 C51 C13 2 C17, C28 8 ...
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Qty Part Designator 4 4 C15, C30, C40, R13, R20, R21, R27 NP = Not Populated 5.0 References • Gerber Files: LMH1982 Evaluation PCB Layout (available upon request) • Datasheet: LMH1982 Multi-rate Video Clock Generator with Genlock • Software Manual: ...
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