40 lines
1.1 KiB
Plaintext
40 lines
1.1 KiB
Plaintext
This directory contains a mixed mode pll, combining
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ngspice and XSPICE circuit blocks.
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The pll consists of the following blocks:
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** voltage controlled oscillator:
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vco_sub.cir
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7 stage ring oscillator with gain cells, CMOS devices
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or
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vco_sub_new.cir
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vco made from code model d_osc, cntl_array/freq_array data
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are gained by running test-vco.cir with vco_sub.cir
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** digital divider and frequency reference:
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pll-xspice.cir
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** phase frequency detector:
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f-p-det-d-sub.cir
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** loop filter:
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loop-filter.cir
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switched current sources as charge pump, 2nd order
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passive RC filter
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or
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loop-filter-2.cir
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transistors as switches for charge pump, 2nd or 3rd
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order passive RC filters
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** main simulation control:
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pll-xspice.cir
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Two test files are included:
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test-vco.cir simulates vco frequency versus control voltage
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test-f-p-det.cir simulates the phase frequency detector and the loop filter.
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The main building blocks are organised as subcircuits.
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main simulation control with three reference frequencies:
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pll-xspice-fstep.cir
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simulates two steps of the reference in one simulation run
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