Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charge pump phase-locked loop with phase-frequency detector: closed form
  mathematical model   Charge pump phase-locked loop with phase-frequency detector (CP-PLL) is an
electrical circuit, widely used in digital systems for frequency synthesis and
synchronization of the clock signals. In this paper a non-linear second-order
model of CP-PLL is rigorously derived. The obtained model obviates the
shortcomings of previously known second-order models of CP-PLL. Pull-in time is
estimated for the obtained second-order CP-PLL.

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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci
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The categories of this paper are: quant-ph
3
The categories of this paper are: physics
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
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The categories of this paper are: hep-lat