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PhaseFreqDetCP (Frequency Detector, Baseband with Charge Pump)

Symbol

Available in ADS and RFDE

Parameters

Name

Description

Units

Default

lhigh

High-level charge pump current

mA

1

llow

Low-level charge pump current

mA

1

DeadTime

Dead-zone pulse width

psec

0

Jitter

Input time jitter

psec

0

Notes/Equations
  1. This baseband phase-frequency demodulator with charge pump is used in transient or circuit envelope simulation.
  2. Charge pump currents can be constants (in which case they are ideal current sources) or functions of the state variable _v2 to allow for a non-ideal current whose peak value varies as a function of the output voltages. In either case, the off-state current is always 0.0. Normally positive values would be used for both currents, as Ihigh specifies a source current and Ilow specifies the sink current.
  3. DeadTime specifies the period of time centered around the 0 phase output during which no output is generated from either the high or the low charge pump. Outside of this period, the output returns to the ideal pulse widths and amplitudes determined by the trigger crossings of the inputs and the charge pump currents.
  4. The Jitter value defines the RMS time jitter associated with the trigger crossing at each of the two inputs. The effective output time jitter will be sqrt(2) times this value. The distribution is Gaussian and the noise spectrum is assumed flat out to the reference sampling frequency.
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