Doepfer A-196 PLL - Manual

doepfer System A - 100 PLL A-196
1
1. Introduction
Module A-196 contains a so-called Phase Locked
Loop circuit (PLL). A PLL consists of three parts:
VCO (linear voltage-controlled oscillator with rectangle
output), phase comparator (PC), and low-pass filter
(LPF). The three parts are connected in the A-196 with
normalled sockets to form the standard closed-loop
PLL frequency-feedback system. The normalled soc-
kets allow individual access to each part of the PLL
and enable other patches than the standard PLL (e.g.
insertion of external modules).
The VCO is equipped with the controls Range and
Offset. The range switch is used to select one of three
frequency ranges. The Offset control defines the maxi-
mum frequency of the VCO.
The module contains three different types of phase
comparators that are selected with a 3-position
switch.
The LED indicates if the PLL is locked for PC2 , i.e. if
the frequency of the internal VCO is the same as the
frequency of the external input signal.
The frequency of the built-in low pass filter is manu-
ally adjusted with the frequency control.
CV In
locked (2)
Offset
A-196
PLL
Out
In 1
Range
Out
VCO
Type
In 2
(Signal)
Out
PC
LPF
Frequ.