Sacher Lasertechnik LB2001 - PI Filter

Operation Manual LB2001 Sacher Lasertechnik
GmbH
_____________________________________________________________________________________________________
Adress:
Sacher Lasertechnik GmbH
Rudolf-Breitscheid-Str. 1-5
D-35037 Marburg, Germany
Tel.: +49 (6421) 305-0
Fax.: +49 (6421) 305-299
EMail: contact@sacher-laser.com
Web: http://www.sacher-laser.com
Sacher Lasertechnik, LLC
5765 Equador Way
Buena Park, CA 90620, USA
Tel.: 1-714-670-7605
Fax: 1-714-670-7662
Email: sales@sacher-
laser.com
Page 19
Version:
Preliminary 2011-01-01
5.3. PI Filter
This section converts the error signal to a control signal with a proportional-integral
(P-I) filter. Front panel controls adjust the overall loop gain, the P-I corner frequency,
and an optional low-frequency gain limit. A toggle switch is used to disable/enable
the output of the P-I filter for acquiring lock. See the next section for more details
about the transfer functions available from this filter. An optional TTL input can be
used to disable the error signal input and hold the P-I filter output at its current value
.
PI Filter
UnLock
Lock PreLock
PI Corner
(fpi)
LF Limit
(g)
Gain
(K)
KLFGLp fpi, K, g, ( )
K
1
g p⋅
2 π⋅ fpi⋅
+
g








1
p
2 π⋅ fpi⋅
+






⋅:=
Limit
Int
Hold