Omega Engineering OMB-DBK-34A, User Manual

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DBK18
4-Channel Low-Pass Filter Card
Overview ...... 1
Hardware Setup ...... 1
Card Connection ...... 1
Card Configuration ...... 2
CE Compliance ...... 3
DaqBook/100 Series & /200 Series and DaqBoard [ISA type] Configuration ...... 3
DaqBook/2000 Series and DaqBoard/2000 Series Configuration ...... 3
Configuring DBK18 Filter Sections ...... 3
Software Setup ...... 5
DBK18 – Specifications ...... 6
Reference Notes :
o
Chapter 2 includes pinouts for P1, P2, P3, and P4. Refer to pinouts applicable
to your system, as needed.
o
In regard to calculating system power requirements, refer to DBK Basics located
near the front of this manual.
Overview
Each DBK18 low-pass filter (LPF) card provides 4 input channels to a LogBook or a Daq device system.
Each of sixteen channels can accept four DBK18 cards for a maximum of 256 analog inputs. The input
connectors are BNC type connectors. The differential inputs are provided with switchable 100 K
Ω
bias
resistors to analog common.
The DBK18 features an instrumentation amplifier for each channel, with switch-selected gains of
×1, ×10, ×100, ×200 and ×500. A socket is provided for a gain resistor for custom gain selection instead
of unity gain (×1). Gain for any channel can be set to any value between unity and ×500 by installing an
appropriate resistor. Four separate filter stages follow the 4 input stages. The outputs are connected to a
4-channel multiplexer stage. The enabled output MUX allows up to four DBK18s to share a common
analog base channel.
Amplifier
SW5
BNC
CH 1
CH 2
CH 3
CH 0 (1 of 4 identical channels)
Switchable
bias resistors
(per channel)
a
f
LPF
Low-Pass
Filter
Gain-Select Switches
SW1-SW4
P1
Channel address lines
MUX
2
2
16
J1 Output channel
selection header
Card Address
recognition stage
EN
BY
Filter-Bypass/
Enable Jumpers
J3-J6
Board-Select
Switch
SW6
DBK18 Block Diagram
Terminal
Block
+ _
Hardware Setup
Card Connection
The DBK18 is equipped with BNC connectors for easy access to all of the analog inputs. Connections are
provided for 4 differential inputs. The card also includes a terminal block as a connection-option to the
BNC connectors.
Note : New versions of the DBK18 have been enhanced by the addition of a terminal block. The BNC
connectors are still usable, and board functions have not been changed.
DBK Option Cards and Modules
918894
DBK18, pg. 1