Referenced to common | Omega OMB-DAQBOARD-500 guide

Differential mode	Differential mode voltage refers to a voltage difference between two signals that are referenced
voltage	to a common point. Example: Signal 1 is +5 VDC referenced to common. Signal 2 is +6 VDC
	referenced to common.
	If the +5 VDC signal is used as the reference, the differential mode voltage is +1 VDC
	(+ 6 VDC - +5 VDC = +1 VDC).
	If the +6 VDC signal is used as the reference, the differential mode voltage is -1 VDC
	(+ 5 VDC - +6 VDC = -1 VDC).
ESD	Electrostatic discharge (ESD) is the transfer of an electrostatic charge between bodies having
	different electrostatic potentials. This transfer occurs during direct contact of the bodies, or
	when induced by an electrostatic field. ESD energy can damage an integrated circuit (IC).
Excitation	Some transducers [e.g. strain gages, thermistors, and resistance temperature detectors
	(RTDs)] require a known voltage or current. Typically, the variation of this signal through the
	transducer corresponds to the condition measured.
Gain	The degree to which an input signal is amplified (or attenuated) to allow greater accuracy and
	resolution; can be expressed as ×n or ±dB.
Isolation	The arrangement or operation of a circuit so that signals from another circuit or device do not
	affect the isolated circuit.
	In reference to Daq devices, isolation usually refers to a separation of the direct link between
	the signal source and the analog-to-digital converter (ADC). Isolation is necessary when
	measuring high common-mode voltage.
Linearization	Some transducers produce a voltage in linear proportion to the condition measured. Other
	transducers (e.g., thermocouples) have a nonlinear response. To convert nonlinear signals
	into accurate readings requires software to calibrate several points in the range used and then
	interpolate values between these points.
Multiplexer (MUX)	A device that collects signals from several inputs and outputs them on a single channel.
Sample (reading)	The value of a signal on a channel at an instant in time. When triggered, the ADC reads the
	channel and converts the sampled value into a 12- or 16-bit value.
Scan	A series of measurements across a pre-selected sequence of channels.
Sequencer	A programmable device that manages channels and channel-specific settings.
Simultaneous	An operation that gathers samples from multiple channels at the same instant and holds these
Sample-and-Hold	values until all are sequentially converted to digital values.
Single-ended mode	The single-ended mode measures a voltage between a signal line and a common reference that
	may be shared with other channels. (Also see differential mode).
Trigger	An event to start a scan or mark an instant during an acquisition. The event can be defined in
	various ways; e.g., a TTL signal, a specified voltage level in a monitored channel, a button
	manually or mechanically engaged, a software command, etc. Some applications may use
	pre- and post-triggers to gather data around an instant or based on signal counts.
TTL	Transistor-Transistor Logic (TTL) is a circuit in which a multiple-emitter transistor has replaced
	the multiple diode cluster (of the diode-transistor logic circuit); typically used to communicate
	logic signals at 5 V.
Unipolar	A range of analog signals that is always zero or positive (e.g., 0 to 10 V). Evaluating a signal in
	the right range (unipolar or bipolar) allows greater resolution by using the full-range of the
	corresponding digital value. See bipolar.

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Glossary

referenced to common.