ADA4937-1 Analog Devices, ADA4937-1 Datasheet - Page 17

• Manufacturer Part Number: ADA4937-1
• Description: Ultra-Low Distortion Differential ADC Driver
• Manufacturer: Analog Devices

OPERATIONAL DESCRIPTION
DEFINITION OF TERMS
Differential Voltage
This refers to the difference between two node voltages. For
example, the output differential voltage (or equivalently, output
differential-mode voltage) is defined as
where V
−OUT terminals with respect to a common reference.
V
OUT, dm
+OUT
V
+D
–D
OCM
+FB
–FB
IN
IN
= (V
and V
R
R
+OUT
G
G
−OUT
Figure 46. Circuit Definitions
R
R
− V
F
F
refer to the voltages at the +OUT and
+IN
–IN
−OUT
ADA4937-1
)
–OUT
+OUT
R
L, dm
V
OUT, dm
Rev. 0 | Page 17 of 28
Common-Mode Voltage
This refers to the average of two node voltages. The output
common-mode voltage is defined as
Balance
Balance is a measure of how well differential signals are
matched in amplitude and are exactly 180° apart in phase.
Balance is most easily determined by placing a well-matched
resistor divider between the differential voltage nodes and
comparing the magnitude of the signal at the divider’s midpoint
with the magnitude of the differential signal (see Figure 44). By
this definition, output balance is the magnitude of the output
common-mode voltage divided by the magnitude of the output
differential mode voltage.
V
Output
OUT, cm
= (V
Balance
+OUT
+ V
Error
−OUT
=
)/2
V
V
OUT
OUT
,
,
dm
cm
ADA4937-1