ADA4932-1 AD [Analog Devices], ADA4932-1 Datasheet - Page 19

• Manufacturer Part Number: ADA4932-1
• Description: Low Power Differential ADC Driver
• Manufacturer: AD [Analog Devices]

THEORY OF OPERATION
The ADA4932-x differs from conventional op amps in that it
has two outputs whose voltages move in opposite directions and
an additional input, V
loop gain and negative feedback to force these outputs to the
desired voltages. The ADA4932-x behaves much like a standard
voltage feedback op amp and facilitates single-ended-to-differential
conversions, common-mode level shifting, and amplifications of
differential signals. Like an op amp, the ADA4932-x has high input
impedance and low output impedance. Because it uses voltage
feedback, the ADA4932-x manifests a nominally constant gain
bandwidth product.
Two feedback loops are employed to control the differential and
common-mode output voltages. The differential feedback, set
OCM
. Like an op amp, it relies on high open-
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with external resistors, controls only the differential output voltage.
The common-mode feedback controls only the common-mode
output voltage. This architecture makes it easy to set the output
common-mode level to any arbitrary value within the specified
limits. The output common-mode voltage is forced, by the internal
common-mode feedback loop, to be equal to the voltage applied
to the V
The internal common-mode feedback loop produces outputs
that are highly balanced over a wide frequency range without
requiring tightly matched external components. This results in
differential outputs that are very close to the ideal of being
identical in amplitude and are exactly 180° apart in phase.
OCM
input.
ADA4932-1/ADA4932-2