THS4130CDG4 Datasheet, PDF (14/36 Pages) Texas Instruments – HIGH-SPEED, LOW-NOISE, FULLY-DIFFERENTIAL I/O AMPLIFIERS

THS4130
THS4131
SLOS318H – MAY 2000 – REVISED MAY 2011
www.ti.com
DATA CONVERTERS
Data converters are one of the most popular applications for the fully-differential amplifiers. Figure 30 shows a
typical configuration of a fully-differential amplifier attached to a differential analog-to-digital converter (ADC).
0.1 µF
V_CC
5V
V_IN
+−
V_OCM
−+
−5 V
V_CC−
V_DD
AV_DD DV_DD
A_IN1
A_{IN2 AVSS}
V_ref
Figure 30. Fully-Differential Amplifier Attached to a Differential ADC
Fully-differential amplifiers can operate with a single supply. V_OCM defaults to the midrail voltage, V_CC/2. The
differential output may be fed into a data converter. This method eliminates the use of a transformer in the circuit.
If the ADC has a reference voltage output (V_ref), then it is recommended to connect it directly to the V_OCM of the
amplifier using a bypass capacitor for stability. For proper operation, the input common-mode voltage to the input
terminal of the amplifier should not exceed the common-mode input voltage range.
0.1 µF
V_CC
5V
V_IN
+−
V_OCM
−+
V_DD
AV_DD DV_DD
A_IN1
A_{IN2 AVSS}
V_ref
Figure 31. Fully-Differential Amplifier Using a Single Supply
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