Texas Instruments THS4031, User Manual

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Description
1-3 General
1.2 Description
The TI THS4031 high-speed operational amplifier evaluation module (EVM)
is a complete high-speed amplifier circuit. It consists of the TI THS4031
high-speed, low-power operational amplifier IC, along with a small number of
passive parts, mounted on a small circuit board measuring approximately
1.7 inch by 1.4 inch (Figure 1–1). The EVM uses standard SMA miniature RF
connectors for inputs and outputs and is completely assembled, fully tested,
and ready to use — just connect it to power, a signal source, and a load
(if desired).
Figure 1–1. THS4031 Evaluation Module
NONINVERTING
+
R4
R2
+VCC
C1
R1
C3
C2
GND
–VCC
R5
C4
R3
U1
J2
–IN
GND
J4
OUT
GND
J3
+IN
GND
INVERTING
SLOP203
THS4031 EVM Board
J1
INSTRUMENTS
+
TEXAS
The THS4031 EVM is equipped with both noninverting and inverting inputs.
The noninverting input is set for a gain of + 2 and the inverting input is set for
a gain of –1. Each input is terminated with a 50-
Ω
resistor to provide correct
line impedance matching (Figure 1–2). The amplifier IC output is routed
through a 50-
Ω
resistor, both to provide correct line impedance matching and
to help isolate capacitive loading on the output of the amplifier. Capacitive
loading directly on the output of the IC decreases the amplifier’s phase margin
and can result in peaking or oscillations.