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AN1420.0
August 28, 2008
establish a ground referenced input for dual supply
operation, or can be externally set to any reference level for
single supply operation. VREF should not be left floating.
User-selectable Options (
Figures 3 and
4)
Component pads are included to enable a variety of
user-selectable circuits to be added to the amplifier VREF,
inputs, outputs, and the amplifier feedback loops. The inputs
(Figure 3) have additional resistor and capacitor, and jumper
placements for loading and/or measurement of frequency
sensitive parameters.
The outputs (see Figure 4) have a 10k
Ω
load resistor to
ground and have additional resistor and capacitor
placements for loading.
Note: Operational amplifiers are sensitive to output
capacitance and may oscillate. In the event of oscillation,
reduce output capacitance by using shorter cables or add a
resistor in series with the output.
FIGURE 3. INPUT STAGE (1/2)
FIGURE 4. OUTPUT STAGE (1/2)
IN-
OUT
NODE
IN+
C1
R5
R4
J2
J1
R1
R6
R17
R2
R14
R3
R18
R15
R12
R10
R13
R11
DNP
DNP
DNP
DNP
DNP
DNP
DNP
OPEN
DNP
DN
P
10k
100k
100k
10k
0
VREF
TO OUTPUT
TO IN+
TO IN-
R26
C6
C8
R2
8
10
k
O
PEN
OPEN
0
FROM OUTPUT
Application Note 1420
