Datasheet

Standard Gain Configuration
3-2
3.1 Standard Gain Configuration
The THS6182DWEVM default configuration is a fully differential input, fully
differential output gain of about 2.2 (at the output connectors using an
instrument with 50-Ω load on each input). A simplified schematic is shown in
Figure 3−1. This gain is calculated according to an equation that is similar to
the one that describes an instrumentation amplifier:
(1)
Differential gain +
V
O
(diff)
V
I
(diff)
+ 1 )
2 R2
R23
where
R2 = R11
Series resistors R6, R7, R15 and R16 affect output voltage at J1 and J3. The
designer needs to take the voltage divider law into account for their load
impedance and R6, R7, R15 and R16. When a designer monitors the output
at TP1 and TP3 using a high-impedance differential probe, the default gain is
5 V.
Figure 3−1. Default Configuration Operation
1
13
2
8
20
J3
OUT2
R2
1.5 k
R23
R15
TP1
J1
OUT1
C2
R6
12.4
TP3
+
−
U1B
THS6182
19
+V
R7
49.9
R16
TP2
TP4
0.1 F
R10
Z1
0
R9
0
J2
IN2
+
−
U1A
THS6182
R11
R19
Z2 R18
J4
IN2
750
18
−V
WW
W
49.9W
WW
3
W
m
0
0 WW
49.9W
12.4 49.9WW
1.5 k W