Texas Instruments THS6132EVM, Руководство пользователя

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Standard Gain Configuration
3-2
3.1 Standard Gain Configuration
The THS6132EVM 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
12 (20)
14(21)
3 (5)
15 (23)
2 (4)
J3
OUT2
R15
TP1
J1
OUT1
R6
TP3
+
-
U1B
THS6182
11 (18)
R7
TP2
TP4
R10
Z1
R9
J2
IN1
+
-
U1A
THS6132
Z2 R18
J4
IN2
0 0
44.9 R2
1 k
12.4 49.9
C2
0.1
F
R23
500
R11
1 k
12.4
R16
49.9
R19
44.9
0 0
Note: Component pin numbers shown are for THS6132RGW while pin numbers in parentheses are for THS6132VFP.