LT1990 Linear Technology, LT1990 Datasheet - Page 11

• Manufacturer Part Number: LT1990
• Description: Difference Amplifier
• Manufacturer: Linear Technology

PI FU CTIO S
BLOCK DIAGRA
TYPICAL PERFOR A CE CHARACTERISTICS
REF (Pin 1): Reference Input. Sets the output level when
the difference between the inputs is zero.
–IN (Pin 2): Inverting Input. Connects a 1MΩ resistor to
the op amp’s inverting input. Designed to permit high
voltage operation.
+IN (Pin 3): Noninverting Input. Connects a 1MΩ resistor
to the op amp’s noninverting input. Designed to permit
high voltage operation.
V
(in single supply applications) or a negative voltage (in
split supply applications).
–
1.5V
U
(Pin 4): Negative Power Supply. Can be either ground
Small Signal Transient Response
V
G = 1, –1
R
V
S
L
REF
= 3V, 0V
= 10k
= 1.5V
U
50µs/DIV
U
W
W
1990 G28
U
–IN
+IN
V
V
+
–
7
2
3
4
1M
1M
R1
R2
GND
REF
Small Signal Transient Response
V
G = 1, –1
R
V
1
S
REF
L
R3
40k
= ±15V
= 10k
= GND
R4
40k
–
+
900k
900k
50µs/DIV
R5
R8
GAIN2 (Pin 5): Gain = 10 Select Input. Configures the
amplifier for a gain of 10 when connected to the GAIN1 pin.
The gain is equal to one when both GAIN2 and GAIN1 are
open. See Applications section for additional functions.
OUT (Pin 6): Output. V
basic configuration.
V
36V above the V
GAIN1 (Pin 8): Gain = 10 Select Input. Configures the
amplifier for a gain of 10 when connected to the GAIN2 pin.
The gain is equal to one when both GAIN1 and GAIN2 are
open. See Applications section for additional functions.
+
(Pin 7): Positive Power Supply. Can range from 2.7V to
R6
100k
R9
100k
R10
10k
10k
R7
1990 G29
1990 SS
8
6
5
–
GAIN1
OUT
GAIN2
voltage.
OUT
GND
= G • (V
Large Signal Transient Response
V
G = 1, –1
R
V
S
REF
L
= ±15V
= 10k
= GND
+IN
– V
50µs/DIV
–IN
) + V
LT1990
REF
11
, in the
1990 G30
1990f