Datasheet

LT1990
13
1990fb
Large Signal Transient Response
Small Signal Transient Response Small Signal Transient Response
TYPICAL PERFOR A CE CHARACTERISTICS
UW
5V/DIV
V
S
= ±15V
G = 1, –1
R
L
= 10k
V
REF
= GND
50µs/DIV
GND
1990 G30
50mV/DIV 50mV/DIV
V
S
= ±15V
G = 1, –1
R
L
= 10k
V
REF
= GND
V
S
= 3V, 0V
G = 1, –1
R
L
= 10k
V
REF
= 1.5V
50µs/DIV 50µs/DIV
GND
1.5V
1990 G28 1990 G29
–
+
6
8
5
7
2
3
4
1
V
+
–IN
V
–
+IN
REF
GAIN1
OUT
GAIN2
R5
900k
R7
10k
R10
10k
R1
1M
R2
1M
R6
100k
R9
100k
R4
40k
R3
40k
R8
900k
1990 SS
BLOCK DIAGRA
W
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
–
(Pin 4): Negative Power Supply. Can be either ground
(in single supply applications) or a negative voltage (in
split supply applications).
GAIN2 (Pin 5): Gain = 10 Select Input. Configures the
amplifier for a gain of 10 when connected to the GAIN1 pin
and the REF pin. The gain is equal to one when both GAIN2
and GAIN1 are open. See Applications section for addi-
tional functions.
OUT (Pin 6): Output. V
OUT
= G • (V
+IN
– V
–IN
) + V
REF
, in the
basic configuration.
V
+
(Pin 7): Positive Power Supply. Can range from 2.7V to
36V above the V
–
voltage.
GAIN1 (Pin 8): Gain = 10 Select Input. Configures the
amplifier for a gain of 10 when connected to the GAIN2 pin
and the REF pin. The gain is equal to one when both GAIN1
and GAIN2 are open. See Applications section for addi-
tional functions.
UU
U
PI FU CTIO S