- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄364589 > AB-007 AB-007 - CLASSICAL OP AMP OR CURRENT-FEEDBACK OP AMP? PDF資料下載
參數(shù)資料
| 型號(hào)： | AB-007 |
| 英文描述： | AB-007 - CLASSICAL OP AMP OR CURRENT-FEEDBACK OP AMP? |
| 中文描述： | 抗體- 007 -古典運(yùn)算放大器或電流反饋運(yùn)算放大器？ |
| 文件頁(yè)數(shù)： | 1/2頁(yè) |
| 文件大?。?/td> | 29K |
| 代理商： | AB-007 |
5
6
7
8
10
11
12
13
14
15
9
1
4
2
The INA117 is a monolithic difference amplifier with the
unique ability to accept up to
±
200V common-mode input
signals while operating on standard
±
15V power supplies.
Because the gain of the INA117 is set at 1V/V, and because
the output would saturate into the rails at about
±
12V, the
maximum specified differential input range is
±
10V.
Since the common-mode input range is
±
200V, it makes
sense that some designers would also like to use the part for
differential inputs greater than
±
10V. Figure 1 shows the
recommended circuit. Adding resistors to the input may
seem simpler, but there are some problems with that ap-
proach.
ently of CMR by adjusting the inverter resistors, R
, R
. Gain
drift is preserved so long as R
and R
track with temperature.
Furthermore, noise at the output is improved by the gain
reduction factor whereas it is unchanged with the other
approach.
To understand how the circuit works, consider the INA117 to
be a four-input summing amplifier as shown in Figure 2.
FIGURE 1. INA117 with Increased Differential Input Range.
–
+
OPA27
–
+
8
1
5
R
7
R
6
INA117
21.1k
20.0k
R
4
R
5
380k
R
3
6
V =
V – V
19 R
1 +
R
6
2
7
V
3
V
2
380k
R
1
380k
R
2
3
2
The performance of the INA117 depends on extremely
precise resistor matching (0.005% for 86dB CMR). Resistors
added to the input must be adjusted to at least this accuracy
to maintain high performance. Both gain error and CMR
must be adjusted. Maintaining 86dB CMR over temperature
requires 1ppm/
°
C resistor TCR tracking. Significant resis-
tance added external to the INA117 would require the same
performance.
By using the circuit shown in Figure 1, internal resistor
matching is preserved, and the INA117 CMR and CMR drift
with temperature are maintained. Gain can be set independ-
FIGURE 2. INA117 Shown as a Four-Input Summing Am-
plifier.
–
+
8
1
5
V
1
INA117
21.1k
20.0k
R
4
R
5
380k
R
3
6
*V = V – V + 19 V – 18 V
V
3
V
2
380k
R
1
380k
R
2
3
2
V
5
1
*V
OUT
SELECTED-GAIN EXAMPLES
GAIN
(1)
(V/V)
R
7
(k
)
R
6
(k
)
1/2
1/4
1/5
1.05
3.16
4.22
20.0
20.0
20.0
NOTE: (1) INA117 is not stable in Gain < 1/5.
CMR is preserved and the gain is reduced if a small portion
of the output signal is inverted and fed back to pin 5 with V
1
set to zero (V
1
grounded).
Where: V
OUT
= V
3
– V
2
+ 19 V
5
– 18 V
1
If, V
5
= –V
OUT
R
7
/R
6
, then
V
3
– V
2
19 R
7
V
OUT
=
1 +
R
6
INCREASING INA117 DIFFERENTIAL INPUT RANGE
By R. Mark Stitt (520) 746-7445
1990 Burr-Brown Corporation
AB-001B
Printed in U.S.A. June, 1995
APPLICATION BULLE TIN
Mailing Address: PO Box 11400 Tucson, AZ 85734 Street Address: 6730 S. Tucson Blvd. Tucson, AZ 85706
Tel: (520) 746-1111 Twx: 910-952-111 Telex: 066-6491 FAX (520) 889-1510 Immediate Product Info: (800) 548-6132
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AB-008 | AB-008 - AC COUPLING INSTRUMENTATION AND DIFFERENCE AMPLIFIERS |
| AB-009 | AB-009 - SINGLE-SUPPLY OPERATION OF ISOLATION AMPLIFIERS |
| AB-030 | AB-030 - THERMAL AND ELECTRICAL PROPERTIES OF SELECTED PACKAGING MATERIALS |
| AB-031 | AB-031 - 4-20mA TO 0-20mA CONVERTER AND CURRENT SUMMING CURRENT-TO-CURRENT CONVERTERS |
| AB-032 | AB-032 - IC BUILDING BLOCKS FORM COMPLETE |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AB-008 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:AB-008 - AC COUPLING INSTRUMENTATION AND DIFFERENCE AMPLIFIERS |
| AB-009 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:AB-009 - SINGLE-SUPPLY OPERATION OF ISOLATION AMPLIFIERS |
| AB-010 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:AB-010 - -200V DIFFERENCE AMPLIFIER WITH COMMON-MODE VOLTAGE MONITOR |
| AB-011 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:AB-011 - LOW POWER SUPPLY VOLTAGE OPERATION OF REF102 10.0V PRECISION VOLTAGE REFERENCE |
| AB-012 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:AB-012 - BOOST ISO120 BANDWIDTH TO MORE THAN 100kHz |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。