- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄360864 > INA138 High-Side Measurement CURRENT SHUNT MONITOR PDF資料下載
參數(shù)資料
| 型號： | INA138 |
| 英文描述： | High-Side Measurement CURRENT SHUNT MONITOR |
| 中文描述： | 高側(cè)測量電流并聯(lián)監(jiān)視器 |
| 文件頁數(shù)： | 6/7頁 |
| 文件大?。?/td> | 69K |
| 代理商： | INA138 |
6
INA138, INA168
OPERATION
Figure 1 shows the basic circuit diagram for both the
INA138 and INA168. Load current, I
S
, is drawn from
supply, V
S
, through shunt resistor, R
s
. The voltage drop in
the shunt resistor, V
S
, is forced across R
g1
by the internal
op-amp, causing current to flow into the collector of Q1.
External resistor, R
L
, converts the output current to a volt-
age, V
OUT
, at the Out pin.
The transfer function for the INA138 is:
I
O
= g
m
(V
IN
+
– V
IN
–
)
(1)
where g
m
= 200
μ
A/V
(2)
In the circuit of Figure 1, the input voltage, (V
IN
equal to I
S
R
S
and the output voltage, V
OUT
, is equal to
I
O
R
L
. The transconductance, g
m
, of the INA138 is
200
μ
A/V. The complete transfer function for the current
measurement amplifier in this application is:
+
– V
IN
–
), is
V
OUT
= (I
S
) (R
S
) (200
μ
A/V) (R
L
)
(3)
The maximum differential input voltage for accurate mea-
surements is 0.5V, which produces a 100
μ
A output current.
A differential input voltage of up to 2V will not cause
damage. Differential measurements (pins 3 and 4) must be
unipolar with a more-positive voltage applied to pin 3. If a
more-negative voltage is applied to pin 3, the output current,
I
O
, will be zero, but it will not cause damage.
BASIC CONNECTION
Figure 1 shows the basic connection of the INA138. The
input pins, V
IN
possible to the shunt resistor to minimize any resistance in
series with the shunt resistance. The output resistor, R
L
, is
shown connected between pin 1 and ground. Best accuracy
is achieved with the output voltage measured directly across
R
L
. This is especially important in high-current systems
where load current could flow in the ground connections,
affecting the measurement accuracy.
No power supply bypass capacitors are required for stability
of the INA138. However, applications with noisy or high
impedance power supplies may require de-coupling capaci-
tors to reject power supply noise. Connect bypass capacitors
close to the device pins.
+
and V
IN
–
, should be connected as closely as
POWER SUPPLIES
The input circuitry of the INA138 can accurately measure
beyond its power supply voltage, V+. For example, the V+
power supply can be 5V while the load power supply is
voltage is up to +36V (or +60V with INA168). However, the
output voltage range of the Out terminal is limited by the
lesser of the two voltages (see “Output Voltage Range”).
SELECTING R
S
AND R
L
The value chosen for the shunt resistor, R
S
, depends on the
application and is a compromise between small-signal accu-
racy and maximum permissible voltage loss in the measure-
ment line. High values of R
S
provide better accuracy at
FIGURE 1. Basic Circuit Connections.
Shunt
R
S
INA138
2
1
OUT
Q1
R
L
I
0
+
V
O
–
Load
R
G1
5k
R
G2
5k
V
IN
V
IN
3
4
I
S
V+
5
NOTE: (1) Maximum V
P
and V+ voltage is 60V with INA168.
V+ power can be
common or
indepedent of
load supply.
2.7
≤
(V+)
≤
36V
(1)
V
Load Power Supply
+2.7 to 36V
(1)
+
–
VOLTAGE GAIN
EXACT R
L
(
)
NEAREST 1% R
L
(
)
1
2
5
5k
10k
25k
50k
100k
250k
500k
4.99k
10k
24.9k
49.9k
100k
249k
499k
10
20
50
100
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| INA170 | High-Side, Bidirectional CURRENT SHUNT MONITOR |
| INA170EA250 | High-Side, Bidirectional CURRENT SHUNT MONITOR |
| INA170EA2K5 | High-Side, Bidirectional CURRENT SHUNT MONITOR |
| INA193 | CURRENT SHUNT MONITOR |
| INA193AIDBVR | CURRENT SHUNT MONITOR |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| INA138_11 | 制造商:BB 制造商全稱:BB 功能描述:High-Side Measurement CURRENT SHUNT MONITOR |
| INA138NA | 制造商:Texas Instruments 功能描述:IC AMP DIFF SMD SOT-23-5 138 |
| INA138NA/250 | 功能描述:電流和電力監(jiān)控器、調(diào)節(jié)器 Hi-Sd Msmnt Current Shunt Mntr Crnt Otp RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Current Regulators 電源電壓-最大:48 V 電源電壓-最小:5.5 V 工作溫度范圍:- 40 C to + 150 C 安裝風格:SMD/SMT 封裝 / 箱體:HPSO-8 封裝:Reel |
| INA138NA/250 | 制造商:Texas Instruments 功能描述:IC CURRENT SHUNT MONITOR |
| INA138NA/250 | 制造商:Texas Instruments 功能描述:Current Shunt Monitor IC |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。