Datasheet

G
0.6V
Reference
Comparator
OUT
CMP
IN
CMP
OUT
RESET
V
IN-
V
IN+
INA200
(G=20)
GND
V+
2
3
4
6
5
7
8
1
R
PULL-UP
4.7kW
Latch
Transparent/Reset
C
BYPASS
0.01 Fm
R
SHUNT
3mW
LoadSupply
-18Vto+80V
Load
5VSupply
R
1
R
2
INA200
INA201
INA202
SBOS374C –NOVEMBER 2006–REVISED OCTOBER 2010 www.ti.com
APPLICATIONS INFORMATION
BASIC CONNECTIONS ACCURACY VARIATIONS AS A RESULT OF
V
SENSE
AND COMMON-MODE VOLTAGE
Figure 26 shows the basic connections of the
INA200, INA201, and INA202. The input pins, V
IN+
The accuracy of the INA200, INA201, and INA202
and V
IN–
, should be connected as closely as possible current shunt monitors is a function of two main
to the shunt resistor to minimize any resistance in variables: V
SENSE
(V
IN+
– V
IN–
) and common-mode
series with the shunt resistance. voltage, V
CM
, relative to the supply voltage, V
S
. V
CM
is
expressed as (V
IN+
+ V
IN–
)/2; however, in practice,
Power-supply bypass capacitors are required for
V
CM
is seen as the voltage at V
IN+
because the
stability. Applications with noisy or high-impedance
voltage drop across V
SENSE
is usually small.
power supplies may require additional decoupling
capacitors to reject power-supply noise. Connect This section addresses the accuracy of these specific
bypass capacitors close to the device pins. operating regions:
• Normal Case 1: V
SENSE
≥ 20mV, V
CM
≥ V
S
POWER SUPPLY
• Normal Case 2: V
SENSE
≥ 20mV, V
CM
< V
S
The input circuitry of the INA200, INA201, and
• Low V
SENSE
Case 1: V
SENSE
< 20mV, –16V ≤ V
CM
INA202 can accurately measure beyond the
< 0
power-supply voltage, V+. For example, the V+ power
• Low V
SENSE
Case 2: V
SENSE
< 20mV, 0V ≤ V
CM
≤
supply can be 5V, whereas the load power-supply
V
S
voltage is up to +80V. The output voltage range of
• Low V
SENSE
Case 3: V
SENSE
< 20mV, V
S
< V
CM
≤
the OUT terminal, however, is limited by the voltages
80V
on the power-supply pin.
Figure 26. INA200 Basic Connections
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Product Folder Link(s): INA200 INA201 INA202