TSC101 STMicroelectronics, TSC101 Datasheet - Page 14

• Manufacturer Part Number: TSC101
• Description: High side current sense amplifier
• Manufacturer: STMicroelectronics

Specifications of TSC101

• Wide Common-mode Operating Range: 2.8 to 30 V
• Wide Common-mode Surviving Range: -0.3 to 60 V (load-dump)
• Wide Supply Voltage Range: 4 to 24 V
• Low Current Consumption: ICCmax = 300 μA
• Internally Fixed Gain: 20 V/V, 50 V/V or 100 V/V

Application information
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Application information
The TSC101 can be used to measure current and to feed back the information to a
microcontroller, as shown in
Figure 23. Typical application schematic
The current from the supply flows to the load through the R
drop equal to V
inverting input voltage is equal to V
input to the same voltage as the inverting input. As a consequence, the amplifier adjusts
current flowing through Rg1 so that the voltage drop across Rg1 exactly matches V
Therefore, the drop across Rg1 is: V
If I
The I
negligible). Therefore, the voltage drop on the R
Because the voltage across the R
expressed as:
The resistor ratio R
to 100V/V for TSC101C.
The R
because they define the full scale output range of your application. Therefore, they must be
selected carefully.
Rg1
V
V
Rg1
out
sense
Rg3
is the current flowing through Rg1, then I
=(R
current flows entirely into resistor R
=R
resistor and the R
g3
g3
/R
.I
sense
Rg1
g1
).V
g3
=(R
across R
/R
sense
g3
g1
/R
is internally set to 20V/V for TSC101A, to 50V/V for TSC101B and
or V
g1
Figure
).V
g3
sense
Doc ID 13313 Rev 3
out
/R
sense
=(R
g3
g1
. The amplifier input currents are negligible, therefore its
m
23.
. The amplifier's open-loop gain forces its non-inverting
Rg1
resistor is buffered to the Out pin, V
resistor ratio (equal to A
g3
/R
=V
g1)
sense
.R
g3
sense
(the input bias current of the buffer is
Rg1
=R
g3
sense
resistor can be calculated as follows:
is given by the formula: I
.I
load
.I
load
sense
v
) are important parameters
resistor causing a voltage
out
can be
Rg1
=V
sense
sense
TSC101
/Rg1
.