TSC103 STMicroelectronics, TSC103 Datasheet - Page 19

• Manufacturer Part Number: TSC103
• Description: High voltage, high side current sense amplifier
• Manufacturer: STMicroelectronics

Specifications of TSC103

• Wide Common-mode Operating Range: 2.9 to 70 V in single-supply configuration, -2.1 to 65 V in dual-supply configuration
• Wide Common-mode Surviving Range: -16 to 75 V (reversed battery and load-dump conditions)
• Supply Voltage Range: 2.7 to 5.5 V in single-supply configuration
• Low Current Consumption: ICCmax = 360 μA
• Pin Selectable Gain: 20 V/V, 25 V/V, 50 V/V or 100 V/V

TSC103
7
Application information
The TSC103 can be used to measure current and to feed back the information to a
microcontroller.
Figure 22. Single-supply configuration 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 R
Therefore, the drop across R
If I
The I
negligible). Therefore, the voltage drop on the R
The voltage across the R
a gain equal to K2. Therefore V
or: V
Rg1
out
V
I
V
V
Rg1
Rg1
out
Rg1
Rg3
is the current flowing through R
= Av .R
current flows entirely into resistor R
= K1.K2.V
= V
= V
= R
Rg1
Rg1
Vp
Vp
TSC103
sense
sense
g3
sense
sense
.I
Rsense
Rsense
Vcc-
Vsense
Rg1
/R
= R
sense
.I
g1
across R
= (R
load
sense
Vm
Vm
Rg2
Rg2
= Av.V
g3
g3
g1
Iload
Iload
/R
.I
resistor is buffered to the Out pin by the voltage buffer, featuring
amplifier
so that the voltage drop across R
Sense
load
g1
sense
g1
Doc ID 16873 Rev 2
out
sense
is:
).V
Gnd
Rg3
. The amplifier’s input currents are negligible, therefore its
sense
can be expressed as:
m
. The amplifier's open-loop gain forces its non-inverting
with Av= K1.K2
g1
Common-mode voltage: 2.9 V to 70 V
= K1.V
, then I
Voltage
buffer
Vcc+
Vcc+
g3
K2
sense
Rg1
(the input bias current of the buffer is
g3
resistor can be calculated as follows.
is given by the formula:
with K1=R
SEL1
SEL1
SEL2
Out
sense
g1
g3
Vout
matches V
/R
resistor, causing a voltage
Application information
g1
.
GPIO1
GPIO2
sense
Vcc
Vcc
Gnd
µ Controller
ADC
exactly.
AM04517
19/26
5 V