STR750-MCKIT STMicroelectronics, STR750-MCKIT Datasheet - Page 6

• Manufacturer Part Number: STR750-MCKIT
• Description: Power Management Modules & Development Tools Compete motr control starter kit
• Manufacturer: STMicroelectronics
• Type: Motor / Motion Controllers & Driversr

Specifications of STR750-MCKIT

• Input Voltage: 18 V to 35 V
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Operational amplifier configuration
6/21
The op-amp is used in follower mode with a gain set by resistors r and R.
The relation between the input signal e and the signal v on the positive input of the follower
is:
where k =(1/r1+1/r2+1/r3)
The resistor values implemented on the MB549B board are:
and
Therefore, the gain is:
G = 6.4
The response of the op-amp is represented in
Figure 4.
With these settings, the output voltage of the op-amp is equal to 1.94V for a nil current.
The peak current that can be measured in this configuration is:
G = s / v = (R + r)/r
v = (U/(k*r3) + e/(k*r1))
R=5400Ω \ r=1000Ω \ r1=660Ω \ r2=560Ω \ r3=4700Ω
U=5V
+/- 5A for R_shunt = 0.1ohms
+/- 2.3A for R_shunt = 0.22 ohms
-0.6
Voltage response in three-shunt configuration
-0.4
-0.2
3.500
3.000
2.500
2.000
1.500
1.000
0.500
0.000
Op_Amp Output
V shunt
0
Figure
0.2
4.
0.4
0.6
Series2
UM0379