STEVAL-IHM012V1 STMicroelectronics, STEVAL-IHM012V1 Datasheet - Page 4

• Manufacturer Part Number: STEVAL-IHM012V1
• Description: EVAL BRD POWER MOSFET/8PIN MCU
• Manufacturer: STMicroelectronics
• Type: Motor / Motion Controllers & Driversr

Specifications of STEVAL-IHM012V1

• Design Resources: STEVAL-IHM012V1 Gerber Files STEVAL-IHM012V1 Schematic STEVAL-IHM012V1 Bill of Materials
• Main Purpose: Power Management, Motor Control
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ST7FLITEUS5
• Primary Attributes: Brush DC Motors
• Secondary Attributes: DC Chopper
• Product: Power Management Modules
• Kit Application Type: Power Management - Motor Control
• Application Sub Type: BLDC Motor
• Kit Contents: Board
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: ST7FLiteUS5
• Other names: 497-5861

Block diagram of a single switch Chopper
1
1.1
4/18
Block diagram of a single switch Chopper
Brush DC motors can be driven in voltage mode since the motor speed is proportional to the
supply voltage. The chopper is driven by a high frequency PWM signal. Controlling the
PWM duty cycle is equivalent to controlling the motor voltage, which in turn adjusts directly
the motor speed.
A typical block diagram of a DC single switch Chopper is shown in
Figure 1.
Controller
We use a microcontroller to have a flexible controller and to implement the control algorithm
because an analog IC's functionality is tied to its application and the designer is limited to
fixed device functions. Thus we generate the PWM signal and implement some safety
protections.
Main features implemented:
●
●
●
DC motor speed regulation system. Through the pot you can change the duty cycle of a
PWM signal at 15 kHz:
–
–
Battery voltage check. There are 3 states managed by the controller through the
reading Level Battery:
–
–
–
High current protection - Torque limitation. When the current of the motor reaches the
maximum handling current (Imax) the Controller disables the PWM output regardless of
the pot position. In this case the LED turns on. As soon as the current becomes less
than Imax, the control switches back to the user and the LED turns off.
POT zero position ' NO PWM signal '
POT increase position ' Duty Cycle: 13 ÷ 100%
Charged LED turn off
Low LED Slow flashing (warning): threshold 90% of the nominal voltage
Discharged Fast flashing (the motor cannot work): threshold 88% of the nominal
voltage
Block diagram of a single switch Chopper
Figure
1.
UM0291