STEVAL-IHM012V1 STMicroelectronics, STEVAL-IHM012V1 Datasheet
STEVAL-IHM012V1
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STEVAL-IHM012V1 Summary of contents
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... STEVAL-IHM012V1 - Cordless drill evaluation board Introduction This document contains cordless drill evaluation board information, including jumper settings, load connection, and device and software features. This evaluation board implements a traditional design solution detailing how the Chopper circuit controls a brush DC motor with a microcontroller as a driver. The electronic driver with a Power MOSFET and microcontroller presented in this document is cost-effective and easy for designers to implement ...
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... Contents 1 Block diagram of a single switch Chopper . . . . . . . . . . . . . . . . . . . . . . . 4 1.1 Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Power MOSFET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.4 Freewheeling diode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 STEVAL-IHM012V1 evaluation board . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 Size optimization design procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 Application design procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1 Zener regulator circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2 Sensing resistor (R 4.3 Power MOSFET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5 Software ...
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... UM0291 List of figures Figure 1. Block diagram of a single switch Chopper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 2. STEVAL-IHM012V1 evaluation board picture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 3. Zener regulator circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 4. R versus drain pad area for DPACK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 THJ_PCB Figure 5. Option byte for STEVAL-IHM012V1 firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 6. Main programming flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 7. Flowchart of the pwm_ar_timer_12bit module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figure 8 ...
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Block diagram of a single switch Chopper 1 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 ...
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UM0291 In this evaluation board we have chosen the ST7FULTRALITE which is a very small and less expensive microcontroller available in DIP8, DFN8 and SO8 packages: ● Extended -40°C to 125°C temperature range ● Fast 10-bit ADC ● 8-bit timer ...
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... J1 and J2" Warning: With easy adjustments the STEVAL-IHM012V1 can drive DC brush motors 7 The maximum power range used on the evaluation board depends on the motor driven (maximum handling current) and relative Power MOSFET mounted on the board (see Section 4: Application design This evaluation board is set up to work with a 7 ...
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... UM0291 Figure 2. STEVAL-IHM012V1 evaluation board picture 3 Size optimization design procedure This demo board implements a general solution to drive a low voltage DC brush motor. The application is optimized for cordless hand tools (drill, saw, screwdriver). The size is small enough to be inserted directly in the tool To minimize the size of the board: ● ...
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Application design procedure 4 Application design procedure This evaluation board can be configured for different DC brush motors: 7 here we have an example of design procedure for 7 brush motor. If the user ...
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UM0291 So R will be: S Equation 3 For the 7.2 cordless drill (6 cells) we have chosen V 4.2 Sensing resistor (R The value of the sensing resistor must be chosen to guarantee the right power dissipation at the ...
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Application design procedure Where T = Ambient Temperature Total thermal resistance TH_TOT The total power dissipation will be: Equation 8 In the evaluation board the available copper area on PCB for heat dissipation is almost 2 400 ...
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... The option byte set in this project is shown in Figure 5. Option byte for STEVAL-IHM012V1 firmware Note: the overall code with the actual function is very small, almost 213 Byte. The firmware parameters are set for the 7.2 DC brush motor, if the designer wishes to change the motor he must change the firmware parameters in the file utility ...
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Software The working principle of using a Power MOSFET to drive DC brush motor is to change the duty cycle of the PWM control signal generated by the 12-bit autoreload timer (AT) inside the software. Note: Before downloading firmware in ...
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UM0291 5.2 pwm_ar_timer_12bit.c The AT timer in OF mode is used as the main time counter. This interrupt is handled in the AR_TIMER_OF_Interrupt routine in the pwm_ar_timer_12bit module. This module generates the PWM control signal to the frequency of 15 ...
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Field tests 6 Field tests We have plotted the PWM control signal (waveform in blue) and the current in the motor (waveform in black) when it runs in no load condition and in the blocked rotor condition. We have some ...
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... UM0291 7 Schematic Figure 12. STEVAL-IHM012V1 evaluation board schematic 8 Bill of material (BOM) Table 1. Bill of material Value / generic Index Qty Reference part number 1 3 C1,C2,C5 100 nF ± 100 pF ± µ ±10 DZ1 5 STPS5L25B J1,J2 Package SMD_0805 SMD_0805 SMD_0805 SMD_1206_12 LED SMD_1206_21 SMD DPAK ...
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... AN414: Controlling a brush DC motor with an ST6265 Microcontroller 16/18 Package CON1 FASTONF 10 pin strip header - ICC Con dual in line2.54 mm pitch SMD_DPAK SMD_0805 SMD_0805 10 kΩ VRES18 SMD_1206 SMD_0805 SMD_0805 SMD_0805 SMD_1206 SMD_0805 SMD_0805 SO8 UM0291 Manufacturer’s ordering code / Manufacturer orderable part number STMicroelectronics STD50NH02LT4 ST ST7FLITEUS5M6 ...
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UM0291 10 Revision history Table 2. Document revision history Date 19-Dec-2006 08-Jan-2007 25-Oct-2007 Revision 1 First issue 2 Figure 2 changed 3 Modified: Figure 5 and Revision history Changes Table 1 17/18 ...
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... Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...