AN1625 STMicroelectronics, AN1625 Datasheet - Page 2

• Manufacturer Part Number: AN1625
• Description: L6235 THREE PHASE BRUSHLESS DC MOTOR DRIVER
• Manufacturer: STMicroelectronics

AN1625 APPLICATION NOTE
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INTRODUCTION ................................................................................................................................1
DESIGNING AN APPLICATION WITH L6235 ...................................................................................3
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
2.10 DIAG pin.................................................................................................................................11
2.11 Programmable off-time Monostable .......................................................................................12
2.12
2.13 Power Management ...............................................................................................................20
2.14
2.15
2.16
APPLICATION EXAMPLE................................................................................................................32
APPENDIX - EVALUATION BOARDS .............................................................................................34
4.1
4.2
REFERENCES.................................................................................................................................39
2.11.1 Off-time Selection and minimum on-time ........................................................................14
2.11.2 Slow Decay Mode ...........................................................................................................14
2.13.1 Maximum output current vs. selectable devices..............................................................20
2.13.2 Power Dissipation Formulae ...........................................................................................21
2.15.1 Static performance - Speed Regulation vs. Resistant Torque: .......................................28
2.15.2 Dynamic performance: ....................................................................................................29
2.15.3 Loop Stability: ..................................................................................................................30
2.15.4 Reference voltage ripple: ................................................................................................30
4.2.1 Important Notes ................................................................................................................36
Current Ratings ........................................................................................................................3
Voltage Ratings and Operating Range ....................................................................................3
Choosing the Bulk Capacitor....................................................................................................5
Layout Considerations .............................................................................................................5
Sensing Resistor ......................................................................................................................7
Charge pump external components .........................................................................................8
Sharing the Charge Pump Circuitry .........................................................................................9
Reference Voltage for PWM Current Control.........................................................................10
Input Logic pins ......................................................................................................................11
PractiSPIN..............................................................................................................................34
EVAL6235N ...........................................................................................................................35
Over Current Detection .........................................................................................................16
The decoding logic ................................................................................................................24
Tacho Output and Speed Loop .............................................................................................25
Brake.....................................................................................................................................31
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