AN2524 Freescale Semiconductor / Motorola, AN2524 Datasheet
AN2524
Related parts for AN2524
AN2524 Summary of contents
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... Freescale Semiconductor, Inc. Application Note AN2524/D Rev. 0, 5/2003 DC Motor with Dead-Time Correction TPU Function Set (DCmDt) By Milan Brejl, Ph.D. Functional Overview The DC Motor with Dead-Time Correction (DCmDt) TPU function set extends the functionality of the DC Motor TPU function set (DCm) by incorporating the dead-time correction technique. Apart from this, its functionality is the same in all other aspects ...
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... Freescale Semiconductor, Inc. AN2524/D Positive current Positive current - 50% PWM - 50% PWM (Q2) (Q2) PWM period PWM period center-time center-time DT DT SW1 SW1 SW2 SW2 DT DT SW3 SW3 SW4 SW4 motor motor voltage voltage Negative current - 50% PWM (Q3) PWM period center-time DT SW1 SW2 DT SW3 SW4 ...
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... For More Information On This Product, DC Motor with Dead-Time Correction (DCmDt) Synchronization Signal for DC Motor with Dead-Time Correction (DCmDt_sync) Resolver Reference Signal for DC Motor with Dead-Time Correction (DCmDt_res) Fault Input for DC Motor with Dead-Time Correction (DCmDt_fault) Go to: www.freescale.com AN2524/D Function Set Configuration Figure 1. 3 ...
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... Freescale Semiconductor, Inc. AN2524/D Table 1 Table 1. DCmDt TPU function set configuration options and restrictions TPU function DCmDt DCmDt_sync DCmDt_res DCmDt_fault Table 2 Table 3 TPU function 4 DC Motor with Dead-Time Correction TPU Function Set (DCmDt) shows the configuration options and restrictions. Optional/ How many ...
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... Synchronization Signal or a Resolver Reference Signal channel is used, wait until the HSR bits are cleared to indicate that initialization of the PWM channels has completed and – assign a priority to the DCmDt_sync or DCmDt_res channel to enable its initialization Go to: www.freescale.com AN2524/D Function Set Configuration 5 ...
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... Freescale Semiconductor, Inc. AN2524/D Detailed Function Description DC Motor with Dead- The DCmDt TPU function generates a 4-channel, 2-phase unipolar-switched Time Correction center-aligned PWM signal, with dead-time between the top and bottom (DCmDt) channels. In order to charge the bootstrap transistors, the PWM signals start to run 1 ...
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... DT 2 SW1 center _ time A LH SW2 center _ time B HL SW3 center _ time C LH SW4 center _ time to: www.freescale.com AN2524/D Detailed Function Description , SW3 and SW4 are calculated Negative current (current = center _ time A ...
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... Freescale Semiconductor, Inc. AN2524/D Host Interface 3 2 Channel 8 DC Motor with Dead-Time Correction TPU Function Set (DCmDt) Written By CPU Written By TPU Table 4. DCmDt Control Bits Name 1 0 Channel Function Select 1 0 Channel Priority 1 0 Host Service Bits (HSR Host Sequence Bits (HSQ) ...
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... Table 5. DCmDt Parameter RAM Parameter sync_presc_addr to: www.freescale.com AN2524/D Detailed Function Description LHtime_2 HLtime_2 T_copy center_time DT MPW LHtime_3 HLtime_3 L other_ch_3 current LHtime_4 HLtime_4 ...
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... Freescale Semiconductor, Inc. AN2524/D dc current T DT MPW sync_presc_addr fault_pinstate Other parameters are just for TPU function inner use. Performance Execution times do not include the time slot transition time (TST = IMB clocks Motor with Dead-Time Correction TPU Function Set (DCmDt) Table 6 ...
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... DC Motor with Dead-Time Correction TPU Function Set (DCmDt) For More Information On This Product, C20 Figure 4. DCmDt timing C1 C2 C10 C20 LH HL Figure 5. DCmDt state diagram Go to: www.freescale.com AN2524/D Detailed Function Description dc < center-time C10 C20 HL STOP HSR = 11 11 ...
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... Freescale Semiconductor, Inc. AN2524/D Minimum Pulse Width The TPU cannot generate PWM signals with duty cycle ratios very close 100%. This is the case when the dc value is close –1. The minimum pulse width that the TPU can be guaranteed to generate correctly is determined by the TPU function itself and by the activity on the other channels ...
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... For More Information On This Product, LH C10 MPW DT DT C10 LH Figure 7. Worst case timing – case two Figure 6 the MPW is 28 IMB clock cycles – DT. According to the MPW is 16 IMB clock cycles. In summary the MPW parameter Go to: www.freescale.com AN2524/D Detailed Function Description Figure 6 or Figure 7. 13 ...
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... Freescale Semiconductor, Inc. AN2524/D You can also use the Worst-Case Latency (WCL) that is automatically calculated by the MPC500_Quick_Start Graphical Configuration Tool. It can serve as a good approximation of MPW. The calculated WCL is always longer than the real-case is. Let the WCL be calculated after the configuration of the TPU channels and then find the longest WCL value within all the DCmDt PWM channels ...
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... Parameter to: www.freescale.com AN2524/D Detailed Function Description Written by both CPU and TPU Not Used Options DCmDt_sync function number (Assigned during assembly the DPTRAM code from library TPU functions) 00 – Channel Disabled 01 – ...
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... Freescale Semiconductor, Inc. AN2524/D Parameter move pw prescaler presc_copy Other parameters are just for TPU function inner use. Performance There is one limitation. The absolute value of parameter move has to be less then a quarter of the PWM period T. NOTE: Execution times do not include the time slot transition time (TST = IMB ...
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... PWM period center time of a number of TCR1 TPU cycles. MOTOROLA DC Motor with Dead-Time Correction TPU Function Set (DCmDt) For More Information On This Product center_time center_time T T Figure 9. DCmDt_sync timing to: www.freescale.com AN2524/D Detailed Function Description center_time center_time ...
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... Freescale Semiconductor, Inc. AN2524/D move > 0 prescaler = 1 move < 0 prescaler = 2 Synchronized Change The DCmDt_res TPU function can inherit the Synchronization Signal prescaler of PWM Prescaler that is synchronously changed with PWM prescaler. Write the synchronization And Resolver signals presc_copy parameter address to the presc_addr parameter to enable Reference Signals this mechanism ...
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... Parameter to: www.freescale.com AN2524/D Detailed Function Description Written by both CPU and TPU Not Used Options DCmDt_res function number (Assigned during assembly the DPTRAM code from library TPU functions) 00 – Channel Disabled 01 – ...
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... Freescale Semiconductor, Inc. AN2524/D Parameter move presc_addr prescaler Other parameters are just for TPU function inner use. Performance There is one limitation. The absolute value of parameter move has to be less than a quarter of the PWM period T. NOTE: Execution times do not include the time slot transition time (TST = IMB ...
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... The parameter is placed on the SW1 channel to keep the fault channel parameter space free. MOTOROLA DC Motor with Dead-Time Correction TPU Function Set (DCmDt) For More Information On This Product, S3 center_time T Figure 12. DCmDt_res timing S3 Figure 13. DCmDt_res state diagram Go to: www.freescale.com AN2524/D Detailed Function Description S1 center_time T 21 ...
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... Freescale Semiconductor, Inc. AN2524/D Host Interface 3 2 TPU function DCmDt_fault generates an interrupt when a high to low transition appears. Channel 22 DC Motor with Dead-Time Correction TPU Function Set (DCmDt) Written By CPU Written By TPU Table 16. DCmDt_fault Control Bits Name 1 0 Channel Function Select 1 0 Channel Priority ...
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... Parameters written by TPU Table 19. DCmDt_fault State Statistics State Max IMB Clock Cycles INIT FAULT 32 NO_FAULT Figure 14. DCmDt_fault timing FAULT Figure 15. DCmDt_fault state diagram Go to: www.freescale.com AN2524/D Detailed Function Description Description State of fault pin: 0 ... low 1 ... high RAM Accesses by TPU FAULT ...
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... MOTOROLA and the Stylized M Logo are registered in the US Patent and Trademark Office. All other product or service names are the property of their respective owners. Motorola, Inc Equal Opportunity/Affirmative Action Employer. © Motorola Inc. 2003 AN2524/D Rev. 0 5/2003 For More Information On This Product, ...