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CTR=0
CTR=CMPB
X
EN
SyncOut
Phase reg
Ext SyncIn
(optional)
EPWM1A
EPWM1B
SyncOut
Phase reg
CTR=CMPB
CTR=0
X
EN
EPWM2B
EPWM2A
Slave
Master
SyncIn
SyncIn
1
2
Φ
=0
°
Φ
=0
°
3.3
Controlling Multiple Buck Converters With Independent Frequencies
Controlling Multiple Buck Converters With Independent Frequencies
Figure 3-2. EPWM1 Configured as a Typical Master, EPWM2 Configured as a Slave
One of the simplest power converter topologies is the buck. A single ePWM module configured as a
master can control two buck stages with the same PWM frequency. If independent frequency control is
required for each buck converter, then one ePWM module must be allocated for each converter stage.
master can control two buck stages with the same PWM frequency. If independent frequency control is
required for each buck converter, then one ePWM module must be allocated for each converter stage.
shows four buck stages, each running at independent frequencies. In this case, all four ePWM
modules are configured as Masters and no synchronization is used.
shows the waveforms
generated by the setup shown in
; note that only three waveforms are shown, although there
are four stages.
SPRU791D – November 2004 – Revised October 2007
Applications to Power Topologies
71