
AN2528/D
2
Standard Space Vector Modulation TPU Function Set (svmStd)
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can be used to generate one or more adjustable signals for a wide range of
uses, that are synchronized to the PWM, and track changes in the PWM period.
The Resolver Reference Signal for the svmStd function can be used to
generate one or more 50% duty-cycle adjustable signals that are also
synchronized to the PWM.The Fault Input for the svmStd function is a TPU
input function that sets all PWM outputs low when the input signal goes low.
See
Figure 1
.
Function Set Configuration
None of the TPU functions in the Standard Space Vector Modulation TPU
function set can be used separately. The svmStd_top and svmStd_bottom
functions have to be used together. The svmStd_top is used on 3 channels, the
svmStd_bottom on a further 3 channels, and within each phase, the function
svmStd_top has to be assigned on a lower TPU channel than the function
svmStd_bottom. This is illustrated in the examples in
Table 2
and
Table 3
. One
or more channels running a Synchronization Signal for svmStd as well as
Resolver Reference Signals for svmStd functions can be added to the
svmStd_top and svmStd_bottom functions. They can run with different settings
on each channel. The function Fault Input for svmStd can also be added to the
svmStd_top and svmStd_bottom functions. It is recommended to use it on
channel 15, and to select the hardware option that disables all TPU output pins
when the channel 15 input signal is low (DTPU bit = 1). This ensures that the
hardware reacts quickly to a pin fault state. Note that it is not only the PWM
channels, but all TPU output channels, including the synchronization signals,
that are disabled in this configuration.
Table 1
shows the configuration options and restrictions.
Table 2
and
Table 3
show two examples of configuration.
Table 1. svmStd TPU function set configuration options and restrictions
TPU function
Optional/
Mandatory
How many
channels
Assignable channels
svmStd_top
mandatory
3
any 3 channels, within each phase a
lower TPU channel than the same
phase svmStd_bottom
any 3 channels, within each phase a
higher TPU channel than the same
phase svmStd_top
any channels
any channels
any, recommended is 15 and DTPU bit
set
svmStd_bottom
mandatory
3
svmStd_sync
svmStd_res
optional
optional
1 or more
1 or more
svmStd_fault
optional
1
F
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n
.