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THREE-PHASE WAVEFORM MODE

7906 Group User’s Manual Rev.2.0

10-33

10.5 Three-phase waveform output fixation

In the three-phase waveform output, by setting of the U/V/W-phase output fix bit (bits 2 through 0 at address

A816) to “1,” the output level of each phase can be fixed. The output level to be fixed (positive phase) is set

by the U/V/W-phase fixed output’s polarity set bit (bits 2 through 0 at address A916); in the case of the

negative phase, the output level is fixed to the reversed level.

The U/V/W-phase output fix bit serves synchronously with a timer A3 interrupt request.

While the fixed level is output, be sure not to change the value of the U/V/W-phase fixed output’s polarity

set bit (bits 2 through 0 at address A916).

Figure 10.5.1 shows a triangular wave modulation output example using the U/V/W-phase output fix bit

(three-phase mode 1).

➀ By software, set the following bits:

• the U/V/W-phase output fix bit (bits 2 through 0 at address A816)

• the U/V/W-phase fixed output’s polarity set bit (bits 2 through 0 at address A916)

➁ The contents of the above bits become valid synchronously with the next timer A3 interrupt request, and

then, the output level of the positive waveform is fixed to the level which was set by the U/V/W-phase

fixed output’s polarity set bit. In the case of the negative phase, the output level is fixed to the reversed

level.

➂ Each of the positive and negative waveform outputs is not allowed to become “L” level from “H” level

until the reversed signal of the one-shot pulse output of the dead-time timer rises.

➃ The output fixation is also terminated synchronous with a timer A3 interrupt request.

7906 Datasheet(PDF) 238 Page - Renesas Technology Corp