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10 years, 6 months ago.
How to synchronize two PWM pins in LPC 1768
I need to control an inverter where it has six IGBTs where they are working according to the pwm signals provided by the mbed. To avoid short circuiting the output given by the inverter, when the top IGBT of one of the legs of the inverter turns on, the bottom IGBT should be turned off. That means I need to synchronize two pwm pins where when one is turned on, the other should be turned off. How can I accomplish this? Thank you for being attending to my question.
2 Answers
10 years, 6 months ago.
By default on the LPC1768 the PWM pins run in single edge mode: they all turn on at the same time, and turn off at different times.
You got dual edge mode you can enable by manually writing registers (might also be a library on the site for it), which enables you to change when the rising edge happens and when the falling edge in the period. However that costs 2 match registers: you can then only have 3 outputs on the LPC1768.
7 years, 6 months ago.
how can i change the direction of single edge PWM and dual edge PWM? Single edge pwm should starts with negative edge? according to rule single edge pwm starts with high but for my application it must starts with negative. can anybody help me on this