| 摘要 |
PURPOSE:To obtain a PWM signal by employing data of each pulse width in zone of 60 deg. or 90 deg., the initial value of the output pattern and two tables for designating variable bits, and using a preset counter, thereby controlling it. CONSTITUTION:When a motor M is variably controlled by an inverter INV, a CPU11, a memory 12, a counter 13 and a preset latch circuit 14 are coupled via a bus 10. Data of each pulse in a zone of 60 deg. or 90 deg., the initial value of the output pattern, and a table for designating variable bit are stored in the memory 12, an interrupt counter C1 is triggered by the counting up of a base counter C2, the CPU 11 is interrupted to start a calculation, the content of a preset latch circuit 14 is shifted via the counting up of a delay counter C3 to an output latch circuit 15, thereby obtaining a PWM signal. Accordingly, the configuration can be simplified, thereby enabling to perform a PWM control in a wide range. |
