| 摘要 |
PURPOSE:To obtain a cross coil type meter driving circuit which has small deviation from linearity by generating a sine component voltage and a cosine component voltages which are approximated to a trapezoid having two gradients at oblique side parts. CONSTITUTION:The output of a reference voltage generating circuit 2 is inputted to a two-voltage generating circuit and also inputted to an output circuit 8 and selective inverting circuits 4 and 5. Two outputs of the sine component voltage Vsin and cosine component voltage Vcos of the circuit 1 are inputted to an output circuit 6 and the circuit 5, and an output circuit 7 and the circuit 4 respectively. The circuits 4 and 5 invert the signals selectively so that the absolute values of the sine component voltage and cosine component voltage can be compared with each other, and their outputs are inputted to a comparing circuit 3 for switching two gradients of oblique side parts of the trapezoid, and the output of the circuit 3 is inputted to the circuit 1. Then the outputs of the circuits 6, and 7 and 8 are inputted to two coils of the cross type meter 9, which is driven.
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