| 摘要 |
PURPOSE:To adjust an irregularity in brightness of an LED by an irregularity in an output current characteristic in each integrated circuit at the inside of the integrated circuit by using an input signal from the outside and to omit an element resistance to be added at the outside by a method wherein a resistance element component which can be selected by an internal logic signal is constituted at a bulk part of a P-channel output transistor. CONSTITUTION:An LED 4 is connected to a drain of a P-channel output transistor 2; it is lighted up by an operation of the P-channel output transistor 2. In ladder resistance element parts 8a to 8c, a terminal function is formed by injecting a P<+> diffusion into a P<-> well; a resistance element is constituted of an island resistance inside the P<-> well. One resistance element terminal part out of 8a to 8c is selected by a selection signal from a decoder 5; it is connected to a bulk part of the P-channel output transistor 2. A back gate bias voltage is applied to the bulk part of the transistor 2; when this bias voltage is increased, a Vr of the output transistor can be increased. When the Vr is made variable, it is possible to control an output current characteristic. |
