摘要 |
PURPOSE:To execute a color display, by using a dichromatic light emission diode, also generating an oscillating state by a capacitor, and dividing a drop state of supply voltage into 3 stages of a normal value, an availabe threshold value and an unavailable value. CONSTITUTION:Voltage V2 corresponding to a value of voltage of a battery B from a voltage dividing point of resistors R4 and R5 is inputted to a comparator U1 together with an output V1 of a constant-voltage circuit consisting of resistors R1, R2 and R3, and a Zener diode Z, and saturation output voltage V3 of this comparator U1 is inputted to a comparator U2. When the voltage of the battery B is within a normal range, a green light emitting element Gr of a light emission diode LED emits light, and when it is within an unavailable range, a red light emitting element Re emits light. Also, when it is within an available lower limit threshold range, a system containing the comparators U1, U2 and a capacitor C oscillates, and the red color and the green color emit light alternately. As a result, a light emission color of the light emission diode LED becomes yellow corresponding to an intermediate color of red and green. |