| 摘要 |
PURPOSE:To enhance workability while reducing cost, by setting voltage by merely cutting a jumper wire in order to supply the voltage corresponding to printing heads classified by rank on the basis of the irregularity in the resistance values of the heads. CONSTITUTION:New, when non-stabilized voltage is applied to an input terminal 1, an error amplifier A compares the output voltage divided by resistors R1, R2 applied to the temnal 4 thereof and set voltage VR divided by a resistor net and applied to the terminal 5 thereof and, by the obtained error signal, the base voltage of a control transistor Tr is controlled. By this method, a signal is outputted to a terminal 3 so as to always supply objective voltage Vo to a printing head. In this embodiment, a set supply voltage is connected to a terminal 6 and, by merely cutting either one of a jumper wire JA or JB or cutting none of them, voltage corresponding to the heads of resistance value ranks A, B, C is supplied. Therefore, the labove of voltage adjustment is reduced. |
