| 摘要 |
<p>PURPOSE:To reduce the number of a driver and to save power consumption by so setting the connecting direction of a rectifier as to conduct a current only in one direction at the time of conducting current to first and second opening/closing elements at a heat generating resistor. CONSTITUTION:R1-R2048 are heat generating resistors of 2048 elements, and a common power supply line C is divided into 22. Switching circuits SW1, SW2 selectively connect the positive electrode of a DC power source E to the lines C1, C2 to input control signals S1, S2. When the signal S1 is a 'L' level and S2 is a 'H' level, i.e., only a transistor TR2 is turned ON, a voltage is applied from the power source E to the line C2. Accordingly, if arbitrary driving transistor tr1, tr2,..., tr44 of 64-bit driver IC1 are, for example, turned ON, a current flows to corresponding odd number resistors R1, R3,..., R127. Even if a current tends to flow to even number resistor R2n connected to the transistor trn turned ON, it is blocked by a diode D2n.</p> |
