| 摘要 |
PROBLEM TO BE SOLVED: To provide a slew rate output circuit, which maintains a slew rate function and reduces a delay time of an output waveform by switch controlling a value of a constant current which charges and discharges an input capacitance of an output transistor. SOLUTION: A delaying circuit D1 and a NAND gate G1 generate a signal Va , which becomes a low level only for a short fixed time T1 from the time when an input pulse signal Vin transits from a low level to a high level. Also, a delaying circuit D2 and a NOR gate G2 generate a signal Vb , which becomes a high level only for a short fixed time T2 from a point of time when the input pulse signal Vin , transits from the high level to the low level. The signal Va is connected to a P-channel transistor Q1 and a signal VD is connected to an N-channel transistor Q2 respectively. As a result, an output transistor Q0 is driven by the input pulse signal by way of a resistor R0 and by a drain of the P-channel transistor Q1 by way of a resistor R1 during a period T1 , by the input pulse signal Vin by way of a resistor R0 and by the drain of the N-channel transistor by way of a resistor R2 during a period of T2 , and only the input pulse signal Vin by way of the resistor R0 during other periods respectively. |
