| 摘要 |
PURPOSE:To lighten the load of a drive circuit for feeding a switching voltage by employing a transistor as switching element in place of a diode. CONSTITUTION:When the switching voltage VS to a switching voltage supply terminal 8 is set at the H level, a transistor 12 is held OFF to compare an input signal V1 with an input signal V2. When the switching voltage V3 is set at the L level, the base of a transistor 1 is clamped at VEB and held OFF while a transistor 2 is held ON to turn the output voltage VO to VCC-IOR1. VEB is an emitter base forward voltage drop of the transistor 12. Current of (V1-VEB)/R1 flows through the transistor 12 while the current demanded for a switching voltage source connected to the base is 1/hFE. The hFE is the current amplification factor of the transistor 12. |
