| 摘要 |
PURPOSE:To completely evade a situation that an NPN bipolar transistor controlling a current setting falls into a saturated state by providing first and second bipolar transistors and N first type conductive MOS transistors respectively. CONSTITUTION:Corresponding to a reference current source control input terminal 51, switching current output terminals 52-1 and 52-2, current switching control signal input terminals 53-1 and 53-2, and a high potential power source voltage VDD and a low potential power source voltage VSS, this circuit is constituted of a current source 1, NPN bipolar transistors 2, (3-1) and (3-2) and N- channel MOS transistors 4, (5-1) and (5-2). By a level signal impressed to the switching control signal input terminal 53-1, an output current flowing through the switching current output terminal 52-1 can be controlled to switch. This also has a function controlling to switch the output current flowing through the switching current output terminal 52-2 by the level signal impressed to the current switching control input terminal 53-2. |
