If either or both of the inputs is high, the output is driven low. In this alternative way to achieve NOR logic, only one transistor is used with the two inputs tied to its base through resistors. In the actual circuit, an OUTPUT HIGH of 9V(Vcc) may or may not be attainable due to component limitations but ill try to make it close. When the base-emitter diode is turned on enough to be driven into saturation, the collector voltage with respect to the emitter may be near zero and can be used to construct gates for the TTL logic family. The use of transistors for the construction of logic gates depends upon their utility as fast switches. For the NOR logic, the transistors are in parallel with the output above them so that if either or both of the inputs are high, the output is driven low. At the moment iam running ESPHome on a WeMos D1, with a connected NPN inductive sensor. When the base-emitter diode is turned on enough to be driven into saturation, the collector voltage with respect to the emitter may be near zero and can be used to construct gates for the TTL logic family. The sensor Vcc is connected to the NodeMCU +3. The output is high unless both A and B inputs are high, in which case the output is taken down close to ground potential. 2 When the supply voltage in a system is switched off (V CC 0 V), the VCC pin of a logic device is short circuited to ground via the other components in the system. circuits wherein logic gates employ diodes in the input stage and bipolar junction transistors at the. For the NAND logic, the transistors are in series, but the output is above them. The meaning of input voltage tolerance is fairly obvious, but the meaning of output voltage tolerance requires some explanation. The use of transistors for the construction of logic gates depends upon their utility as fast switches. example, if a device has a VDD of 2.5 V and can accept inputs equal to 3.3 V and can withstand 3.3 V on its outputs, the 2.5 V device is called 3.3 V tolerant. For the OR logic, the transistors are in parallel and the output is driven high if either of the transistors is conducting. HyperPhysics***** Electricity and magnetism For the AND logic, the transistors are in series and both transistors must be in the conducting state to drive the output high.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |