What is a totem pole circuit?
Totem-pole output, also known as a push-pull output, is a type of electronic circuit and usually realized as a complementary pair of transistors. The High and Low level of the output are determined. The output of high level is 10 V max, low level is 0.5 V min.
Why is the TTL output circuitry called totem-pole?
The output circuitry of this particular gate is commonly referred to as “totem-pole,” because the two output transistors are stacked one above the other like figures on a totem pole. TTL gates equipped with totem-pole output circuitry are able to both source and sink load current.
When totem pole outputs are tied together?
SgtWookie. If you tie two totem-pole outputs together, they will “fight to the death” if they are set to different logic levels. You can use diodes from each output with a pull-up or pull-down resistor, depending on the logic you want.
What is wire ANDing?
A wired-AND operation ( English for wired AND ), rarely phantom ANDing called, is used in the digital circuitry when two or more outputs are connected together so that the circuit as an AND gate (engl. AND ) works. In contrast to the wired-OR logic, the output transistors are activated high-active.
What does it mean to have a totem pole driver?
A totem pole driver or output stage is a loose term used to mean that the output is driven actively in both the high and low directions. A totem pole output can be an NPN/PNP or N Channel/P Channel “complementary pair” or, as is the case in many TTL logic devices, two devices of the same polarity stacked on top of each other.
How is a totem pole used in a circuit?
Totem pole basically an output driver circuit use to convert one level of voltage into another level of voltage. For example, you want to drive gate of MOSFET with the help of microcontroller output pin.The microcontroller output pin is generating a square wave of voltage level 5 volt…
Which is the bipolar totem pole MOSFET driver?
Vdrv is a power supply. This is a bipolar emitter follower. It is a high current buffer capable of driving the high capacitance of the MOSFET gate. Buffer and gate current is limited by Rgate which also prevents ultrasonic gate oscillation.
Is the bottom of a totem pole an emitter follower?
They are BOTH emitter followers. The bottom transistor turns on just as much as the top does at the appropriate time. It is a matter of perspective. When OUT is high the upper transistor is on, conducts and pulls gate up. When OUT is low the lower transistor is on, conducts and pulls gate down. Vdrv is a power supply.