Uploaded February 2025 | Updated September 2026, 3 weeks ago
*_In this video, the internal circuit and the working of TTL Open Collector gates and Tri-State TTL gates are explained._*
*_The video also explains, why TTL Totem Pole outputs cannot be connected together and how open collector gates can perform wired AND logic._*
_The following topics are covered in the video:_
0:00 Advantage of Totem-pole output stage in TTL gates
1:18 Why TTL Totem Pole outputs can not be connected together
3:39 TTL Open-Collector gates
9:55 Tri-state TTL Inverter Circuit and its Working
_The link for the other useful topics mentioned in this video:_
*1) Wired AND Logic:*
youtu.be/huj-pLr0-3w?si=Mbx3KAn9JdS4U1RQ
*2) Pull-up Resistors:*
youtu.be/V0GeJPqzqsI?si=Gz1FAkc-vxCm9LTp
*3) TTL Logic:*
youtu.be/I74vWLGif_o?si=w0aKRnQUvUx2MlyC
*4) TTL NAND gate and NOR gates:*
youtu.be/sDn2hi5ndCA?si=boNXjhF_b4Diq-_F
*Open-Collector TTL gates:*
In open-collector TTL gates, the collector terminal of the output transistor is kept open and the output is taken through the collector terminal. For reliable operation of the logic gate and to ensure proper logic level, often open collector gates are used with external pull-up resistor. Because of this external passive pull-up, it is possible to connect the output of the open collector gates together and hence it is possible to perform the wired AND logic.
The disadvantage of open collector gate is that, the switching speed of these gate is lower than the TTL gates with Totem-pole outputs.
*Tri-State TTL gates:*
In Tri-state TTL gates, there is a one more input (Enable input) other than the conventional data inputs.
When Enable input is LOW, then output of the Tri-State gate is Hi-Impedance. And when Enable input is HIGH, then logic gate behaves as normal gate. And depending on the input combination, we get output.
In this video, the internal circuit and the working of the Tri-State TTL inverter is explained.
This video will be helpful to all the students of science and engineering in understanding the Open Collector TTL gates, why they can perform wired AND logic and the working and internal circuit of Tri-state TTL gates.
#allaboutelectronics
#digitalelectronics
#logicfamily
#ttllogic
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Music Credit: bensound.com
*_In this video, the internal circuit and the working of TTL Open Collector gates and Tri-State TTL gates are explained._*
*_The video also explains, why TTL Totem Pole outputs cannot be connected together and how open collector gates can perform wired AND logic._*
_The following topics are covered in the video:_
0:00 Advantage of Totem-pole output stage in TTL gates
1:18 Why TTL Totem Pole outputs can not be connected together
3:39 TTL Open-Collector gates
9:55 Tri-state TTL Inverter Circuit and its Working
_The link for the other useful topics mentioned in this video:_
*1) Wired AND Logic:*
youtu.be/huj-pLr0-3w?si=Mbx3KAn9JdS4U1RQ
*2) Pull-up Resistors:*
youtu.be/V0GeJPqzqsI?si=Gz1FAkc-vxCm9LTp
*3) TTL Logic:*
youtu.be/I74vWLGif_o?si=w0aKRnQUvUx2MlyC
*4) TTL NAND gate and NOR gates:*
youtu.be/sDn2hi5ndCA?si=boNXjhF_b4Diq-_F
*Open-Collector TTL gates:*
In open-collector TTL gates, the collector terminal of the output transistor is kept open and the output is taken through the collector terminal. For reliable operation of the logic gate and to ensure proper logic level, often open collector gates are used with external pull-up resistor. Because of this external passive pull-up, it is possible to connect the output of the open collector gates together and hence it is possible to perform the wired AND logic.
The disadvantage of open collector gate is that, the switching speed of these gate is lower than the TTL gates with Totem-pole outputs.
*Tri-State TTL gates:*
In Tri-state TTL gates, there is a one more input (Enable input) other than the conventional data inputs.
When Enable input is LOW, then output of the Tri-State gate is Hi-Impedance. And when Enable input is HIGH, then logic gate behaves as normal gate. And depending on the input combination, we get output.
In this video, the internal circuit and the working of the Tri-State TTL inverter is explained.
This video will be helpful to all the students of science and engineering in understanding the Open Collector TTL gates, why they can perform wired AND logic and the working and internal circuit of Tri-state TTL gates.
#allaboutelectronics
#digitalelectronics
#logicfamily
#ttllogic
Support the channel through membership program:
youtube.com/channel/UCBkOVp1Cqz4MR0LYR8vKpZg/join
--------------------------------------------------------------------------------------------------
Follow my second channel:
youtube.com/channel/UCGA2TO8ylVqFHpucwn_6Jlw
Follow me on WhatsApp channel:
whatsapp.com/channel/0029VaLeZrfAO7RDoKr7je0l
Follow me on Facebook:
facebook.com/ALLABOUTELECRONICS
Follow me on Instagram:
instagram.com/all_about.electronics
--------------------------------------------------------------------------------------------------
Music Credit: bensound.com
