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likephysics
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Just wondering how would one design a comparator using just discrete BJTs.
likephysics said:Emitter coupled pair like the one in attachment?
I've been playing with this since yesterday. How do you fix the gain of this ckt.
In the ckt, how do I overcome the min Vbe requirement of Q1,Q2.
For a TTL output comparator a BJT configured as a CE amplifier with Vcc=5v would work?
I just need something that works and also simple enough to understand.
Ok I modified your circuit to make about the simplest "comparator" possible out of a few discrete components.likephysics said:huh. Here it is.
The most important factors to consider when selecting BJTs for a comparator design are their current gain (hFE) and speed. BJTs with a high current gain will provide better accuracy, while faster BJTs will result in a faster response time. It is also important to ensure that the BJTs have a low offset voltage to minimize errors in the comparator's output.
Using discrete BJTs allows for greater flexibility and customization in the design. Discrete BJTs can be selected and configured to meet specific requirements and can also handle higher voltages and currents than integrated circuits. Additionally, using discrete BJTs can be more cost-effective for certain applications.
Stability in a comparator design can be achieved by adding external compensation components such as resistors and capacitors. These components can help to minimize oscillations and prevent the comparator from latching on to noise or other unwanted signals.
Yes, you can use different types of BJTs in your comparator design, as long as they have similar characteristics and are operated within their specified parameters. It is important to ensure that the BJTs have similar current gain, speed, and characteristics such as breakdown voltage to maintain accuracy in the comparator's output.
To improve the performance of your comparator design, you can use BJTs with lower noise levels, higher current gain, and faster response times. Additionally, careful selection and placement of external components such as resistors and capacitors can also help to improve the overall performance of the comparator.