What is open collector pull-up resistor?

What is open collector pull-up resistor?

Open collector outputs require a pull-up resistor (R in the image above) for the output to be able to properly “output high”. The pull-up resistor is connected between the output pin and the output voltage (Vcc in the image above) that is desired for a high state.

What is an open collector comparator?

Op-amp window comparators are a type of voltage comparator circuit which uses two op-amp comparators to produce a two-state output that indicates whether or not the input voltage is within a particular range or window of values by using two reference voltages. An upper reference voltage and a lower reference voltage.

Why are comparators open collector?

The main reason for using open-collector is so that several comparators can have their output connected together in a wired OR gate. All the open collectors can be tied together to a single resistor without any conflicts between comparators.

How do you use open collector output?

With open collector output, you simply cannot just connect the output device to the pin and then to ground. Open collector does not work that way. It must have positive voltage and then the load and the negative or ground side of the load connects to the output.

What is open collector TTL?

In the open collector TTL gate, the output stage does not have the active pull-up transistor i.e. Q3 and the output is taken at the collector of transistor Q4. In order to generate required HIGH and LOW states, an external pull-up resistor is connected to +Vcc from the collector of Q4.

What is meant by open collector?

An open collector is a common type of output found on many integrated circuits (IC), which behaves like a switch that is either connected to ground or disconnected.

What is push-pull output in electronics?

A push–pull amplifier is a type of electronic circuit that uses a pair of active devices that alternately supply current to, or absorb current from, a connected load. This kind of amplifier can enhance both the load capacity and switching speed.

What is the purpose of using an open collector comparator?

The main reason for using open-collector is so that several comparators can have their output connected together in a wired OR gate. All the open collectors can be tied together to a single resistor without any conflicts between comparators. This would not have been easy to do when your comparator has also the capability…

What is an open collector output?

An open collector output is simple and flexible but relatively slow compared to other logic outputs. Since most comparators are slow, it is OK to use open collector outputs for them. Fast comparators may have other types of outputs. For example, the extremely fast ADCMP580 has ECL outputs.

What is the purpose of using an open-collector?

The main reason for using open-collector is so that several comparators can have their output connected together in a wired OR gate. All the open collectors can be tied together to a single resistor without any conflicts between comparators.

Can all the open collectors be tied together with one resistor?

All the open collectors can be tied together to a single resistor without any conflicts between comparators. This would not have been easy to do when your comparator has also the capability to source current at its output.