0
Open collector output is normally used in logic circuits and can be viewed as a common emitter configuration for a BJT transistor and normally of type NPN. A typical common emitter configuration requires the emitter to be connected to the ground and a resistor Rc from Vcc to the collector. When the transistor becomes forward biased, the collector will pulled the voltage across the resistor down, from approximately Vcc down to almost 0V, normally in the order of 0.1V at the collector.
We can see that the output at the collector will swing between Vcc and ground. In open collector outputs the collector resistor Rc and Vcc have been left out. This enables the engineer to use any voltage and any pull-up resistor that will meet the specifications of the output transistor.
Normally it is acceptable in logic circuits that multiple inputs may be connected to one output, but not multiple outputs to one input due to the nature of the active outputs. With open collectors however multiple outputs may be connected to one input without damaging the device.
Low state will result in a lower impedance than a high state since the high state is obtained by current flowing from Vcc through the pull-up resistor Rc.
Open collector can be used to convert 5V logic to 8V or 12V logic or down to 3.3V since the logic high will be determined by the external supply to the pull up resistor.
Open collector also prevents component failure during output short-circuit or over-current. If an open collector is short circuited to the ground, it will cause no harm to the device since all the current will be supplied via the Rc resistor. Short circuit to a +supply rail can however damage the device.
Open collector is not used that commonly anymore but many variations of the same concept can be found in modern electronics. For example: micro processor devices that employ a I2C (Inter-Integrated Circuit) communications interface make use of a open-drain lines.
It appears to work very much in the same fashion with pull-up resistors and all. Open drain is associated with MOSFET transistors instead of BJT's. In this example an I2C interface will fail if pull-up resistors are not used. Like open collector, open drain lines are also passive and does not provide any active high output of its own. The High output is supplied by Vcc via the Rc or Rp pull-up resistors. The open collector or open drain will pull the pull-up resistor voltage down to the ground to create a low impendence, low logic state.
Wiki User
∙ 13y ago
Add your answer:
Earn +20 pts
What component develops the output signal in a common emitter amplifier?
The voltage drop across the emitter-collector junction develops the output signal with the help of a resistor or two in series. The output is 'seen' at the collector.
What is the input current for common collector?
from the name itself the common collector has its collector terminal in common with both the input and output circuits of a transistor and the base current is chosen as the input current and the output current is the emitter current
What effect does an open diode have on the output voltage of a half wave rectifier and on a full wave rectifier?
An open diode will result in no output from a half wave rectifier, and an open diode will cut the output of a full wave rectifier in half.
What are the parameters of a transistor?
# parameter are usually the base current ib,collector current ic,emitter current ie,collector emitter voltagevce,base emitter voltagevbe,collector base voltagevcb which decide the operation &output of the transistor
Why you use pull up resistor in microcontroller 8051?
Some devices are internally either in the open drain or in the open collector configuration. So in order to create a closed path for the current the device is pulled up with a resistor to the supply.
What are the difference between open collector output and totem pole out put?
Totem-pole output: two transistors with opposite drive : - if T1 is open, T2 is closed >> so the output is Vcc or logical 1 - if T1 is closed, T2 is open >> so the output is GND or logical 0 Vcc | T1 | -----output | T2 | GND Open collector output: the output with one transistor, whom collector is on Vcc through a R resistor.
Difference between line driver and push pull circuit?
Line Driver A line driver is a sourcing output. When in the on state, a line driver will supply Vcc. In the off state, a line driver will float. Because of this, a sinking input is required for proper operation. Open Collector An open collector is a sinking output. In the off state, an open collector will supply a path to ground. When in the on state, an open collector will float. For proper operation, a sourcing input is required. Push-Pull A push-pull output is a combination of a line driver and an open collector. In the off state it will supply a path to ground and in the on state it will supply Vcc.
What does open collector mean?
Open collector output is normally used in logic circuits and can be viewed as a common emitter configuration for a BJT transistor and normally of type NPN. A typical common emitter configuration requires the emitter to be connected to the ground and a resistor Rc from Vcc to the collector. When the transistor becomes forward biased, the collector will pulled the voltage across the resistor down, from approximately Vcc down to almost 0V, normally in the order of 0.1V at the collector. We can see that the output at the collector will swing between Vcc and ground. In open collector outputs the collector resistor Rc and Vcc have been left out. This enables the engineer to use any voltage and any pull-up resistor that will meet the specifications of the output transistor. Normally it is acceptable in logic circuits that multiple inputs may be connected to one output, but not multiple outputs to one input due to the nature of the active outputs. With open collectors however multiple outputs may be connected to one input without damaging the device. Low state will result in a lower impedance than a high state since the high state is obtained by current flowing from Vcc through the pull-up resistor Rc. Open collector can be used to convert 5V logic to 8V or 12V logic or down to 3.3V since the logic high will be determined by the external supply to the pull up resistor. Open collector also prevents component failure during output short-circuit or over-current. If an open collector is short circuited to the ground, it will cause no harm to the device since all the current will be supplied via the Rc resistor. Short circuit to a +supply rail can however damage the device. Open collector is not used that commonly anymore but many variations of the same concept can be found in modern electronics. For example: micro processor devices that employ a I2C (Inter-Integrated Circuit) communications interface make use of a open-drain lines. It appears to work very much in the same fashion with pull-up resistors and all. Open drain is associated with MOSFET transistors instead of BJT's. In this example an I2C interface will fail if pull-up resistors are not used. Like open collector, open drain lines are also passive and does not provide any active high output of its own. The High output is supplied by Vcc via the Rc or Rp pull-up resistors. The open collector or open drain will pull the pull-up resistor voltage down to the ground to create a low impendence, low logic state.
What does collector mean?
Open collector output is normally used in logic circuits and can be viewed as a common emitter configuration for a BJT transistor and normally of type NPN. A typical common emitter configuration requires the emitter to be connected to the ground and a resistor Rc from Vcc to the collector. When the transistor becomes forward biased, the collector will pulled the voltage across the resistor down, from approximately Vcc down to almost 0V, normally in the order of 0.1V at the collector. We can see that the output at the collector will swing between Vcc and ground. In open collector outputs the collector resistor Rc and Vcc have been left out. This enables the engineer to use any voltage and any pull-up resistor that will meet the specifications of the output transistor. Normally it is acceptable in logic circuits that multiple inputs may be connected to one output, but not multiple outputs to one input due to the nature of the active outputs. With open collectors however multiple outputs may be connected to one input without damaging the device. Low state will result in a lower impedance than a high state since the high state is obtained by current flowing from Vcc through the pull-up resistor Rc. Open collector can be used to convert 5V logic to 8V or 12V logic or down to 3.3V since the logic high will be determined by the external supply to the pull up resistor. Open collector also prevents component failure during output short-circuit or over-current. If an open collector is short circuited to the ground, it will cause no harm to the device since all the current will be supplied via the Rc resistor. Short circuit to a +supply rail can however damage the device. Open collector is not used that commonly anymore but many variations of the same concept can be found in modern electronics. For example: micro processor devices that employ a I2C (Inter-Integrated Circuit) communications interface make use of a open-drain lines. It appears to work very much in the same fashion with pull-up resistors and all. Open drain is associated with MOSFET transistors instead of BJT's. In this example an I2C interface will fail if pull-up resistors are not used. Like open collector, open drain lines are also passive and does not provide any active high output of its own. The High output is supplied by Vcc via the Rc or Rp pull-up resistors. The open collector or open drain will pull the pull-up resistor voltage down to the ground to create a low impendence, low logic state.
What component develops the output signal in a common emitter amplifier?
The voltage drop across the emitter-collector junction develops the output signal with the help of a resistor or two in series. The output is 'seen' at the collector.
What do you mean by common emmiter configuration?
In whch emitter is cmmön.input is taken frm base nd output is obtaind acros collector.
What is the input current for common collector?
from the name itself the common collector has its collector terminal in common with both the input and output circuits of a transistor and the base current is chosen as the input current and the output current is the emitter current
What is open drain or open collector?
Open drain or collector means ,collector and drain terminal of BJT and MOSFET will be left open during implementation/fabrication.They will not be connected from Supply Vcc or VDD.
What is the use of IC 7407?
7407 is "Hex Buffers/Drivers With Open-Collector High-Voltage Outputs". Buffers are used to clean up a noisy signal, to change from one voltage to another, or to convert a high output impedance to a low output impedance.
What is the phase relationship between the input and output signals of the common collector amplifier?
Common emitter is the only transistor configuration that has an 180 degree phase difference between input and output. Common base and common collector outputs are in phase with the input.***********************************That is incorrect.The output of the common emitter is inverted, there is no phase shift.
For common collector configuration op current is?
output current is emitter current i.e.,Ie
What digital multimeter scale should be used when testing the signal from a Hall-effect switch?
You should use the scale that shows correctly your supply voltage. Most Hall-effect switches provide either a logical output or an open-collector output. If the output is logical, you can expect the value to be between 0 and your supply voltage. If the output is open-collector, you must bias the output to your supply voltage with a resistor; otherwise you will always read "0". If biased, the output will be between 0 and the voltage bias. If you are not certain of which type you have, try finding the datasheet on the Internet; otherwise, you can always bias the output to your supply voltage; if you properly choose the resistor, it should not adversely affect the behaviour of the logical-level output. I would suggest trying 1 kOhm with a 5 V supply; this gives a bias current of 5 mA, which most Hall-effect sensors should be able to cope with. There are other Hall-effect sensors that provide linear output, but this answer is about a Hall-effect switch.
