Opto-isolators - Revision history

MattT at 20:51, 12 January 2009

2009-01-12T20:51:33Z

MattT at 20:21, 12 January 2009

2009-01-12T20:21:51Z

MattT at 20:21, 12 January 2009

2009-01-12T20:21:04Z

MattT at 20:17, 12 January 2009

2009-01-12T20:17:19Z

MattT at 04:06, 7 January 2009

2009-01-07T04:06:20Z

MattT at 04:05, 7 January 2009

2009-01-07T04:05:58Z

New page

Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation.

An opto-isolator is a small LED in close proximity to a phototransistor. The LED is driven by the transmitting circuit, while the phototransistor drives the receiving circuit. Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.

The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection. The bandwidth of signal transmission is dependent on the configuration used. For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.

Opto-isolators do not output square waves. For this reason, a comparator is needed on the output to ensure clean output signals. A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.

[[Image:Opto-isolator.jpg]]

[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here]Here is a great resource for further information and additional higher bandwidth circuit diagrams.

@@ Line 3: / Line 3: @@
 An opto-isolator is a small [[Using_LEDs_%26_IREDs|LED]] in close proximity to a [[Photodiodes_and_Phototransistors|phototransistor]].  The LED is driven by the transmitting circuit and an appropriate resistor is necessary, see the opto-isolator data sheet for assistance is sizing this. The phototransistor drives the receiving circuit.  Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.
-The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection.  The bandwidth of signal transmission is dependent on the configuration used.  For higher output to input current ratios, use an opto-isolator with a Darlington transistor pair in the output.
+The opto-isolators in the mechatronics lab (4N27) have a connection to base that can be used to change the properties of the connection.  The bandwidth of signal transmission is dependent on the configuration used.  For higher output to input current ratios, use an opto-isolator with a Darlington transistor pair in the output.
-Opto-isolators do not output square waves.  For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals.  A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.
+Opto-isolators do not output square waves.  For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals.  A possible configuration is shown below that uses the 4N27 and has a bandwidth of 20 KHz.
 [[Image:Opto-isolator.jpg]]

@@ Line 3: / Line 3: @@
 An opto-isolator is a small [[Using_LEDs_%26_IREDs|LED]] in close proximity to a [[Photodiodes_and_Phototransistors|phototransistor]].  The LED is driven by the transmitting circuit and an appropriate resistor is necessary, see the opto-isolator data sheet for assistance is sizing this. The phototransistor drives the receiving circuit.  Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.
-The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection.  The bandwidth of signal transmission is dependent on the configuration used.  For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.
+The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection.  The bandwidth of signal transmission is dependent on the configuration used.  For higher output to input current ratios, use an opto-isolator with a Darlington transistor pair in the output.
 Opto-isolators do not output square waves.  For this reason, a [[Comparators|comparator]] is needed on the output to ensure clean output signals.  A possible configuration is shown below that uses the 4N270545K and has a bandwidth of 20 KHz.

← Older revision		Revision as of 04:06, 7 January 2009
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	[[Image:Opto-isolator.jpg]]		[[Image:Opto-isolator.jpg]]

	[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here]~~Here~~ is a great resource for further information and additional higher bandwidth circuit diagrams.		[http://www1.jaycar.com.au/images_uploaded/optocoup.pdf Here] is a great resource for further information and additional higher bandwidth circuit diagrams.

@@ Line 1: / Line 1: @@
 Opto-isolators are used for the transmission of signals between components while maintaining electrical isolation.
-An opto-isolator is a small LED in close proximity to a phototransistor.  The LED is driven by the transmitting circuit, while the phototransistor drives the receiving circuit.  Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.
+An opto-isolator is a small [[Using_LEDs_%26_IREDs|LED]] in close proximity to a [[Photodiodes_and_Phototransistors|phototransistor]].  The LED is driven by the transmitting circuit and an appropriate resistor is necessary, see the opto-isolator data sheet for assistance is sizing this. The phototransistor drives the receiving circuit.  Opto-isolators are most effective for binary switching operations. Analog signals need a more complex transmission method such as pulse width modulation.
 The opto-isolators in the mechatronics lab (4N270545K) have a connection to base that can be used to change the properties of the connection.  The bandwidth of signal transmission is dependent on the configuration used.  For higher input to output current ratios, use an opto-isolator with a Darlington transistor pair in the output.