Photodiodes and Phototransistors - Revision history

Lynch: /* Phototransistors */

2011-02-09T01:43:06Z

Phototransistors

← Older revision		Revision as of 20:43, 8 February 2011
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	[[image:phototransistor.jpg\|left\|150px]]		[[image:phototransistor.jpg\|left\|150px]]
	[[image:phototransistor amplifiers.png\|right]]		[[image:phototransistor amplifiers.png\|right]]
	Phototransistors are transistors with the base terminal exposed. Instead of ~~applying~~ a ~~voltage to~~ the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.		Phototransistors are transistors with the base terminal exposed. Instead of sending current into the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.

	*'''Common-Emitter Amplifier''' - goes from "high" to "low" with light.		*'''Common-Emitter Amplifier''' - goes from "high" to "low" with light.

2008-12-13T03:29:53Z

Applications

← Older revision		Revision as of 22:29, 12 December 2008
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	<br clear=all>		<br clear=all>
	* [[~~Position~~-~~Sensitive~~ ~~Detection~~\|Position-sensitive detector]]		* [[Lateral-Effect Photodiode\|Position-sensitive detector]]

	==References==		==References==

2008-12-13T03:29:03Z

Applications

← Older revision		Revision as of 22:29, 12 December 2008
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	<br clear=all>		<br clear=all>
	* [[Position-Sensitive ~~Detector~~\|Position-sensitive detector]]		* [[Position-Sensitive Detection\|Position-sensitive detector]]

	==References==		==References==

2008-12-13T03:28:41Z

Applications

← Older revision		Revision as of 22:28, 12 December 2008
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	[[image:optocoupler.png\|center]]		[[image:optocoupler.png\|center]]

			<br clear=all>
			* [[Position-Sensitive Detector\|Position-sensitive detector]]

	==References==		==References==

2008-04-16T00:03:02Z

Comparison

← Older revision		Revision as of 19:03, 15 April 2008
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	* '''Frequency Response'''		* '''Frequency Response'''
	*: Photodiodes are much faster than phototransistors (nanoseconds vs. ~~milliseconds~~)		*: Photodiodes are much faster than phototransistors (nanoseconds vs. microseconds)

	* '''Gain'''		* '''Gain'''

2006-07-12T17:35:48Z

Comparison

← Older revision		Revision as of 12:35, 12 July 2006
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	* '''Frequency Response'''		* '''Frequency Response'''
	*: Photodiodes are much faster than phototransistors		*: Photodiodes are much faster than phototransistors (nanoseconds vs. milliseconds)

	* '''Gain'''		* '''Gain'''
	*: Phototransistors have a higher gain		*: Phototransistors have a higher gain. Photodiodes require an amplifier to use.

			* '''Temperature Response'''
			*: Photodiodes vary ''less'' with temperature

	==Applications==		==Applications==

2006-07-12T17:33:05Z

Phototransistors

← Older revision		Revision as of 12:33, 12 July 2006
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	==Phototransistors==		==Phototransistors==
	[[image:phototransistor.jpg\|left\|~~200px~~]]		[[image:phototransistor.jpg\|left\|150px]]
⚫	Phototransistors are transistors with the base terminal exposed. Instead of applying a voltage to the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.
	[[image:phototransistor amplifiers.png\|right]]		[[image:phototransistor amplifiers.png\|right]]
		⚫	Phototransistors are transistors with the base terminal exposed. Instead of applying a voltage to the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.

	*'''Common-Emitter Amplifier''' - goes from "high" to "low" with light.		*'''Common-Emitter Amplifier''' - goes from "high" to "low" with light.

2006-07-12T17:32:25Z

Phototransistors

← Older revision		Revision as of 12:32, 12 July 2006
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	==Phototransistors==		==Phototransistors==
	[[image:phototransistor.~~png~~\|left]]		[[image:phototransistor.jpg\|left\|200px]]
	Phototransistors are transistors with the base terminal exposed. Instead of applying a voltage to the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.		Phototransistors are transistors with the base terminal exposed. Instead of applying a voltage to the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.
	[[image:phototransistor amplifiers.png\|right]]		[[image:phototransistor amplifiers.png\|right]]

2006-07-12T17:31:52Z

Phototransistors

← Older revision		Revision as of 12:31, 12 July 2006
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	==Phototransistors==		==Phototransistors==
			[[image:phototransistor.png\|left]]
		⚫	Phototransistors are transistors with the base terminal exposed. Instead of applying a voltage to the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.
	[[image:phototransistor amplifiers.png\|right]]		[[image:phototransistor amplifiers.png\|right]]
⚫	Phototransistors are transistors with the base terminal exposed. Instead of applying a voltage to the base, the photons from striking light activate the transistor. Other than that, the phototransistor behaves just like a normal transistor. Two common configurations are shown on the right.

	*'''Common-Emitter Amplifier''' - goes from "high" to "low" with light.		*'''Common-Emitter Amplifier''' - goes from "high" to "low" with light.
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	*'''Active Mode''' - In active mode, the output of the transistor is proportional to the intensity of the light.		*'''Active Mode''' - In active mode, the output of the transistor is proportional to the intensity of the light.


	==Photodiodes==		==Photodiodes==

2006-07-06T22:30:36Z

← Older revision	Revision as of 17:30, 6 July 2006
(No difference)