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Sender: "piclist-bounces@mit.edu" Date: Wed, 12 Feb 2020 06:31:21 -0800 Subject: Re: [EE] TL431+NPN as rated series regulator? Circuit questions. Thread-Topic: [EE] TL431+NPN as rated series regulator? Circuit questions. Thread-Index: AdXhstF1auDdE37aQI69smU1kfDofw== Message-ID: References: List-Help: List-Subscribe: , List-Unsubscribe: , In-Reply-To: Reply-To: Microcontroller discussion list - Public. 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I presume they meant 2N2222 not 2N222 (an ancient germanium transistor) On Tue, Feb 11, 2020, 12:35 PM Jason White < whitewaterssoftwareinfo@gmail.com wrote: > Hello everyone, > > The TL431 datasheet shows the attached circuit has an example of how > to create a series regulator. > > I would like some help understanding the purpose of C1, RA, and RB. > > I assume RA is to prevent oscillation? > What is C1's purpose? Why is C1 from cathode to reference? (to prevent > oscillation?) > What is RB's purpose? (to improve turn off time?) > > -- > Jason White > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .