All Forums  Electronics  Other Circuits  555 PWM

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize: 640 x 480 800 x 600 1024 x 768 1280 x 1024 UserName: Password: Format Mode: Basic  Help  Prompt  Format: Font Andale Mono Arial Arial Black Book Antiqua Century Gothic Comic Sans MS Courier New Georgia Impact Lucida Console Script MT Bold Stencil Tahoma Times New Roman Trebuchet MS Verdana   Size 1 2 3 4 5 6   Color Black Red Yellow Pink Green Orange Purple Blue Beige Brown Teal Navy Maroon LimeGreen Message: * HTML is OFF * Forum Code is ON Smilies [quote][i]Originally posted by sergiosparks[/i] [br]I made an astable circuit using 555 timer to output pulses for the LTC1155 MOSFET driver to variably drive a 100 w 12 v blower .The MOSFET is 50N06 and the data sheet says that its On resistance is about .023 Ohm ,50 A,60 V.I paralled 2 of them to even get lower resistance I can measure about 11 amps of current going to the motor at full speed...how come its still generating a lot of heat even at lower speed even though I installed heatsink about 1" by 2" on each Mosfet? I'm imagining that each pulse is still 12v in amplitude though..the heat is like a fresh hot coffee..I don't have a measuring device for it..with out the heat sink the solder from the power supply would melt away..that must be a lot of degrees F or C..right now its working tested for about 15 min. but I'm still worried about the heat..my power supply aggress with the mosfets.. [/quote]    Insert an Image File (GIF, JPG, JPEG, BMP, ZIP, PNG) Check here to include your profile signature.