Electronic Projects, forums and more.

Go Back   Electronic Circuits Projects Diagrams Free > Electronics Forums > Electronic Projects Design/Ideas/Reviews


Electronic Projects Design/Ideas/Reviews Are you building an electronic project or want to? Maybe you need some assistance? Come and submit your electronic questions here and let our experienced members find a solution.

Reply
 
Thread Tools Display Modes
Old 5th November 2003, 10:00 PM   (permalink)
Default Delay ckt

I am designing a fan control circuit using a microchip TC670. This ciruict will reside in a 1U chassis for 8 fans. I have (1) ALM LED on the front panel. If a fan dies, the LED will light. The problem with the 670 is, it faults immediately until RESET. Since it takes a while to power up the motherboard, the chip senses fan failure immediately then faults. I need to delay the funciton of the chip for at few seconds to allow the computer to competely power up.
tewills is offline   Reply With Quote
Old 6th November 2003, 05:21 AM   (permalink)
Default

Apply a capacitor to threshold pin. 0.5....10uF
Sebi is offline   Reply With Quote
Old 6th November 2003, 05:22 PM   (permalink)
Default Delay ckt

Thanks Sebi, since there are (8) fans, I need to use (8) TC670.s Which means everything will be multiplied by the quantity of (8). Would that include the cap you recommended? Or should your cap suggestion be in parallel with the Threshold (or ground).
Attached Images
File Type: gif fanckt.gif (4.9 KB, 153 views)
tewills is offline   Reply With Quote
Old 6th November 2003, 07:54 PM   (permalink)
Default

Yes, between the threshold input and GND.
Attached Images
File Type: gif fanckt_901.gif (5.7 KB, 159 views)
Sebi is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes




All times are GMT. The time now is 06:25 PM.


Electronic Circuits  |  Electronics Wiki
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.