| ??? 02/01/06 07:39 Modified: 02/01/06 08:43 Read: times |
#108860 - Description of the "Dispensing Unit" Responding to: ???'s previous message |
Suresh R said:
Kindly use the link given below to see the description this new thread.
http://www.8052.com/forumchat/read.phtml?id=108597 Since that description is buried in a whole load of other irrelevant stuff, here it is again: Suresh R said:
I need some ideas to build a circuit that works as a despensing unit.
The operation of an existing unit is as follows: The time(0 to 10 sec variable) is being set using a potentiometer arrangement. then, when a button is pressed(push button) the solenoid connected to the despenser at the o/p will be 'ON' till the time set is elapsed. I need to design a circuit for doing this operation. can any one give me suggestions on selecting appropriate components that could be used to do this job. could it be done using a micro. The following points arise: What are you dispensing? Your scheme can only work if you are 100% sure that the dispensing mechanism is 100% repeatable and 100% linear. How will you confirm that it has actually dispensed anything? If this is a medical device, you certainly need more than just a 555! You could certainly do this with a microcontroller - it's a simple timing project. As Steve said, a small micro could be cheaper than an appropriate capacitor! A micro would certainly be more accurate than a 555. |
