| ??? 04/21/10 15:20 Read: times |
#175228 - This is not rocket-science Responding to: ???'s previous message |
Sivanand Somasundaram said:
Yeah I have been already looking into these drivers but the problem with these drivers is once my TTL input goes high the output makes the valve ON and OFF at a frequency and duty cycle determined by values of capacitance and resistors connected to the different pins and when TTL goes low the valve remains in the normal default state(close/open)
You've got me confused now ... Isn't the "normal"/default state of the MCU pins a '1'? That's what happens when you turn on the power. Now ... to what frequency are you referring? How is it generated? Don't you have complete control of that? What resistance and capacitance do you mean? But my requirement is i want the valve to remain open continuously until the TTL goes to low.
If the driving signal from the MCU is a '1', doesn't the relay stay in whatever state that brings about until you change it? Only option with these drivers is to make duty cycle 100% .But I am not sure whether it is possible practically ..they have resistors listed up to 95 % duty cycle.
Perhaps you should show us what you mean. Normally, one would send current through the input circuit of a relay in order to turn it ON. It would stay that way until it's going to be turned OFF. If your relay is a latching type, then the specifications will tell you how long a pulse you have to send it. Again, YOU can precisely control that with firmware. I am also wondering how these drivers are classified because i see many types all looking similar.
Some are called low side driver and some are called high side driver??? A high-side driver sources current TO the input circuit (coil) of the relay. A low-side driver sinks current FROM the input circuit(coil) of the relay. The low-side driver is much more common, and is much simpler. As a result, more high-side drivers are offered at substantial cost. It's up to you which type you prefer. Driving a relay is really easy. All you have to do is search on 8052.COM and you'll find lots of information. I don't know why this is such a problem for you. Have you tried searching yet? RE |
| Topic | Author | Date |
| solenoid driver | 01/01/70 00:00 | |
| switch on and off at high speed | 01/01/70 00:00 | |
| speed range | 01/01/70 00:00 | |
| the typical circuit | 01/01/70 00:00 | |
| clarification | 01/01/70 00:00 | |
| "ASCII schematic" | 01/01/70 00:00 | |
| ASCII schematic is useful!!! | 01/01/70 00:00 | |
| answers | 01/01/70 00:00 | |
| It's in the FAQ | 01/01/70 00:00 | |
| Thanks for the reference | 01/01/70 00:00 | |
| Have you considered a "solenoid driver"? | 01/01/70 00:00 | |
| Ready made solenoid drivers | 01/01/70 00:00 | |
| recognized my error | 01/01/70 00:00 | |
| This is not rocket-science | 01/01/70 00:00 | |
| Check the data sheet you linked... | 01/01/70 00:00 | |
Yes, people do have to read the datasheet | 01/01/70 00:00 | |
| re: solenoid driver | 01/01/70 00:00 |