LiquidKernel
New Member
Hi everyone, I am working on a project where I am going to duplicate the auto-power window feature of the Volvo S60 into my Volvo 850. My car uses a relay to drive the "auto" feature for down on the driver's side window only. The S60 however, does both up and down for all four windows without the use of relays.
I also wanted to avoid using relays as I'd need two per window (based on the schematic in the link below), but as long as I can use a cheap 12V coil voltage relay from Mouser that I can acquire for $0.80/each, I will have no problem with it.
My car uses an interesting way to move the windows up and down. Instead of inverting the ground and +12V line to the motor, it keeps the ground connected to both leads of the motor. Then depending on which way you need to move the window, removes the ground from the required lead and instead puts +12Vs to it.
What I would want to do is have an MCU (Atmel most likely) to detect a 1/2 second pulse (no more, no less) to trigger a SPDT relay that would send +12Vs to the needed lead.
However, how would I drive the coil of let's say a 12V coil voltage relay with an MCU? Optocouplers?
Or, how would I be able to (cheaply) duplicate an SPDT relay using solid-state devices such as power MOSFETs?
Here is the schematic (you have to copy-paste the link):
**broken link removed**
Thank you for any help.
I also wanted to avoid using relays as I'd need two per window (based on the schematic in the link below), but as long as I can use a cheap 12V coil voltage relay from Mouser that I can acquire for $0.80/each, I will have no problem with it.
My car uses an interesting way to move the windows up and down. Instead of inverting the ground and +12V line to the motor, it keeps the ground connected to both leads of the motor. Then depending on which way you need to move the window, removes the ground from the required lead and instead puts +12Vs to it.
What I would want to do is have an MCU (Atmel most likely) to detect a 1/2 second pulse (no more, no less) to trigger a SPDT relay that would send +12Vs to the needed lead.
However, how would I drive the coil of let's say a 12V coil voltage relay with an MCU? Optocouplers?
Or, how would I be able to (cheaply) duplicate an SPDT relay using solid-state devices such as power MOSFETs?
Here is the schematic (you have to copy-paste the link):
**broken link removed**
Thank you for any help.