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Title: Stepper motor controller/driver with ST L6470 Post by: davorin on January 14, 2011, 05:44:41 17:44 Has someone already used the L6470 in a new design or experimented with the EVAL6470 kit from ST?
Do those little HTSSOP packages really don't need any heatsinks for stepper motor currents up to 3A RMS? But looks like those devices aren't available much at this time....at least I could order the EVAL6470 from mouser.com and should arrive next week...hopefully with my 3A 3Nm stepper motors as well (o; Title: Re: Stepper motor controller/driver with ST L6470 Post by: TomJackson69 on January 15, 2011, 12:17:42 00:17 I have not use this IC. But look at the spec, the Rds(on) is very high compare to other devices I had been used.
For the part, I found: Digikey already has IC and KIT: For KIT: cost $63.00 For IC: cost $12.32 Tom Title: Re: Stepper motor controller/driver with ST L6470 Post by: tedz on February 19, 2011, 10:21:14 22:21 Note a few things on the data sheet:
First, the package has an "EPAD" on underside for cooling purposes. The cooling is through the circuit board. That's how you can dissipate significant power in such small and "flimsy looking" package. Secondly, the chip has also thermal protection and other protections. I have not personally used this chip, but I wouldn't be too worried: I have used an power op-amp in the same type of package, and even placed a cooling fin on the opposite side of the circuit board. No trouble at all, actually I over-designed it, and the chip was cool as a cucumber. Could have skipped the cooling fin and thermally conductive epoxy glue.... Often, if not loading too heavily the printed circuit board may be good enough heat sink alone for these packages. You should calculate the expected max. dissipation and then calculate the temperature rise for it - with circuit board copper cooling it, or with an extra cooling, if absolutely required. Look also at ST's web site for their evaluation board. There you can see the cooling "contact" area as well, using the circuit board only: http://www.st.com/internet/analog/product/248592.jsp good luck, tedz Title: Re: Stepper motor controller/driver with ST L6470 Post by: The_Mole_763682 on March 24, 2011, 12:22:09 00:22 I looked for the 6470, but didnt have much success with available parts or sensible prices, but I did find a TB6560 board already made on eBay for quite a good price
I paid 33 GBP including delivery for a 3 axis stepper controller. - this is LESS than the cost of buying the parts! search for this in ebay CNC TB6560 3 Axis Stepper Motor Driver Controller Board it is shipping from Hong Kong. I am also awaiting delivery of a PCB CNC router from Taiwan - so I can protoype PCB's at home --- Excited!!! -Mole Title: Re: Stepper motor controller/driver with ST L6470 Post by: solutions on March 24, 2011, 05:55:11 05:55 I looked for the 6470, but didnt have much success with available parts or sensible prices, but I did find a TB6560 board already made on eBay for quite a good price Some tech info on that board here: http://reprap.org/wiki/4_Axis_TB6560_CNC_Stepper_Motor_Driver_Board_ControllerI paid 33 GBP including delivery for a 3 axis stepper controller. - this is LESS than the cost of buying the parts! search for this in ebay CNC TB6560 3 Axis Stepper Motor Driver Controller Board it is shipping from Hong Kong. I am also awaiting delivery of a PCB CNC router from Taiwan - so I can protoype PCB's at home --- Excited!!! -Mole A lot of people having problems with it, it seems. Sounds like the designers didn't stuff enough smoke into the board. Title: Re: Stepper motor controller/driver with ST L6470 Post by: The_Mole_763682 on March 27, 2011, 01:06:57 01:06 Some tech info on that board here: http://reprap.org/wiki/4_Axis_TB6560_CNC_Stepper_Motor_Driver_Board_Controller A lot of people having problems with it, it seems. Sounds like the designers didn't stuff enough smoke into the board. Interesting.. I wish I had know that before I paid :D however, all is not lost as the motors I have to hand don't need a lot of smoke to run.. 4.25v, 0.425A / phase, so hopefully all the magic smoke will stay in place for my baby project. |