[carl benz]

new in forum & i need help ,recently i've build 3 linisteppers v2 ,for the moment i want to drive a 7 amps stp motor ,any ideas ?
i'm thinking in adding 4 db911 driven by the tip122, i'm not sure but it seems gonna work,

[James Newton]

Linear drivers are not practical for driving those sorts of loads.

Mariss Freimanis of geckdrive.com says: "A switching type drive makes sense when the power levels are large. The inefficiency of a linear drive becomes prohibitive at such levels. At 7A and 80V, a classic linear drive dissipates an unacceptable 560 Watts of heat in the power transistors.

At the other extreme, say 1A and 24V, the complexity of a switching type drive makes less sense. Heat dissipation then is a manageable 24 Watts and the simplicity and other advantages of a linear amplifier becomes appealing."

7 amps is well past the 1 to 3 amp advertised ability of the Linistepper.

Buy a gecko or look at the mardus-kreutz chopper driver.

[Yachaan]

Try Mardus Kreutz:
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