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I recently bought this MX1508 module from AliExpress.

PCB photo - edited version from seller's webpage

I'm very impressed by its working given the low product cost. I would like to implement this in my next design, but I'm unable to find any schematics of the module online, neither is there any data sheet with an application circuit. Can anyone please share the schematic diagram of this module?

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    \$\begingroup\$ It looks like a simple board, you should be able to deduce the schematic from the PC board. If you can't follow the traces by eye, just use an ohm meter the measure continuity. You can find tons of schematics for similar circuits by just googling L298N schematic. \$\endgroup\$
    – crj11
    Dec 11 '18 at 13:34
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    \$\begingroup\$ Not sure what that chip is, but it isn't an L298N st.com/content/ccc/resource/technical/document/datasheet/82/cc/… \$\endgroup\$
    – Phil G
    Dec 11 '18 at 15:26
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    \$\begingroup\$ @Phil G - the chip is the MX1508... I think \$\endgroup\$
    – mike65535
    Dec 11 '18 at 15:34
  • \$\begingroup\$ sales.dzsc.com/486222.html just in chinese but maybe it helps \$\endgroup\$
    – Tellerrand
    Apr 16 '19 at 12:25
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I also did not find any schematics, so here the results from reverse engineering:

  • 4 Channels like many H-Bridges
  • +/- is the high voltage source/input
  • IN1-4 are the input signals from your IC (pwm capable)
  • Motor A/B are the high voltage outputs (connect motor here)

Experiments:

  • drives brushed motor in both directions (tested)
  • drives brushed motor at different speeds with pwm (tested)
  • does not drive BLDC properly using three phase pwm (choppy movement, jumping)
  • direct replacement with an L298 makes smooth BLDC movement (code/wiring tested ok)

The pwm test is run on positive voltages only 0,0.5,1 instead of -1,0,1 as that's the usual setup.

Guess:

  1. the MX1508 is to slow at reversing
  2. the MX1508 cannot "sink" at "0.5"

Resumee:

  • usable for space saving brushed setups
  • not usable for BLDC
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  • \$\begingroup\$ Good report. Thanks! How about steppers? Do you think it can be any good for low power bipolar motor? \$\endgroup\$
    – hypers
    Nov 24 '20 at 21:17
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If anyone wants to know about diagram then here it is. I draw it . And I like to share it with you guys.

enter image description here

Mx1508 diagram.

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    \$\begingroup\$ Welcome to EE.SE. We call that the PCB layout. A schematic might be more useful. You can add one in using the CircuitLab button on the editor toolbar. Double-click a component to edit its properties. 'R' = rotate, 'H' = horizontal flip. 'V' = vertical flip. Note that when you use the CircuitLab button on the editor toolbar an editable schematic is saved in your post. That makes it easy for us to copy and edit in our answers. You don't need a CircuitLab account, no screengrabs, no image uploads, no background grid. \$\endgroup\$
    – Transistor
    Jul 6 '19 at 9:08

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