This part is a kind of semiconductor called THB6128.

Function of this product has Development Specification Proposal.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

THB6128 Development Specification Proposal 1. Application: PWM current control stepping motor driver 2. Package: MFP30KR 3. Features      1 channel PWM current control stepping motor driver BiCDMOS process IC Output on-resistance( High side 0.3 Ω, Low side 0.25 Ω, Total 0.55 Ω; Ta = 25°C, Io = 2.0 A) 2, 1-2, W1-2, 2W1-2, 4W1-2, 8W1-2, 16W1-2, 32W1-2 phase excitation are selectable Advance the excitation step with the only step signal input  Available forward reverse control  Iomax=2.2A     Over current protection circuit Thermal shutdown circuit Input pull down resistance With reset pin and enable pin 4. Absolute Maximum Ratings at Ta = 25°C Parameter Symbol Supply voltage VMmax Output current Iomax Logic input voltage VINmax VREF input voltage V [ ... ]

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