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New products: MP6500 Stepper Motor Driver Carriers
We are excited to expand our colorful selection of stepper motor drivers with carrier boards for the brand new MPS MP6500 stepper motor driver!
Monolithic Power Systems’ MP6500 can drive a bipolar stepper motor from a 4.5 V to 35 V supply with up to 1/8-step microstepping. On our four-layer, 2 oz copper carrier boards, the MP6500 can deliver up to approximately 1.8 A per phase continuously without a heat sink or forced air flow, making this new module the highest-current stepper motor driver we carry among all the ones that share this form factor.
14 March 2018 Update: After further testing of more units, our initial characterization of the maximum continuous current capability was too high, so we have lowered it to 1.5 A. Please keep in mind that the exact maximum current you can get out of the driver at a given temperature will depend on your supply voltage and stepper motor characteristics.
Unlike most other stepper motor drivers, the MP6500 features internal current sensing, which allows it to measure the motor’s coil current even during the off period of the PWM cycle. Combined with its automatic decay selection, this allows it to regulate the current especially accurately to produce smoother motion and higher speeds, as shown in the below oscilloscope capture from the MPS application note AN120 (1MB pdf).
Compare this with waveforms from a stepper driver that uses a more typical method of peak current control:
In addition to a version with potentiometer current control like most of our other stepper motor drivers, we also offer the MP6500 on a board with digital current control. This second version enables a microcontroller to dynamically set the current limit in steps of 0.5 A (up to a maximum of 2 A) by simply driving one or two inputs low. Alternatively, supplying an analog voltage or PWM signal allows finer control of the limit within the 0 to 2 A range.
Introductory special: just $2.97 each! Must use coupon code MP6500INTRO, limited to first 200 customers, limit 5 per customer.