This week's EYE ON NPI is a Texas-two-steppin' motion controller that takes your 2-axis motion control to the next level: it's ADI/Maxim/Trinamic's TMC5272 Dual-Axis Stepper Motor Controller and Driver IC.

We've been checking out many of Trinamic's great stepper motor driver chips lately and this one is the latest generation, with 2 drivers, plus motion control, for advanced usage even on boards that don't need real-time GPIO toggling for steps. Trinamic is definitely not a group that 'rests on their laurels': every year they are coming out with even more improvements to their awesome stepper motor drivers. This chip has 250 pages of datasheet and each page details yet another improvement or setting that will make your mechatronics fast, silent, and efficient.

What sets the TMC5272 (https://www.digikey.com/short/0mq250r7) apart? Well, the first big thing is you get double the fun with two full stepper drivers for X and Y axis support. The voltage range is 2-20V, so good for low to medium voltage motors. The tradeoff is you can only get 1.5A max peak current, 1.1A sine wave, but for most users that don't have massive steppers that is perfectly fine. There's also a lot more 'smarts' in this stepper than the ones even from a couple years ago: 8-point motion control, no-loss/no-sense-resistor current management, 2D trajectory management over two axes, encoder or reference switch inputs, sensorless standstill motion detection. Of course all the fixin's you expect from the previous generations are there: silent stepping, UART and SPI and step/dir interface, stallguard, 1 to 256 microstepping, and diagnostic output

But, it's in a 3x3mm WLCSP package: this means you'll need at least a 4 layer board and plugged vias. It also means heat dissipation might be more challenging than the drivers with the big ground pads. However, a nice tradeoff is that there is internal 'lossless' current sensing, so no chunky resistors are required. The upside of a WLCSP is that we have lots more pins for tons of interfaces.

Each driver can run one bipolar stepper motor, and has multiple interfaces for control. As usual there's the STEP/DIR interface. This is great for usage with older designs that expect to toggle GPIO on each step. However, the S/D pins are shared with some of the cool sensors/encoders/switches. Plus all the really cool things the chip can do are too complex to adjust with just a few GPIO, so to really get the most use you'll need to use one of the packetized interfaces: UART or SPI. UART is great if you happen to only have USB for your computer: you can always just use a USB-serial converter, and the controller can be daisy-chained for multiple drivers per UART. If you have extra GPIO and/or a dedicated SPI port, we would recommend that since it's much faster and you can easily add more chips with one chip-select per.

Some of the cool things you can do via the interface include a 8-point ramp controller: instead of stepping each motor and dynamically adjusting the micro-steps for speed/precision, the TMC5272 can do it all on its own. It can also handle knowing 'where' it is on an axis bar, by using the built in homing support. Homing can be done either by using the sensorless 'StallGuard' (https://www.analog.com/en/lp/001/building-better-stepper-motor-system.html) or with reference switches. You can wire the switches directly to the TMC5272 - good if you want to have slow motion homing since you don't have to whack into the end of the axis - and then let the chip manage where it is. Then you can tell it you want to move and when you want to get there, and the TMC will take care of the rest. For ultra-accurate motion control, you can connect an external optical or magnetic encoder to the motor shaft that will tell you exactly when a step has occurred. There's also a neat back-EMF sensor that can tell when the motor has moved while 'disabled' - good to know when you will need to do another homing step after re-enabling the motor.

There's also an TMC5272-EVAL-KIT eval board that you can plug-n-play for instant stepper motor usage (https://www.digikey.com/en/products/detail/analog-devices-inc-maxim-integrated/TMC5272-EVAL-KIT/22107596), it works instantly with the TMCL IDE for trying out the various programmable settings (https://www.analog.com/en/resources/evaluation-hardware-and-software/motor-motion-control-software/tmcl-ide.html) and turn the motor via the TMCL IDE which sends UART/SPI commands over their USB driver board, so it's perfect for verifying the performance with your desired motors.

If you want double the pleasure, double the fun of double-motor driving, you can pick up the ADI/Maxim/Trinamic's TMC5272 Dual-Axis Stepper Motor Controller and Driver IC (https://www.digikey.com/short/0mq250r7) from DigiKey today - it's in stock amp; ready to ship immediately! Place your order now amp; by tomorrow morning you can be step-step-stepping to the most advanced 2-axis motor controller design you've ever seen.