DRV2625: Production Fixture for Auto-Calibration

Antonio Fadhel

Part Number: DRV2625

Hi Team,

Are there any mechanical requirements to achieve optimal DRV2625 auto-calibration results? If so, do we have any recommendations on placement or securing of the device while performing production auto-calibration?

Thanks,

Antonio

over 2 years ago

0 Carson Allen over 2 years ago

TI__Genius 13610 points

Hey Antonio,

There are no specific mechanical requirements except for the fact that it works best when the actuator in question is firmly glued to a mass for it to be able to propagate its vibration without moving.

Take this picture as an example of the DRV2625EVM where the actuator is located on a mass of metal with insulation between it and the ground so that optimal auto-calibration can be achieved for that LRA. But the test mass should be chosen based on what the LRA or ERM will be vibrating in the end product

Best,

Carson

Low Power Audio Applications

0 Antonio Fadhel over 2 years ago in reply to Carson Allen

TI__Genius 9410 points

Hi Carson,

The application is a wearable device and auto-calibration will be performed in production after board assembly. Do you have a similar suggestion for fixture at the board level where the actuator is already installed?

Thanks,

Antonio

0 Carson Allen over 2 years ago in reply to Antonio Fadhel

TI__Genius 13610 points

Hey Antonio,

Auto-Calibration can be performed anytime, so as long as you program it correctly auto-calibration will run anytime the device is powered on. And the auto-calibration will work best once the actuator is attached to final product or board so that it can be optimized for that specific mass, but auto-calibration is not necessarily a one time thing, it can be set occur when ever the device is power on and off but is not a requirement so long the processor controlling the device saves the register values associated with autocalibration and just writes them back to the DRV when device powers on. But for optimal calibration the actuator being calibrated should be attached to the final product or similar mass.

This FAQ may help you:

https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/917352/faq-drv2624-principals-and-method-of-auto-calibration-for-drv2624-drv2625?tisearch=e2e-sitesearch&keymatch=drv2625#

Or the quick start guide here also goes over it starting on p.9:

https://www.ti.com/lit/an/slaa950/slaa950.pdf?ts=1625063222596&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FDRV2625

Best,

Carson

Motor drivers

Motor drivers forum

DRV2625: Production Fixture for Auto-Calibration