Other Parts Discussed in Thread: DRV2604, DRV2605, DRV8601, USB2ANY
SUBJECT : DRV2603 not working properly with tested LRA HAPTIC DEVICES
The Tests have been performed with the DRV2603 EVALUATION KIT.
To compare outputs with and without AUTORESONANCE, the figures have been taken using the BINARY COUNTING MODE, MODE 9. This mode simulates an OPEN LOOP (as we have readed, making the output as it was an ERM and creating a square wave via PWM at a selectable frecuency). In this mode we can compare the OUTPUT WITH and WITHOUT AITORESONANCE.
Page 14/ EVAL BOARD DATA SHEET SLOU340B
All the tested devices are glued to a MASS like in the EVALUATION BOARD.
The tested LRA´s are :
The LRA that is on the EV KIT (reference not Known).
The LV101040A from KOTL (2.7G)
The G1040003D from KOTL (2G)
The results are (ONLY POSITIVE PART OF THE WAVEFORM SHOWN)
WITH THE LRA THAT THE EVALUATION KIT HAS PLACED, ALL SEEMS TO WORK OK
WITH THE LRA 2G REFERENCE G1040003D, DRV2603 IS NOT WORKING
LRA SPECS :
https://www.vibration-motor.com/coin-vibration-motors/coin-linear-resonant-actuators-lra/g1040003d
WITH THE LRA 2.7G REFERENCE LV101040A, DRV2603 IS NOT WORKING
LRA SPECS :
https://www.vibration-motor.com/linear-resonant-actuator-lra-vibration-motors/lv101040a
CONCLUSIONS
The LRA AUTORESONANCE is only working with PART that the EV KIT mounts from origin. The other tested PARTS are not resonating OK.
When tested in OPEN LOOP, as expected, the waveforms are OK, but when tested in CLOSED LOOP the waveforms don´t follow the expected behaviour, and the haptic effect is distorted and very poor.
We need very simple vibration patterns, so we do not need more complicated IC´s (such as DRV2604/5), but we have also tested this parts with the EVAL BOARD DRV2605 with also poor results.
At this time we are thinking on driving the LRA via the DRV2603 simulating OPEN LOOP, or using the DRV8601 (not tested…).
One point we suspect (it´s only my opinion) is that it seems that these LRA´s have a more soft resonating CURVE (see it on its data sheets), and this can make the DRV2603 not finding a correct resonance.
Any help Will be appreciated, because we need to decide the LRA and Driver for a new product.
