Open higaski opened 9 months ago
We have not tried the 1uH/2R filter... we instead switch briefly to high frequency PWM mode in software to handle in-rush, then switch back to DCC mode. This appears to work. Have you tried the 1uH/2R solution?
No, I'm no longer using this device.
we instead switch briefly to high frequency PWM mode in software to handle in-rush, then switch back to DCC mode. This appears to work.
Does this mean the output is not DCC during startup?
we instead switch briefly to high frequency PWM mode in software to handle in-rush, then switch back to DCC mode. This appears to work.
Does this mean the output is not DCC during startup?
It is DCC on startup, and only switches to PWM if a short is detected at the point that particular output channel is turned on by software, and then only very briefly, sufficient to charge capacitors causing the in-rush issue in the first place.
Hello
Out of curiosity, have you ever fixed the issue described in the e2e forum here: https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1249338/drv8874-unrush-current-trippling-fault-due-to-capacitance-of-circuit
There is an accepted answer (green border around a post?) which mentions to put the IMODE pin into STATE Quad-Level 2 (basically adding 20k to GND), but from how I understand the datasheet that wouldn't really fix things and an overcurrent fault would still occur.
I'm thinking about putting a 1uH // 2R filter on the output stage to solve this.