Los Frijoles
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I am using a HIP4081A to control a full mosfet h-bridge for a 40-amp motor driver. The system runs off 7.2V and the HIP4081A is running off a boost converter to get the necessary 12.
The problem I have been having is that whenever the motor turns on/starts moving, the supply voltage dips, immediately dropping the boost output below 9V (my controller cannot react fast and accurate enough), the cutoff limit for the bridge. After a few cycles of this, the breadboard begins to smoke and the chip gets fried along with (sometimes) a mosfet
The control system is as such for the HIP4081A: the high mosfet lines are tied together and are pwm'd to give the motor it's speed. The low mosfet lines are on a logic inverter so they are always opposite and at least one is always on. This controls direction.
It appears that when the supply voltage dips, all the mosfet gates are brought low, shutting them off. I previously had a problem with inductance and stored energy cycling around searching for a path to ground and eventually breaking through the chip "sense" inputs, frying the chip. Would all paths to ground shutting off (the low side mosfets being brought low) with the motor still spinning cause this problem?
Have I designed this driver badly or do I need to correct my control method? I can give schematics or whatever is needed to answer this question.
The problem I have been having is that whenever the motor turns on/starts moving, the supply voltage dips, immediately dropping the boost output below 9V (my controller cannot react fast and accurate enough), the cutoff limit for the bridge. After a few cycles of this, the breadboard begins to smoke and the chip gets fried along with (sometimes) a mosfet
The control system is as such for the HIP4081A: the high mosfet lines are tied together and are pwm'd to give the motor it's speed. The low mosfet lines are on a logic inverter so they are always opposite and at least one is always on. This controls direction.
It appears that when the supply voltage dips, all the mosfet gates are brought low, shutting them off. I previously had a problem with inductance and stored energy cycling around searching for a path to ground and eventually breaking through the chip "sense" inputs, frying the chip. Would all paths to ground shutting off (the low side mosfets being brought low) with the motor still spinning cause this problem?
Have I designed this driver badly or do I need to correct my control method? I can give schematics or whatever is needed to answer this question.
