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MAX22201 stuck in Fault mode

Category: Hardware
Product Number: MAX22201ATC+

I created a PCB design using the MAX22201ATC+, applying +24V to VM (Pin 10), and tying pins 3 and 8 to the ground pad of the chip, which is itself connected to a larger ground plane.  I added a resistor position for ROFF (pin 2), but I left that position as DNI so as to use the default 20us t-OFF as stated in the datasheet.  Similarly, I created a resistor position for the ILIM pin (pin 1) and left that as DNI, electing to use the internal current monitoring and limiting, again as stated in the datasheet.

I added some fast recovery diodes to the output pins as back-EMF protection.  I have tied a 1uF bypass capacitor to pin 10, as well as a 47uF tantalum capacitor as bulk capacitance, with additional 1uF bypass cap on V18 (pin 7).

I have configured the FAULT (pin 12) with a red LED such that when it goes active low, I will see a visual indicator.

I have confirmed that the device is entering sleep mode when I put power to the board, because the microcontroller I'm using is still processing the start-up code that I have in place, and per the MAX22201 datasheet, if the device is powered and both inputs are low, the chip goes to sleep.  Once the MCU initialization code is complete, the MCU then sets both of the driver input pins high for 5ms to wake the driver before attempting to control the motor down-stream.  When I then turn one or the other input pin off, the driver immediately enters fault mode, and I am unable to get the chip to do anything other than FAULT, although this fault does go away when I reassert logic high to both inputs.  This is braking mode, as stated in the datasheet.

I've gone through my prototypes thoroughly and have confirmed that I have no shorts between the 5V and 24V, or between either power supply and ground.  I've confirmed that the outputs are not shorted to each other and only connect to the output pins of the connector I've put on the board.  My input pins are also not shorted, and I've confirmed that I'm getting signal to the inputs of the driver.  My grounds all have continuity with ground and nothing else.

I've even gone so far as to compare my layout to the design of the MAX22201 Eval board, hoping to glean some insight as to what I may have done wrong.  Unfortunately, my layout is very similar to the Eval board, and only differs in that I incorporated bulk capacitance as the datasheet suggested and the ILIM and ROFF pins are configured a little differently.  I see nothing from a design standpoint that differs significantly from what I've created.

Anyone have any thoughts as to why I'm going into FAULT and unable to clear it?

[edited by: GenevaCooper at 3:15 PM (GMT -5) on 22 Nov 2023]