I apologize for asking something dumb=85. How many hardware prototypes do you have ? I hope at least two and it would be better if you have 4 or more. The hardware could be bad and if you have but one instance =85 you will not be able to debug. I will be happy to assist them in any case. Do you have any photos ( closeups ) of the hardware ? Gus in Denver yes@nope9.com skype WFTelectronics On 2015m02d20, at 14:19, Gary Neal wrote: Group, I've recently inherited a college student team competing in the Shell Eco-m= arathon competition which is held April 9th (short fuse) in Detroit. As pa= rt of this competition, students are required to custom design their own Mo= tor Controller to, in our case, control a 36V, ~600W BLDC wheel hub motor. = Previous semesters of students built a circuit card assembly, around Alleg= ro's A3938 chip (http://www.allegromicro.com/en/Products/Motor-Driver-And-I= nterface-ICs/Brushless-DC-Motor-Drivers/A3938.aspx), that unfortunately doe= sn't work. This semester's students have been trying to make the previous = design function, and they're making progress but have so far been unsuccess= ful. As I'm a mechanical engineer (with some EE experience), I haven't bee= n all that much help. Has anyone else used this A3938 MC IC before and have any suggestions on ho= w to proceed? Right now, their latest symptom involves the A3938's truth table (hall sens= or input vs. gate drive/phase output). The table shows with any given hall= sensor input combination, only one high side and one low side gate drive s= hould be on. Upon reading the outputs of the gate drives, the students saw= exclusively two high side and two low side gate drives on with any given h= all sensor input combination (they checked about 10 combinations), and all = of the gate drives read odd voltages (between 6V and 25V). Any help is greatly appreciated! Gary --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .