2018-09-17
With the gate driver IC and the MOSFET in possession, it was time to experiment. Below is a potato-cam(tm) pic of the layout. Fun fact: initially I forgot to hookup the ground on the gate driver chip and spend 30 minutes scratching my head. It’s hard being dumb sometimes. So what we’re seeing on the right hand side is the 8 pin gate driver and below it to the right is the MOSFET. I am Read more…
2018-09-13
I have been playing with the PIC24 which will be the basis for the serial and power board. Side track: need a catchier name for the serial and power board. SPB? S and PB? SaPB? VSPB? Vic’s SPB? Executive decision made: VSPB – Vic’s Serial and Power Board. Boom. Done. I have been playing with the PIC24 which will be the basis for the VSPB. I don’t know if I like Microchip PICs because they’re Read more…
2018-09-08
Onto the Beaglebone shield. The goal of this project is to produce an expansion board for the Beaglebone that breaks out the RS232 ports, provides power for the Beaglebone, and controls the power to the IO boards. There are several reasons for wanting to control the power to the IO boards: The Beaglebone can not have any voltage applied to its inputs until a specific stage of the boot process. While we could achieve above Read more…
2018-09-07
So I have been playing with the board and I can not find any show-stopper problems. I have tested every feature and there is not a single problem that can’t be software calibrated or hand-waved away. No in no way am I implying that it is perfect. Far from it. But it’s good enough to do what I designed it to do. Could some things have been done differently? Better? More efficient? Sure, of course. Read more…
2018-09-03
I know I’ve said it before, but I will go ahead and say it again: the end is in sight. In the last few days I’ve addressed the last few remaining issues: 1. Persistent offset on analog input #8 (ICD4) Turned out to be an input voltage offset issue. See here for more details. 2. ADC input weirdness on analog inputs 4-8 (ICD inputs) The short version is that the op amp output is at Read more…
2018-09-01
One of the current and hopefully last hardware niggles is the unexpected value on the last analog input. It’s consistently reading millivolts higher than the other analog inputs. This has been verified with and without a device attached to it. The analog input in question is ICD4. Because I took a thing naming class at a community college, you can be absolutely clear that this is the fourth ICD input. When nothing is connected to Read more…