ORIGINAL: JNorton
Richard,
The really nice thing is that we are not dealing with RF generated noise. If U-dUd keeps to a linear model he will not have to either. Sanyo provides lots of charge and discharge graphs for each of their cells. Have you played with the PIC processors? I'm not saying that circuit layout is not critical at times but it is a lot less than I expected after dealing with dedicated embedded PC's of the early 90's. Lot's of manufactured experimental boards are out there with an area for analog breadboarding with the PIC area already fully debugged and assembled.
One other point power supply design can be a real ***** because you don't know if the load is reactive or inductive in nature. Designing a NiCd or a NiMh charger is simply a lot easier because you know exactly what the load is and your can use a proven power supply to power it. The other simplifying factor is the environment these chargers operate in is not an industrial one with lots of dirty AC but one in a residential setting.
John
No John never actually designed using a PIC all have been 68HC11, 8051 and INTEL 16 bit machines. I still teach and our program is 68HC11 in our micro term. The 48V SCR 200amp had a full microprocessor 8085 with 10bit A/D PWM modulation on a star with a inter phase tee. I know when someone talks about phase stability they have been their. But CPU control has two pole due the PS is typically separate. Today’s microcontroller have PWM timers so can to do it all, can get to a single pole shift. The real problem is the predictability of charge if I were to design a termination circuit (instead of plane building
) I’d ingrain a curve projection by using the battery input table therefore knowing capacity an charge rate pin point a spot on the curve an predict the delta rate change before the actual peak voltage. Problem is I used to get paid to think and had a R&D dept build it for me HEE HEE
Rich