Hello Paul:
Let me start by saying I am excited about the product, I've been a Freescale person since they were Motorola and used the early 6800 series, and watched them do what I think was the first ADC on the same die as the microcontroller. Very cool stuff at the time. Also, we were coding in assembly and sometimes BASIC, and FORTH...that is until C came along; thank heaven for that!
So now you build a nice micro soldered and tested on a super small USB board with a lightning fast core and peripherals and a 13-14 (effective) bit ADC....all for under 20 bucks! So far I have 3 of them, with plans on 10 more for my prototypes, and then about 1K per year, which in the PV solar business is pretty low volume. Why not spin my own controller? Easy: For that volume it is just not worth it. 10k/yr...that is another whole potato, for that I'd design my own controller, like we did at Trace, Xantrex, Outback, and Magnum before.
I've got a good part of my application going, but I still need use a good, fast, (and did I mention) cheap comparator. Comparators are often used for motor control/inverter/charger MOSFET power sections, where you need fast overcurrent detection to keep the power devices from letting the smoke out, or for very quick and consistent AC zero crossing detection to get accurate AC RMS samples and for grid synchronization. If your inverter does not sync perfectly with the grid, this is not a good thing!!
The Teensy 3.0 has two on-die comparators - CMP0 and CMP1. Would it be possible to have a few functions that use one or both of these? It would be helpful to have the DAC reference available also. In my application, AC is scaled from about +3V to about 0.3V with the zero at 1.65V, so the comparator input reference needs an equivalent offset.
Also nice to have, but not totally necessary, would be adjustable hysteresis ( CR0[HYSTCTR] = 00-11), pin reassignment for those needing to cram in other functions, and the interrupt capability of the comparators. This last thing can be done external to the chip if there are enough extra I/O pins for the application. I think the filter function is a nice to have also, but a simple R or RC is usually all that is needed for most apps.
Thanks for reading this, and I hope you have the time and energy to do this for us analog guys!!
Tim
(offgrid engineering)
P.S. I do know that an external 20 cent comparator (maybe 35 cents for two) can be added instead. But hey....it's already on-chip now!!! Seems crazy in this world of trying to reduce waste and energy to duplicate parts, right?!
Let me start by saying I am excited about the product, I've been a Freescale person since they were Motorola and used the early 6800 series, and watched them do what I think was the first ADC on the same die as the microcontroller. Very cool stuff at the time. Also, we were coding in assembly and sometimes BASIC, and FORTH...that is until C came along; thank heaven for that!
So now you build a nice micro soldered and tested on a super small USB board with a lightning fast core and peripherals and a 13-14 (effective) bit ADC....all for under 20 bucks! So far I have 3 of them, with plans on 10 more for my prototypes, and then about 1K per year, which in the PV solar business is pretty low volume. Why not spin my own controller? Easy: For that volume it is just not worth it. 10k/yr...that is another whole potato, for that I'd design my own controller, like we did at Trace, Xantrex, Outback, and Magnum before.
I've got a good part of my application going, but I still need use a good, fast, (and did I mention) cheap comparator. Comparators are often used for motor control/inverter/charger MOSFET power sections, where you need fast overcurrent detection to keep the power devices from letting the smoke out, or for very quick and consistent AC zero crossing detection to get accurate AC RMS samples and for grid synchronization. If your inverter does not sync perfectly with the grid, this is not a good thing!!
The Teensy 3.0 has two on-die comparators - CMP0 and CMP1. Would it be possible to have a few functions that use one or both of these? It would be helpful to have the DAC reference available also. In my application, AC is scaled from about +3V to about 0.3V with the zero at 1.65V, so the comparator input reference needs an equivalent offset.
Also nice to have, but not totally necessary, would be adjustable hysteresis ( CR0[HYSTCTR] = 00-11), pin reassignment for those needing to cram in other functions, and the interrupt capability of the comparators. This last thing can be done external to the chip if there are enough extra I/O pins for the application. I think the filter function is a nice to have also, but a simple R or RC is usually all that is needed for most apps.
Thanks for reading this, and I hope you have the time and energy to do this for us analog guys!!
Tim
(offgrid engineering)
P.S. I do know that an external 20 cent comparator (maybe 35 cents for two) can be added instead. But hey....it's already on-chip now!!! Seems crazy in this world of trying to reduce waste and energy to duplicate parts, right?!