Forum Discussion
Honored ContributorIm curious why
Noone had any advice about running Cyclone II based boards off rechargeable batteries? Is there something I dont know where it's a bad idea?
25 Replies
Altera_ForumI haven't worked yet on battery powered FPGA system, but I would recommend that you try to keep the current consumption as low as possible in your design (being battery powered). When powering from a battery, you will also have to consider FPGA power up in-rush current requirements, which can affect more when the battery is partially drained.
- Altera_Forum
My needs for power are minimal (insert joke about me not really being evil here), the Cyclone II FPGA (144 pin type so I have a chance of soldering it). the EPCS chips, a few buttons, some small relays controling things from another bigger battery. It's just a toy/game prototype, so I'd rather carry extra batteries then build a 1.2v/3.3v warp drive.
This is my first PCB build and design, using PCB123 unless you know a better solution. I was a computer Engineer but never did much soldering, hoping the weller WES-51 I got may make it easier. - Altera_Forum
Hi Evil. I'm a bit surprised that nobody has come forward with a more helpful response on the power requirement question. I suppose it does depend a lot on the device you're thinking of using and what sort of external components you'll need. If the project is mostly for your own personal enjoyment and education then you should go ahead with it anyway.
My design uses an EP2C20F256 device with some external flash and SRAM for program memory (I'm using NIOSII). Apart from that I've got a few A/D converters, digital I/O etc. I tried to estimate the likely power consumption using the Powerplay feature of Quartus, but to be entirely honest it's going to be a bit of a 'finger in the air' approach. I'll let you know how I get on. In the meantime, good luck in your endeavours. Sharky - Altera_Forum
Thanks Sharky, it's going to be a toy/game thing, so I dont know If my idea will work with the cyclone II if the battery life will be short, I'm planning a "laser tag" sort of device pair. I found that national semi stuff on google, I may have to figure out which option of theirs to use.
So sounds like you work with this stuff, thats great. I just do it as a hobby since I was educated as an Engineer and enjoy it. Defense plants around here just want people who have been on the job with this stuff for 10 years. - Altera_Forum
Hi there. I saw your original post but had no particular advice to offer, so I didn't bother. However, I hate to see you neglected so here's my opinion.
I can see no reason why you can't run your Cyclone II system from rechargeable batteries. Depending on the device you use, I can imagine that the current drain could be pretty high. I am just about to get my first Cyclone II based prototype board back from the manufacturers and so I'm still feeling my way a bit with the power requirements. In order to derive the necessary core, PLL and I/O supply voltages from your battery I'd look at using a multi-output switched mode controller. A rep. from Arrow showed me a little evaluation board the other day for a Linear Technology device which occupied a very small board area and needed only tiny external components. I'm sure National Semi etc. will do similar devices. One other thought. If you haven't started your design yet, should you be looking at Cyclone III instead? Maybe others could comment.
