laurent wrote:On the top of my wishlist for a Pi Zero upgrade is there a BCM2836 or 2837 single core CPU instead of the BCM2835 old ARMv6 one, in order to have a better efficiency.
The actual Pi Zero draws a little power making it a good choice for solar or battery powered system. But drawing a little power for a long time is not that efficient.
A BCM2836 or BCM2837 with a single core and a frequency reduced to keep the same power consumption of the actual BCM2835 should offer a nice horsepower for battery or solar powered projects, for the same consumption.
I'm currently waiting for the incoming Pi 3 model A for that purpose.
BCM2836 is dead, that's why we have a Pi2B2 using 2837.
And the BCM2837 is just too power hungry for Pi0 type applications.
There is also a problem with RAM chips that can be easily and cheaply soldered -- POP works, the current 2836/7 packaging doesn't.
So, we need the next gen (28nm) SOC, and knowing how clever the folks at RPF and Broadcom can be, they will be designing (by now, possibly even testing) something that will work for both Pi4 and a low-speed low-power option (maybe even software selectable), or possibly two versions, single core for Pi0v2 (512MB POP RAM) and multi-core for high performance Pi4 (probably >1GB, non-POP RAM).
2836 is dead because the demand is too low to maintain the production. With a new product with it, the demand could raise up to justify to produce them again. I don't absolutely want to see a 2836, I just want to say that nothing is impossible.
2837 is too power hungry ? According to the number of cores and frequency of the Pi 3's one, indeed.
But if the cortex A53 has a better efficiency compared to the ARM11, it means that for a given equivalent power consumption, the A53 will beat the ARM11. So, a equivalent power consumption may just mean a reduced number of cores and frequency !
Like any other manufacturers, Broadcom may have some BCM2837 (or 2836) aren't capable of running all their 4 cores and/or their full frequencies (those are simply rejected).
Keep in mind that the Pi Zero targets the lowest price ! Harvesting previously rejected 2836/37 batches may be a low cost solution.
I remember to have already discussed about the POP package here and it wasn't such a problem. Technically it wasn't if I'm right, but after, it's harder to find a huge choice of POP memories.