As we predicted over the weekend, when we noticed a web ad for it that had been shown prematurely, the Raspberry Pi Model A+ has been launched today. The additional news is that it will sell for just $20.
After the Raspberry Pi B was upgraded to the B+ it was inevitable that the model A would follow. We were even promised something "special" in a recent interview.
Despite trying to keep it secret until today's official announcement by Eben Upton, Element 14, a major Raspberry Pi retailer, briefly published some details on Sunday by way of a web page getting ready to sell you a new model A+ and on the basis of this leaked info we were able to deduce that the A+ has acquired the same set of improvements that were introduced with the B+.
The board layout looks very different and it is much smaller than the model A or B+. Judging from the photograph, the A+ board just encompasses the four standard mounting holes which makes it 56x65mm - the model B+ is 56x86mm. The part of the PCB occupied by the USB and Ethernet sockets has been removed along with the network chip. The layout is essentially the same as the model B+ as you can see by comparing the photo with a model B+
The features of the A+ are listed as:
700MHz Broadcom BCM2835 CPU with 256MB RAM
40pin extended GPIO
1 x USB 2 ports
4 pole Stereo output and Composite video port
Full size HDMI
CSI camera port for connecting the Raspberry Pi camera
DSI display port for connecting the Raspberry Pi touch screen display
Micro SD port for loading your operating system and storing data
Micro USB power source
Smaller board footprint and is fully HAT compatible
Stream and watch Hi-definition video output at 1080P
Combined 4-pole jack for connecting your stereo audio out and composite video out
In this video Alex Eames provides a full walkaround and shows the A+ in action:
Following the official announcement we now know that the key improvement is indeed the new 40-pin GPIO socket, which makes the model A+ fully compatible with the HAT expansion standard. This means that any new HAT expansion cards should now work with the A+. It also specifically has a connector for the, as yet unannounced, Raspberry Pi touch screen. This was partially demoed in a recent interview and marked as "coming soon".
Another welcome change is the micro SD port, but the new A+ still has only a single USB 2 connector. The launch announcement confirms that device's power consumption is 25% lower than the A or 45% less power than the B+, which is roughly what we had guessed because it is basically the same design minus the Ethernet chip. Even so a current consumption of 200mA still makes some battery operation difficult.
The third improvement inherited from the B+ is better audio thanks to the audio circuit incorporating a dedicated low-noise power supply.
The only point on which we were wrong was with the price - of which we said:
it would be a big surprise if it wasn't $25.
The price tag has been set at just $20 (plus taxes), which certainly makes the model A+ good news, except of course for all those Raspberry Pi case makers who will now have to redesign their model A cases.
Perhaps now the model A costs about the same as a book, a few coffees or beers it will become the success that the A never was.
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