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Raspberry Pi RP2040 Silicon sells for only $1

We are excited to announce that the Raspberry Pi RP2040 is now available in single-unit quantities for only $1 per chip, allowing you to build your own projects and products on Raspberry Silicon.

 

RP2040 - 500 Chips on 7" Tape RP2040 - 500 Chips on 7" Tape

 

RP2040 - 3400 Chips on 13" Tape RP2040 - 3400 Chips on 13" Tape

 

RP2040 - 10 Chips on Cut TapeRP2040 - 10 Chips on Cut Tape

 

 

RP2040 is our idea of the perfect mid-range microcontroller, this Raspberry Pi Silicon chipset is based on years of Raspberry Pi using other vendors’ devices in their own products and projects.

 

It stands out in three key ways:

 

  • Two fast CPU cores. A pair of ARM Cortex-M0+ cores, clocked at 133 MHz, provide ample integer performance. Use one core to run application code, and the other to supervise hardware; or run application code on both cores with FreeRTOS or MicroPython.

 

  • Plenty of RAM. With 264KB of RAM, you can concentrate on implementing features, not optimising your application for size. A fully connected switch connects ARM cores and DMA engines to six independent RAM banks, allowing you to squeeze every last drop of performance out of the system.

 

  • Flexible I/O. We provide all the usual interfaces: hardware UARTs, SPI and I2C controllers, USB 1.1, and a four-channel ADC. But it’s the programmable I/O (PIO) subsystem that makes RP2040 stand out, enabling software implementations of protocols including SDIO, DPI, I2S, and even DVI-D.

 

All of this is packed into 2 mm² of 40 nm silicon, in a 7×7 mm QFN56 package.

 

RP2040 Microcontroller.
RP2040 is a low-cost, high-performance microcontroller device with flexible digital interfaces. Key features:


• Dual Cortex M0+ processors, up to 133 MHz

• 264 kB of embedded SRAM in 6 banks

• 30 multifunction GPIO

• 6 dedicated IO for SPI Flash (supporting XIP)

• Dedicated hardware for commonly used peripherals

• Programmable IO for extended peripheral support

• 4 channel ADC with internal temperature sensor, 0.5 MSa/s, 12 bit conversion

• USB 1.1 Host/Device

 

Raspberry Pi 2040 Schematic

 

 

What will you use your $1 Raspberry Pi RP2040 for?

Anonymous

  • Need help on connecting extra memory to store photos.
    Need 256Mbytes of extra storage. Which is economical option ?

    bigger than W25Q16 QSPI flash


    SD Card

    USB

  • in reply to scottiebabe

    If I ever get one in the right place I don't tempt fate by poking it

     

    (I have a real reflow oven now so I can't see them dancing any more )

     

    MK

  • in reply to Jan Cumps

    Well, until the solder melts.

     

    Yes the QFN comes with a mixed bag of emotions for me. But, eventually with hot air there is that moment when the package jumps into perfect registration sometimes with a little dance . You can lightly tap the corner with tweezers and it jumps right back.

  • in reply to scottiebabe

    Scott, the difficulty with pretinning is that the IC won't sit flush on the board.

    It increases the chance that the iC will fly away wile using the hot air pencil.

    Pretinning pads works for me, if I soak the area in flux and have the solder melted before placing the package.

     

     

    Then again, hand soldering is a very personal activity, so techniques that work for A may be finicky for B.

  • in reply to michaelkellett

    I am impressed with your soldering abilities!

     

    Personally, I have had the most success pretining the lead frame pads by drag soldering the iron across the chip then hot air soldering it on the board. Versus trying to bring the solder up from the board to the chip, but everyone's story will be different.

     

    Of course solder tries to resist crossing the air gap when you actually want it to bridge from the pad to leadframe lol.

     

    Still, well done hand soldering a QFN!

  • in reply to scottiebabe

      wrote:

     

    QFNs with a thermal pad are even more difficult than just a basic QFN.

    That's why you put holes through the board in the pad.

    For table top assembly they do several things:

     

    Allow the excess solder paste to escape (if you use paste - I don't on the centre pad - easier to use an iron from the back.

    Allow you to get heat in from the bottom with a big iron to solder the pad if you need to

    Allow you to get a need point probe in to check that the pad is soldered.

     

    Soldermask between the outer pads won't help you if you are using an iron - there is nothing on the chip itself.

    You need the whole thing swimming in flux !

     

    MK

  • Luckily for an extra $3 you can buy a PI Pico which is tested and guaranteed to function.

     

    This chip would be challenging to hand solder to say the least. I would only attempt with hot air. QFNs with a thermal pad are even more difficult than just a basic QFN. Additionally this is a 0.4mm QFN so the lowest cost PCB fab services won't even give you soldermask between the pads. 

  • in reply to Problemchild

    You can hand solder them - it's not ideal but is possible.

     

    Make a footprint with holes in the big centre pad and don't flow ground plane into the centre pad.

    Make the pads on the board stick out beyond the chip by at least 0.5mm.

    Use a bit of springy steel wire held in a vice or "third hand" thingy to hold the chip down on the board in the right place.

    Use very fine solder (this is good: https://www.rapidonline.com/Catalogue/Search?tier=Solder&Attributes={%22Leaded%20/%20Lead-Free%22:[%22Leaded%22],%22SWG%…  )

    and lots of runny flux (this is good https://www.rapidonline.com/warton-metals-future-315-low-residue-no-clean-flux-500ml-bottle-87-0728 )

     

    Solder the outside pads with a very fine tip iron. If pads short together then just clean up with solder wick.

     

    It's much easier to put solder paste on the board with a pin (don't worry if it bridges outer pads together) but don't put much on the centre pad (and don't forget those holes !!!).

    You can heat it on a hotplate or, if you have nothing else, a thick bit of aluminium on the top of the cooker.

    Either way watch carefully as the solder heats up and when it melts remove the board from the ally plate.

     

    If pads short, now problem, clean up with flux and soldering iron (and maybe solder wick).

     

    The ultra fine solder is a horrific price - I've been using the same reel for 10 years - it lasts a long time.

    If anyone fancies a try at this I'll send them a bit of solder if they send me a self adressed and stamped envelope. (contact by email - it's in my profile)

    The price is you have to post pictures of your efforts.

    I can't send flux

     

    I've done hundreds of chips like this - it's a pain but possible.

     

    If you are ordrering custom boards a stencil for solder paste is quite cheap but hard to use without a reasonable frame to hold it.

    Solder paste is expensive as well - and it has a short shelf life.

     

    MK

  • in reply to Problemchild

    Fair point. As long as it’s not bga.

  • in reply to raspberrypitechguy

    I'm sure the package wouldnt of effected it too much, I suppose that it was never really meant for hand soldering