The new Cypress Pioneer Kit single board computer has come out offering just about anything a maker would want on one board. It runs a 32-bit ARM CPU on one chip, and a 32-bit microcontroller on a second chip. The microcontroller has all of the functionality one would hope for: 36 GPIO, 4 timers, serial comms, with the added bonus of programmable analog, programmable digital, and capacitive sensing capabilities. The ARM chip offers high speed (67MHz) computing, USB access, and additional GPIO available to users. The board itself includes a couple handy extras like a capacitive sensing slider input and an RGB LED.
But the real differentiator in this kit are the programmable analog components. But are they worth it? First off, the Pioneer can be had for a mere $25, making it even cheaper than the Arduino Uno when the cost of a shield, op amp, and peripheral components are added in order to have some analog functionality. Also, the sleek nature of having a single board computer can be maintained when trying to support a few simple analog functions that can be set by code. So it seems like a useful, cost-effective, unique feature; but how will it stack up for real-world uses?
The first question to ask is if the analog components even worth using. One would hope that they didn't do something silly like put an op amp that requires 2V of output headroom in a 5V system, making it only functional from 2-3V! Below is a comparison between the analog blocks of the Cypress 4200 series (in high power mode with a 5V supply) and the TLC2272 op amp. (Note: the TLC2272AIDR is a standard op amp that I usually have sitting around the bench and use for random jobs thanks to it being rail-to-rail, unity-gain stable, well-characterized, and operates on 5V and +/-5V).
Analog Performance Comparison | ||
Specification | Cypress 4200 MCU | TLC2272AIDR Op Amp |
Quiecient Current, typ. | 1mA | 2.2mA |
Gain Bandwidth (GBW) | 6MHz | 2.2MHz |
Max Output Current (Iout_max) | 10mA | 25mA |
Input Voltage Headroom (Vin) | 200mV | 900mV |
Output Voltage Swing (Vout) | 0.2V – (Vdd – 0.2V) | 0.09V – (Vdd – 0.35V) |
Input Offset Voltage (Vos), max | +/-1mV | +/-0.95mV |
Input Offset Voltage Drift, typ | +/-3uV/*C | +/-2uV/*C |
CMRR, typ | 80dB | 75dB |
PSRR, typ | 85dB | 95dB |
Noise, 1kHz, typ | 72nV/rtHz | 50nV/rtHz |
Slew Rate | 6V/uSec | 3.6V/uSec |
Based on these specs, the programmable op amp blocks included in the 4200 design will do a great job with competing with stand-alone devices. What sort of designs would need analog inputs? Gaining up an audio signal, or accurately measuring any signal that may be close to ground are a couple of examples. Now that it looks like a reasonable part, time to start building to uncover the real power of the programmable feature! Of course, since this is a new platform a new user might not find many projects to explore the system with. Thankfully Element14 has announced 100 projects in 100 days to put some designs out there and get people playing!