BUS PIRATE: Love the USB C connector!

Bus Pirate prototype Ultra v1b uses a common, cheap USB C connector and we are in love!

Micro B connectors are a nightmare. Very inconsistent footprints, poor materials and build quality, and very weak mounting supports. Often the leads are hidden under the housing and conceal pesky shorts. Almost every Micro B connector we hand soldered eventually broke off the board and usually took some traces with it.

USB C solved all these issues! Soldering it is an absolute breeze. Leads are easily accessible and friendly to solder. It’s made of decent materials, and the footprint seems to be pretty standardized across the market. The mounting posts are solid and strong, this connector isn’t going anywhere.

Here’s how we connected it on the v1b hardware. The footprint was made by Sjaak at SMDprutser and is in our git repo.

App note: FPGA power supply considerations

App note from Vishay Siliconix, giving us tips on powering FPGAs. Link here (PDF)

An FPGA is a device that offers many logic elements – up to 1 million gates in a single device at this writing – as well as other functionality such as transceivers, PLLs, and MAC units for complex processing. FPGAs are becoming very powerful, and the need to power the devices effectively is a key, if often underestimated, part of the design. A straightforward power supply design process can significantly reduce the number of required design iterations for the OEM designer.

PROTOTYPE: Bus Pirate “Ultra” v1b

Today we finished stuffing the first Bus Pirate “Ultra” v1b board. This includes the updates we posted this week, and a few other improvements from v1a:

The new power supply and voltage measurement concept are both tested and working on the new hardware. The new USB C connector is extremely solid and is a dream to solder, we’ll never look back.

Next we’ll work on getting the display going. So far it powers up and no smoke escapes.

Eagle files for v1b are in the git repo. Follow development of v1c in the forum.

Bus Pirate: Reclaiming the Vpullup pin

The Bus Pirate Vpullup pin supplies a voltage to the on-board pull-up resistors. In the “Ultra” hardware it also powers the external half of the bi-directional IO buffer.

  1. MOSI
  2. CLOCK
  3. MISO
  4. CS
  5. AUX
  6. AUX2 (formerly ADC)
  7. Vpullup
  8. AUX4 (formerly 3.3Volts)
  9. 0.8-5.0Vout (formerly 5.0Volts)
  10. GND

So far we’ve added voltage measurement to every IO pin and removed the dedicated ADC pin. We also replaced the fixed 3.3volt and 5volt power supplies with a single programmable output power supply (Vout) capable of 0.8-5.0volts output at 300mA. Today we’re going to reclaim the Vpullup pin and dig into the on-board pull-up resistor system.

Continue reading “Bus Pirate: Reclaiming the Vpullup pin”

BUS PIRATE: 0.8-5.0volt programmable output power supply

  1. MOSI
  2. CLOCK
  3. MISO
  4. CS
  5. AUX
  6. AUX2 (formerly ADC)
  7. Vpu
  8. 3.3V
  9. 5.0V
  10. GND

After adding buffered voltage measurements to every IO pin, we eliminated the dedicated ADC pin and turned it into a general purpose IO (AUX2). Now we’re going to take a hatchet to the on-board voltage regulators (3.3V, 5.0V) and replace them with a robust programmable output power supply.

Continue readingBUS PIRATE: 0.8-5.0volt programmable output power supply”

BUS PIRATE: Voltage measurement on every pin

Bus Pirate Ultra v1a follows the same pinout as previous Bus Pirates. 5 I/O pins (MOSI, CLOCK, MISO, CS, AUX), a voltage probe (ADC), a voltage source for the on-board pull-up resistors (Vpu), two power supplies (3.3, 5.0volts) and ground. While we were building the prototype it became obvious that a few tweaks could make a much more useful tool.

  1. MOSI
  2. CLOCK
  3. MISO
  4. CS
  5. AUX
  6. ADC
  7. Vpu
  8. 3.3V
  9. 5.0V
  10. GND

This is the starting pinout. In this post we’ll update the voltage/ADC probe to measure voltage on every IO pin, and free up a pin for general purpose use.

Continue readingBUS PIRATE: Voltage measurement on every pin”

DIY wireless temp/humid/pressure sensors for measuring vacuum sealed 3D printed filament containers

Scott M. Baker writes:

I made some wireless sensors, using BME280 temperature, humidity, and pressure sensors, together with SYN115 transmitter modules. I used these to verify the storage of vacuum sealed “PrintDry” 3D filament storage containers.

See the full post on his Scott M. Baker blog.

Check out the video after the break.

Continue reading “DIY wireless temp/humid/pressure sensors for measuring vacuum sealed 3D printed filament containers”

App note: Inductive switching for dual 24 and 36 V High-side switch families (XS4200 and XSD200)

Another app note from NXP describing the behavior of the SMARTMOS Dual 24 – 36 V high-side switch devices, at switch OFF when driving inductive loads. Link here (PDF)

These intelligent high-side switches are designed to be used in 24 V systems such as trucks and busses (XS4200). They can be used in industrial (XSD200) and 12 V applications as well. The low RDS(on) channels can control incandescent lamps, LEDs, solenoids, or DC motors. Control, device configuration, and diagnostics are performed through a 16-bit SPI interface, allowing easy
integration into existing applications.

App note: Repetitive short-circuit performances of the MC12XS6 IC’s family

App note from NXP about the short-citcuit protection strategies of their MC12XS6 centralized automotive lighting drivers family IC. Link here (PDF)

The MC12XS6 devices include up to five self-protected high-side switches, with its extended protection and diagnostics, to detect bulb outage and short-circuit fault conditions. Additionally, this device incorporates a pulse width modulation control module, to improve lamp lifetime with bulb power regulation at no less than 25 Hz, and address the dimming application (daytime running light).

Pogo pins + laser cutter = test fixture

Eric Gunnerson made this DIY pogo-pin test jig:

I decided to build a pogo-pin test jig, and since the approach I came up with was different than the other approaches I’ve seen I thought it would be worth sharing. I’m going to be targeting my laser cutter for fabrication, though I could have chosen to use my 3D printer instead.

See the full post on Eric’s Arcana and RiderX blog.

Check out the video after the break.

PROTOTYPE: Bus Pirate/Logic Analyzer with Ice40 FPGA

Bus Pirate “Ultra” taps an iCE40 FPGA to power a combined Bus Pirate interface and logic analyzer that is infinity hackable. Previous Bus Pirates relied on the hardware peripherals available in a microcontroller, which vary in features and have the occasional bug. With an FPGA we can implement practically any peripheral with all the fixes and hacks we want! SPI, I2C, UART, CAN? Yes! Master or slave? Both! Complex frequency generator? Yup! Full featured JTAG debugger? Don’t see why not!

A big STM32F103ZE (1) microcontroller connects to an iCE40HX4K FPGA (2) through a 16bit bus that can move a ton of data. The fully buffered interface (3) is capable of high-speed signaling from 1.2volt to 5volts. 128Mbit of RAM (4) powers a logic analyzer with a potential maximum speed over 200MSPS. A 32Mbit flash chip (5) stores up to 30 bitstreams with different features that can be loaded into the FPGA by the microcontroller.

This post covers our most recent hacks to the Bus Pirate, created with these goals in mind:

  • Peripherals that work and can be hacked
  • Direct interfacing at all common voltage levels
  • Real-speed bus activity
  • Built-in logic analyzer
  • Plenty of space for updates

Continue below to read about the design, or jump to the forum to see the bleeding edge.

Continue reading “PROTOTYPE: Bus Pirate/Logic Analyzer with Ice40 FPGA”

How to design and build your own Lithium battery pack

Adam Bender posted detailed instructions of how to design and build a custom DIY lithium battery pack with 18650 cells:

Designing a custom lithium battery pack is a fun way to learn about electricity and engineering. Lithium batteries can be used for countless applications including electric bikes, scooters, vehicles, backup power suppliers, off the grid solutions, and much more.

More details on Adam Bender’s blog. See part one of this series for the battery build.

Check out the video after the break.

App note: Orientations and Rotations

App note from Kionix on the introduction of most common method in determining orientation and rotations in an accelerometer. Link here (PDF)

The fact that accelerometers are sensitive to the gravitational force on the device allows them to be used to determine the attitude of the sensor with respect to the reference gravitational vector. This attitude determination is very useful in leveling or gimballing gyroscopes and magnetometers for use in compass and navigation instruments; determining tilt for game controller applications; and determining tilt or rotation for screen rotation of handheld devices. The method for calculating orientation or rotation depends on the specific application.

#FreePCB via Twitter to 2 random RTs

Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week:

  • Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

FM stereo radio receiver with RDS

Dilshan Jayakody has published a new build:

This tuner circuit is a quick prototype which I build to test the RDA5807M FM radio tuner IC. RDA5807M is a single-chip tuner IC with RDS and MPX decoder, and it equipped with I2C interface for control.
This receiver builds around Atmel’s ATmega16A 8-bit MCU. The output stage of this design consists of AN7147N, 2×5.3W audio power amplifier.

See the full post on his blog.

App note: Paralleling eFuses

ON Semiconductors guide to cover much higher current capacity from eFuses. Link here (PDF)

The standard 12 V, 5 V and 3.3 V electronic fuses from ON Semiconductor provide overcurrent and overvoltage protection and come in different current limit configurations. As an example, the 5 V NIS5452 eFuse has a recommended operational 5 A current limit. Sometimes the operating current for the user system might be much higher than the maximum allowed current limit provided by the eFuse.

App note: How to prevent thermal issues with high output current DC to DC converters in portable applications

Tips and tricks from ON Semiconductors on how to optimize high output current switching regulators thermal dissipation. Link here (PDF)

As power demand in portable designs is more and more important, designers must optimize full system efficiency in order to save battery life and reduce power dissipation. Energy losses study allows knowing thermal stakes. Due to integration and miniaturization, junction temperature can increase significantly which could lead to bad application behaviors or in worst case to reduce components reliability.

App note: High-power emitters for illumination applications

App note from OSRAM on High-power LEDs and their special requirements. Link here (PDF)

In general high power emitters can be driven with DC currents in the range of 1 Ampere whereas most low power products like 5 mm Radials are limited to 100 mA.

As the light output increases with driving current the optical power is raised by a factor of ten compared to standard devices. At the same time much less board space is occupied as fewer devices are needed. On the other hand a careful thermal management is absolutely mandatory because the thermal power dissipation is increasing in the same way as the optical output power. To keep the junction temperature of the chip as low as possible a low thermal resistance is needed and the standard FR4-PCB has to be replaced by a metal core PCB. By this a high optical efficiency of the IRED can be achieved.

Low cost high accuracy STM32 FFT LCR meter

Adil Malik made a low cost FFT LCR meter with an STM32 MCU:

The approach I took was a mixed signal one where a capable analog front end would be paired up with a beefy DSP processor to compute the Impedance. Most importantly, in this scheme, the DSP is responsible for discriminating the phase between the sampled voltage and current waveforms; this approach is preferred because it leads to good accuracy and calibration stability.

See the full post on his blog.