ACME Cape

Another Cute Measurement Equipment

DetailsBuy on Tindie

ACME Cape

The ACME concept

Fully open solution

The ACME initiative was launched, with the objective of getting rid of all these limitations of current proprietary solutions and providing the community with the most flexible low-cost but high-perf solution!

The proposed solution comes as an extension for the BeagleBone Black (the ACME Cape), designed to provide multi-channel power and temperature measurements capabilities to the BeagleBone Black (BBB). It comes with power and temperature probes integrating a power switch (the ACME Probes), turning it into an advanced all-in-one power/temperature measurement solution.

A scalable solution

Using a standard connector

The ACME initiative also proposes a new standard (free of charge) for power measurement connector (the ACME Power Connector), to solution the issue of development boards not being ready for power measurements.

The ACME initiative is completely open source, from HW to SW drivers and applications.

HW details

Main board ACME Cape RevB

Compared to the original version, the RevB improved the previous design to reduce the size, the cost and the usability.

  • The USB and Jack probe can be stacked together
  • The HE10 size was drastically reduced
  • A smaller connector replaced the previous one
  • Standard cable are usable instead of the previous custom one
  • Power switching is consistent between USB and Jack probe

INA226: Current / Power Monitor

All the probes contain a TI INA226 for the ADC conversion.

Measurements:

  • VBUS from 0 to +36V
  • VSHUNT from 2.5uV up to 81.92mV

Data reporting:

  • VBUS, VSHUNT, CURRENT AND POWER
  • High Accuracy measurements
  • 16-bit ADC
  • 2.5uV offset for VSHUNT
  • 1.25mV offset for VBUS
  • 0.02% Gain error typical
  • 140us conversion time minimum
  • On-board noise filtering

Other features

  • Calibration for optimum accuracy selection
  • Multiple measures averaging
  • Conversion time selection from 140us up to 8.244ms
  • Programmable ALERT interrupt for over/under limit values
  • Configurable operating mode
  • I2C 400KHz data transmission bus
  • 16 I2C address bus possibilities

HE10 Power Probe

6-pin HE10 header

  • 6A max current
  • 13mΩ contact resistance

3 possible current ranges

  • 0.005Ω for 1.5A < Current < 10A
  • 0.05Ω for 150mA < Current < 1.5A
  • 0.5Ω for 0 < Current < 150mA

2010 package, 0.5W max, 1% tolerance

USB Power Probe

Power Control

  • Power switching capability  through TPS22929

High precision resistor

  • 0.08Ω for Current up to 1A
  • 2010 package, 0.5W max, 1% tolerance

Jack Power Probe

Power Control

  • Power switching capability  through TPS22929
  • 6A current limitation
  • 20.5V transil for voltage protection

High precision resistor

  • 0.01Ω for Current up to 6A
  • 2010 package, 0.5W max, 1% tolerance

SW information

Custom Buildroot BBB Linux distribution

  • Upstream ACME HW drivers
  • Integrated with Sigrok SW Suite
  • Low-level HW interface
  • Command-line Interface, GUI front-ends
  • Upstream driver, Buildroot package available
  • Local (HDMI) & remote (vncviewer) use

sigrok-logo

Integrated with Xoscope

  • Digital oscilloscope Application
  • Added Sigrok support for data sampling
  • LCD Cape & HDMI output supported

More details about SW running on the ACME Cape is available on the following pages.

Where to buy ACME cape and probes

Buy on Tindie

I sell on Tindie