Member #225064

Member Since: May 12, 2011

Country: United States

  • An arc can be sustained at around 50V for a 9.5mm gap (see "DC-Arc Models and Incident-Energy Calculations" published in IEEE). Even for a "low" voltage system, higher transient voltage across a gap can be created if there is sufficient inductance (VL = L dI/dt) and this will be enough to initiate an arc. But I agree, a sustained arc is less likely or impossible when the DC voltage is low enough. Just be aware that DC systems above some minimum voltage (perhaps 40V?) are not properly protected by a fuse with only an AC voltage rating.

  • The contents of the CHIPREV register (at address location: 0x4002000C) indicate 0x000ECF12. This corresponds to revison A1 per table 138 of the Aug. 2019 datasheet. Both artemis nano boards also give this for the CHIPPN register: 0x06671198. Table 1498 (footnote 1) indicates that "The silicon revision is identified by the first letter in the bottom row of the package's top marking: C = revision A1, F = revision B0." But the metal shield covering the chip prevents me from reading the top marking.

  • Please, for the safety of people who look to Sparkfun for sound reference designs, this kit should not be sold as a DC fuse when the socket is for an AC fuse (as pointed out above the kit even inculdes an AC fuse!). This may be a little known fact but it is worth pointing out here: it is not safe to use an AC fuse to protect for DC over current. Instead a DC rated fuse must be used for DC. A common form facor for a DC rated fuse is the blade style fuse commonly used in automotive.

  • When did B0 start shipping? I have 2 nano Artemis boards from batch #122745 and they both appear to be revision A1 (both were purchased Sept. 30th from Digi-Key). Will it be possible to determine silicon revision of the product being ordered prior to ordering these in the future?

  • What silicon revision is currently used on boards that have Artemis modules?

  • Any help with the following would be much appreciated. - How many charge-discharge cycles can this pack handle before capacity degrades significantly? - What lithium ion battery chemistry is used? - Is there a minimum load requirement for this pack to operate? Packs like this usually have an internal dc-dc converter that steps the approx. 4V from the battery up to 5V delivered to the output. Does this dc-dc converter remain on even when the load is very small, e.g. 50uA? - Can the four-tier status LED be disabled to conserve power? - Does the pack have current limiting and/or short circuit protection? How will this pack respond if I (inadvertently) apply more than the 1A rated load? Will it survive?

  • The correct form is: analogReference(AR_EXTERNAL); There needs to be an AR_ prefix attached to the various analog reference modes.

  • Does this board support an external analog reference when using the Arduino IDE? When I try the following: analogReference(EXTERNAL); I get an error: "invalid conversion from 'int' to 'eAnalogReference"

  • spelling correction: Philips (not Phillips)

  • Which inverter was chosen for this system? Kudos to SparkFun for plugging into the sun.

No public wish lists :(