cinderblock
Member
Hey all,
I'm wondering if anyone has an idea of the RTC battery current consumption when the rest of the teensy is completely unpowered. (I'm using a Teensy 3.2 currently but if someone has this information for the other chips, I'm sure someone would find it useful)
I'm trying to size a coin cell to keep the RTC alive for some period of time.
I have some measurements but I don't trust them as my meter's accuracy at such low levels is questionable at best. It also has like no resolution at that low range.
I've found the power consumption operating behaviors table from the K20 datasheet. However, it is not clear to me which numbers are valid for vbat. The two relevant rows:
I think it's pretty clear that the "with RTC [...] disabled" is not what I'm interested in. Is this just leakage current on VBAT when RTC is not running?
I'm guessing the "Average current when CPU is not accessing RTC registers" is the rating I'm interested in. However, the "when CPU is not accessing RTC registers" is unclear to me. Is this the datasheet trying to say, if VDD is unpowered, this is the expected draw on the RTC battery?
I'm wondering if anyone has an idea of the RTC battery current consumption when the rest of the teensy is completely unpowered. (I'm using a Teensy 3.2 currently but if someone has this information for the other chips, I'm sure someone would find it useful)
I'm trying to size a coin cell to keep the RTC alive for some period of time.
I have some measurements but I don't trust them as my meter's accuracy at such low levels is questionable at best. It also has like no resolution at that low range.
I've found the power consumption operating behaviors table from the K20 datasheet. However, it is not clear to me which numbers are valid for vbat. The two relevant rows:
I think it's pretty clear that the "with RTC [...] disabled" is not what I'm interested in. Is this just leakage current on VBAT when RTC is not running?
I'm guessing the "Average current when CPU is not accessing RTC registers" is the rating I'm interested in. However, the "when CPU is not accessing RTC registers" is unclear to me. Is this the datasheet trying to say, if VDD is unpowered, this is the expected draw on the RTC battery?