When TEENSY 4.1 is powered off via ON/OFF pin, how much power is used.

rca4203

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The Title says it all
When TEENSY 4.1 is powered off via ON/OFF pin, how much power is used to allow it to detect the 0.5 sec power on signal?
 
Not recalling having seen that as measured ... suppose it keeps the related RTC unit powered so will be some small current ... maybe my new cheap meter can measure that ...
 
Not recalling having seen that as measured ... suppose it keeps the related RTC unit powered so will be some small current ... maybe my new cheap meter can measure that ...

Hmm, the RTC unit is optionally powered by a coin cell. The two features are not connected otherwise. Having the coin cell enhances the turn on according to the specs.

Sorry, but I am looking for a measure of current in micro or nano amps.
 
Desire is understood - not seen it called out as noted.

There is a low power section that controls the On/Off and it is AFAIK also related to the RTC section which is powered any time the unit has power.

The On/Off state is also maintained by RTC cell power - thus the assumption they are connected.

Just got back ... might see what new meter shows ...
 
Desire is understood - not seen it called out as noted.

There is a low power section that controls the On/Off and it is AFAIK also related to the RTC section which is powered any time the unit has power.

The On/Off state is also maintained by RTC cell power - thus the assumption they are connected.

Just got back ... might see what new meter shows ...

According to the specs, the RTC needs a coin cell type battery connected to VBAT to keep the RTC running after power OFF. By having that coin cell, the RTC date/time is maintained, and something called 'power state. Attached is a screen grab of the spec. The only info I can find is 0.02 mA which is crazy high for a deep sleep or better mode, some modern chips get down to nano amps.
Screenshot 2023-05-26 at 17.13.13.jpg
 
bare T_4.1

105.5 mA : running some sketch
0.26 mA : seconds after holding On/Off to GND

Same T_4.1

135.5 mA : running a simple print time with busy calc'ing RND number between seconds after programming
0.26 mA : seconds after holding On/Off to GND
112.1 mA : Off/On touch GND >> running a simple print time with busy calc'ing RND number between seconds after programming

NOTE: RTC time was indeed maintained while power supplied and in the OFF state - no RTC Battery in place.
 
According to the specs, the RTC needs a coin cell type battery connected to VBAT to keep the RTC running after power OFF. By having that coin cell, the RTC date/time is maintained, and something called 'power state. Attached is a screen grab of the spec. The only info I can find is 0.02 mA which is crazy high for a deep sleep or better mode, some modern chips get down to nano amps.
View attachment 31185

Never read much of the manual ... but there is a Low Power element to the MCU with some cute name. That element {in practice} is powered by the main power and runs RTC and maintains the On/Off state, as noted RTC Battery will do the same if main supply is removed.

Indeed 0.2 mA is a generous amount and as INSTALLED {there are inline diodes and perhaps other thingies taking some power including the LDO itself} where the book only knows of the ideal MCU power usage. {measure here is across 5V line in opened USB cable}

New cheapo meter is better - dial suggest current measure of 600, 60 mA or 60 uA ranges. So reading should be decent.
 
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