I'll try to keep it short, I'm interested in measuring the current draw of various microcontrollers (and associated sensors) during various stages of activity. During high activity stages with things like WiFi or Bluetooth active, they can easily reach 200 or 300mA, so I need to be able to measure these high currents. On the other hand, when put into deep sleep mode, some can drop to single digit uA, which I would like to be able to measure with at least 0.5uA precision.
I could use a shunt, but those aren't well suited to a large range of currents, the accuracy would be poor at low currents and the voltage drop would be significant at high currents.
I could use a feedback ammeter, but those typically can't handle more than 20 or 30mA.
I could use a hall effect current sensor, but I haven't found any designed for less than a few hundred mA.
Any suggestions would be appreciated.
As a final note, I do not have access to, nor money to acquire, expensive test equipment, so while I'm well aware that a normal, lab grade DMM could do exactly what I'm asking for, that's not an option for me.
#Edit:
I should have clarified, I need to be able to measure high and low currents without swapping out shunts or removing power in any way, as that would reset the mcu and I wouldn't be able to watch the current as it flips back and forth between sleep and high activity.
I really am looking for a magic solution here, which I realize may not exist, but that's why I'm asking the experts, I figure if anyone would know, it'd be the people on this forum.
I could use a shunt, but those aren't well suited to a large range of currents, the accuracy would be poor at low currents and the voltage drop would be significant at high currents.
I could use a feedback ammeter, but those typically can't handle more than 20 or 30mA.
I could use a hall effect current sensor, but I haven't found any designed for less than a few hundred mA.
Any suggestions would be appreciated.
As a final note, I do not have access to, nor money to acquire, expensive test equipment, so while I'm well aware that a normal, lab grade DMM could do exactly what I'm asking for, that's not an option for me.
#Edit:
I should have clarified, I need to be able to measure high and low currents without swapping out shunts or removing power in any way, as that would reset the mcu and I wouldn't be able to watch the current as it flips back and forth between sleep and high activity.
I really am looking for a magic solution here, which I realize may not exist, but that's why I'm asking the experts, I figure if anyone would know, it'd be the people on this forum.
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