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Dear team,
Customer has questions on how to measure the assumption of SN74AUP2G08.
From the datasheet, I see ICC 0.9uA as static power assumption, so can I regard this ICC as the assumption when work in steady state?
Also I calculated delta ICC for PT(transient power assumption), nearly 7uA for customer's application. So do you have method to measure this transient power assumption?
From datasheet, I see delta ICC about 40uA, so can I regard this value as a sum of PT, PLC and PLR?
I am not sure if the accuracy of multimeter is not enough(0.1uA), they measured the ICC is 0uA in steady state. They hope you could share some ways to measure the steady assumption and transient assumption.
Thanks.
Best regards,
Sammi
ΔICC specifies what happens when the input signals that are not at the rails (as shown in the test conditions). This usually does not happen during normal operation when the input signals are driven by other logic devices at the same power supply voltage.
The power consumption can be computed from ICC and Cpd; see [FAQ] How do I Calculate Power Consumption or Current Consumption for my CMOS Logic Device?
Hi Clemens,
Thanks for your reply. Could you show how to use the equipment to test ICC when in work in steady state?
Best regards,
Sammi
Please note that 0.9 µA is the worst-case value at extreme temperatures; the actual current might be about 0.3 µA.
Measuring such small currents is not easy. If you do not have an amplifer like the µCurrent or tinyCurrent, you can put a shunt resistor in series with VCC and measure the voltage drop over that. You probably need a 1 MΩ resistor, and have to adjust the result for how the input impedance of your multimeter affects the measurement. (A power supply with remote sense inputs would be helpful to keep the voltage a the device at the desired level.)
Hi Clemens,
Thanks for your response. It is very clear. Per discussed with customer, we are still confused about the delta Icc test condition. Could you kindly give more details description about this parameters? Or real application or scenery that could cause this is also OK for us.
Thanks.
Best regards,
Sammi
See section 4.6.28 of Understanding and Interpreting Standard-Logic Data Sheets. Usually, ΔICC makes sense only for 5 V devices. (Sometimes, you do want to input a signal with a lower voltage, but then it's likely to be an analog signal that needs Schmitt-trigger inputs.)