I’m reaching out to gather community experiences regarding the RTC backup current on the Jetson Orin series (Orin Nano/NX).
According to the datasheet (Section 3.5 PMIC_BBAT), the current range is specified as 12µA to 50µA. That 50µA is the “maximum in worst case conditions” and that typical operation is closer to 12µA.
However, as we need to explain this to our customers and provide realistic battery life expectations, I would like to better understand:
What specific conditions or scenarios have you observed causing the RTC current to approach the 50 µA upper limit?
Some points I’m particularly interested in:
Temperature: Has anyone observed higher current under elevated temperatures (e.g., 85°C)? I recall some users previously speculated that 50 µA might be associated with high-temperature conditions.
I²C communication: Does active I²C bus activity on the RTC interface cause the current to increase significantly? A previous user asked this question but I don’t believe we received a clear answer.
Power state transitions: Are there any transient conditions (e.g., during power-up/power-down sequences) that cause spikes, or is the 50 µA value sustained only under steady-state backup conditions?
Module-to-module variation: Is there noticeable variation between individual modules, possibly due to manufacturing/process differences?
PMIC_BBAT pin load: The PMIC_BBAT pin is said to feed the power sequencer in the PMIC solution. Does this mean factors like system configuration or boot state could affect the backup current?
For context, we have performed our own measurements on two different carrier boards in a powered-off state (VDD_IN off, only battery supplying BBAT) at room temperature, after RTC initialization:
Board #1: ~16µA
Board #2: ~14.5µA
Both measurements are consistently close to the typical 12 µA value. However, we want to understand the boundary conditions that could push this to 50 µA.
Any shared measurement data, test conditions, or insights from your own designs would be greatly appreciated!
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The question is about the conditions that lead to 50 µA RTC current on the Jetson Orin Nano/NX series. According to the datasheet, the current range is specified as 12µA to 50µA, with 50µA being the maximum in worst-case conditions.
From the provided context, it is mentioned that the 50µA value represents the worst-case condition. However, there is no clear information on the specific conditions that lead to this value.
The community is asked to share their experiences and measurements regarding the RTC backup current. Some points of interest include:
Temperature: Has anyone observed higher current under elevated temperatures (e.g., 85°C)?
I²C communication: Does active I²C bus activity on the RTC interface cause the current to increase significantly?
Power state transitions: Are there any transient conditions (e.g., during power-up/power-down sequences) that cause spikes, or is the 50µA value sustained only under steady-state backup conditions?
Module-to-module variation: Is there noticeable variation between individual modules, possibly due to manufacturing/process differences?
PMIC_BBAT pin load: Does the system configuration or boot state affect the backup current?
The provided measurements on two different carrier boards show consistent values close to the typical 12µA value. However, the community is encouraged to share their own measurement data, test conditions, or insights to help understand the boundary conditions that could push the current to 50µA.
Unfortunately, the provided context does not offer clear answers to these questions. Therefore, I could not find clear support for the specific conditions that lead to 50µA RTC current in the provided Jetson Orin Nano documentation.
— We support team will also look into your issue to have further suggestions soon. please stay tuned. —
The RTC resides inside of the power sequencer of the module. The 12uA and 50uA specs apply to steady state current consumption.
The 50 uA max spec covers the maximum current across the power sequencer’s Tj range, which includes 85°C. The 12uA value applies to room temp.
I2C is inactive when the power sequencer is in the backup battery state.
There is a 4.8uF of capacitance on the module’s PMIC_BBAT so the current could exceed 50uA depending on the rate that the rail increases when voltage is applied.
This is already accounted for in the 50uA steady state spec.
The backup current is only consumed when the VDD_IN has been previously applied to the system and then VDD_IN was removed. So the system itself is not active and does not affect backup current in backup state. If PMIC_BBAT is applied but VDD_IN is never applied after that, the PMIC does not enter backup state.
