Power
Jetson AGX Xavier Series Product
DG-09840-001_v2.5 | 29
voltage level within 0.5V of nominal when large current changes occur, then either the supply
may need to be improved or it may be necessary to modify the DV/Dt circuit. Supply changes
could include:
Improve supply to respond better to large fluctuations in power. If the improvements keep
any droops to less than ~0.5V, the DV/Dt circuit may work as intended and provide the most
margin for proper power-down sequencing during sudden power loss cases. This solution
is highly recommended over making modifications that compromise the DV/Dt circuit.
Use a higher voltage. Jetson AGX Xavier supports from 9V to 20V on the SYS_VIN_HV input.
The higher the voltage used, the lower the current at the input. When large power changes
occur during heavy computational loads, the effect on the supply voltage will be lowest
when the input voltage is near the maximum.
Modifications to the DV/Dt circuit include two options shown in Figure 5-12.
Remove the resistor in series with
VDDIN_PWR_BAD_N
which would disable completely the
DV/Dt circuit. This would mean that during a sudden power removal case, the input supply
voltage would have to drop to the level that would trigger the VIN loss detection circuit (see
Section 5.6.1 “Power Loss Detection”) which is ~7V to 8V. This change would remove all
benefits of the DV/Dt circuit and make it more difficult to meet power-off sequencing
requirements during sudden power removal cases. This should be a last resort fix.
Add an additional diode in the path from VDD_SRC to the Emitter to allow for more voltage
droop before triggering the DV/Dt circuit and shutting down the system. By default, the
droop allowed is ~0.5V. By adding one diode, an additional 0.6V-0.7V droop would be
allowed. This will reduce the benefit that the DV/Dt circuit provides and should be avoided
if possible or kept to a minimum (one additional diode).
