PAC5253
Power Application Controller
reinitialized. Only the persistent power manager status bits (resets and faults) are retained during hibernation.
10.3.5. Power and Temperature Monitor
Whenever any of the VSYS, VCCIO, VCC33, or VCC18 power supplies falls below their respective power good threshold voltage, a
fault event is detected and the microcontroller is reset. The microcontroller stays in the reset state until VSYS, VCCIO, VCC33
,
and VCC18 supply rails are all good again and the reset time has expired. A microcontroller reset can also be initiated by a
maskable temperature fault event that occurs when the IC temperature reaches 170°C. The fault status bits are persistent
during reset, and can be read by the microcontroller upon re-initialization to determine the cause of previous reset.
A power monitoring signal VMON is provided onto the ADC pre-multiplexer for monitoring various internal power supplies.
VMON can be set to be VCC18, 0.4•VCC33, 0.4•VCCIO, 0.4•VSYS, 0.1•VREGO, 0.1•VP, 0.0333•VHM, or the internal compensation
voltage VCOMP for switching supply power monitoring.
For power and temperature warning, a VP low event at 77% of the regulation voltage and an IC temperature warning event
at 140°C are provided as maskable interrupts to the microcontroller. These warnings allow the microcontroller to safely
power down the system.
In addition to the temperature warning interrupt and fault reset, a temperature monitor signal VTEMP = 1.5 + 5.04e-3 • (T -
25°C) (V) is provided onto the ADC pre-multiplexer for IC temperature measurement.
10.3.6. Voltage Reference
The reference block includes a 2.5V high precision reference voltage that provides the 2.5V reference voltage for the ADC,
the DACs, and the 4-level programmable threshold voltage VTHREF (0.1V, 0.2V, 0.5V, and 1.25V).
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Rev 1.24‒March 3, 2018
ACTIVE-SEMI [ ACTIVE-SEMI, INC ]
