Power Distribution#

Power Distribution Dependency#

The following diagram shows in which flow the rails (equals with signal names in the schematic) of the carrier board are powered.

            graph LR
    A(X14) -->|Reverse Polarity,<br>Overvoltage Protection| VIN{VIN}
VIN --> X15
VIN -->|U10, 3.3 V,<br>5.0 A max| 3V3_MOD
VIN -->|U11, 3.3 V,<br>5.0 A max| 3V3_PER
VIN -->|U12, 5.0 V,<br>5.0 A max| 5V_PER
VIN -->|U23, 1.8 V,<br>2.5 A max| 1V8_PER
5V_PER -->|U22, 1.8 V,<br>2.0 A max| 1V8_MOD
1V8_MOD -->|Jumper R128| VCCO_47
1V8_MOD -->|Jumper R129| VCCO_48
1V8_MOD -->|Jumper R133| VCCO_64
1V8_MOD -->|Jumper R131| VCCO_65
1V8_MOD -->|Jumper R136| VCCO_66
    VCCO_47 -.-> SoM((SoM))
    VCCO_48 -.-> SoM
    VCCO_64 -.-> SoM
    VCCO_65 -.-> SoM
    VCCO_66 -.-> SoM
    3V3_MOD -.-> SoM
    

Power-On Sequence#

There is a recommended sequence of powering up the Xilinx Zynq UltraScale+ MPSoC power domains. The SoM cares about the power-on sequence of their components such as Low-Power Domain, Full-Power Domain and memory. For more information see TE0808 Rechnical Reference Manual. The carrier board differs between power-on the Processing System (PS) and Programical Logig (PL) part of the SoM. The PS has to be powered-up before PL. Sequence Stage 1 starts with applying the 24 V power supply at X14 to rail VIN. Thus it powers up the SoM after 3V3_MOD is available (Stage 2). The SoM feedbacks with a “power good” signal PG_Module to enable the power supply for the PL (through 1V8_MOD).

        sequenceDiagram
        participant VIN
        participant 3V3_MOD
        participant 3V3_PER
        participant 5V_PER
        participant 1V8_MOD
        participant 1V8_PER
        participant SoM
        VIN->>+3V3_MOD: Stage 1
        VIN->>+3V3_PER: Stage 1
        VIN->>+5V_PER: Stage 1
        3V3_MOD->>+SoM: Stage 2
        SoM->>+1V8_MOD: PG_Module
        SoM->>+1V8_PER: PG_Module
        1V8_MOD->>+SoM: Stage 3