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Where a Power Reserve has been allocated to a Sink the Source shall
indicate the Power Reserve as part of every Source_Capabilities Message
it sends.
When the same Power Reserve is shared between several Sinks the Source
shall indicate the Power Reserve as part of every Source_Capabilities
Message it sends to every Sink.
When the Reserve is temporarily used by a GiveBack capable Sink the
Source shall indicate the Power Reserve as available in every
Source_Capabilities Message it sends.
When the Reserve is temporarily used by a GiveBack capable Sink, when
the Power Reserve is requested by another Sink, the Source shall return a
Wait Message while it retrieves this power using a GotoMin Message.
Once the additional power has been retrieved the Source shall send a new
Source_Capabilities Message in order to trigger a new request from the
Sink requesting the Power Reserve.
The Power Reserve may be de-allocated by the Source at any time, but the
de-allocation shall be indicated to the Sink or Sinks using the Power
Reserve by sending a new Source_Capabilities Message.
7.1.4 Positive Voltage Transitions
During the positive transition the Source shall be able to supply the Sink
standby power and the transient current to charge the total bulk
capacitance on Vbus.
The slew rate of the positive transition shall not exceed vSrcSlewPos.
The transitioning Source output voltage shall settle within vSrcNew by
tSrcSettle.
The source shall be able to supply the negotiated power level at the new
voltage by tSrcReady
The positive voltage transition shall remain monotonic while the
transitioning voltage is below vSrcValid min and shall remain within the
vSrcValid range upon crossing vSrcValid min.
At the start of the positive voltage transition the Vbus voltage level shall
not droop vSrcValid min below either vSrcNew or vSafe5V as applicable.
7.1.6 Response to Hard Resets
After establishing the vSafe0V voltage condition on Vbus, the Source shall
wait tSrcRecover before restoring Vbus to vSafe5V.
From the start of the voltage transition, the Source shall meet vSafe5V
max within tSafe5V and shall meet vSafe0V within tSafe0V.
7.1.8 Safe Operating Considerations
7.1.8.3 Over-Current Protection
Sources shall implement over-current protection (OCP) mechanisms.
The port level OCP mechanism shall not respond sooner than
tSrcOcPresent and the over-current condition on the port shall not be
present for more than tSrcOcPresent max.
7.1.9 Output Voltage Tolerance and Range
After a voltage transition is complete and during static load conditions the
Source output voltage shall remain within the vSrcNew limits.