Matrix Hairstyles MB XXX-3U - Manual (Page 11)

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3.4.6 Overshoot at Turn-on/Turn-off
The output voltage overshoot upon the application or removal of the input voltage, or the
assertion / deassertion of PWR_ON, under the conditions specified in Section 3.1, less
than 10% above the nominal voltage. There is a smooth and continuous ramp of each DC
output voltage from 10% to 90% of its final set point within the regulation band, while
loaded as specified in Section 3.3. The smooth turn-on requires that during the 10% to
90% portion of the rise time, the slope of the turn-on waveform is positive and have a
value of between 0 V/ms and [Vout, nominal] V / 0.1 ms. Also, for any 5 ms segment of
the 10% to 90% rise-time waveform, a straight line drawn between the end points of the
waveform segment must have a slope
≥ [Vout, nominal] V / 20 ms. No voltage of
opposite polarity present on any output during turn-on or turn-off.
3.4.7 Reset After Shutdown
If the power supply latches into a shutdown state due to fault condition on its outputs, the
power supply shall return to normal operation only after the fault has been removed and
the PWR_ON (or DC input) has been cycled OFF/ON with a minimum OFF time of 3
second.
3.4.8 +5VSB at AC Power Down
After AC power is removed, the +5VSB standby voltage output should remain at its
steady state value for the minimum holdup time specified in Section 3.3.6 until it begins
to decrease in voltage. The decrease shall be monotonic in nature, dropping to 0.0 V.
There shall be no other perturbations of this voltage at or following removal of AC power.
3.5 Output Protection
3.5.1 Over voltage Protection
The over voltage sense circuitry and reference shall reside in packages that are separate
and distinct from the regulator control circuitry and reference. No single point fault shall
be able to cause a sustained overvoltage condition on any or all outputs. The supply shall
provide latch-mode overvoltage protection as defined below.
Table 9: Overvoltage Protection
Output Min. Nom. Max. Unit
+12VDC 14.0 ----- 15.0 Volts
+5VDC 5.8 ----- 6.9 Volts
+3.3VDC 3.8 ----- 4.3 Volts
3.5.2 Short Circuit Protection
An output short is defined as any output impedance of less than 0.1 ohms. The power
supply shall shut down and latch off for shorting the +3.3VDC, +5VDC, +12VDC, -12V
rails to return or any other rail. The power supply will shut down and latch off .
The +5VSB must be capable of being shorted indefinitely, but when the short is removed,
the power supply shall recover automatically .
The power supply shall be capable of withstanding a continuous short-circuit to the
output without damage or overstress to the unit (components, PCB traces, connectors, etc.)
under the input conditions specified in Section 3.1.