SilverStone SST-ST40NF [6/12] St40nf manual 5

4.3 OUTPUT TRANSIENT LOAD RESPONSE

4.4. PS_ ON#

DC Output Transient Step Sizes

summarizes the expected output transient step sizes for each output. The

transient load slew rate is = 1.0 A/µs.

PS_ON# is an active-low, TTL-compatible signal that allows a motherboard to remotely

control the power supply in conjunction with features such as soft on/off, Wake on LAN+,

or wake-on-modem.When PS_ON# is pulled to TTL low, the power supply should turn on

the five main DC output rails: +12VDC,+5VDC,+3.3VDC,and –12VDC. When PS_ON# is

pulled to TTL high or open-circuited, the DC output rails should not deliver current and

should be held at zero potential with respect to ground. PS_ON# has no effect on the

+5VSB output, which is always enabled whenever the AC power is present. Table lists

PS_ON# signal characteristics. The power supply shall provide an internal pull-up to TTL

high. The power supply shall also provide debounce circuitry on PS_ON# to prevent it from

oscillating on/off at startup when activated by a mechanical switch. The DC output enable

circuitry must be SELV-compliant.

Load-changing repetition rate of 50 Hz to 10 kHz

Ac input range per section 3.1

Capacitive loading per section 4.5

Output Max . step size

(amps)

Max. setp size

(% of rated output amps per Sec 4.1.1)

+12VDC

+5VDC

+3.3VDC

-12VDC

+5VSB

50%

30%

0.1A

0.5A

PS_ON# Signal Characteristics

Min. Max.

VIL, Input Low Voltage

IIL, Input Low Current (Vin = 0.4V)

VIH, Input High Voltage (lin = -200μA)

VIH OPEN circuit, lin = 0

0.0V

2.0V

0.8V

-1.6mA

5.25V

5. ENVIRONMENTAL REQUIREMENTS