Intel ATX - Timing, Housekeeping, and Control

Electrical
20 Design Guide
3.3 Timing, Housekeeping, and Control – Required
Figure 3-3: Power on Timing
Table 3-8: Power Supply Timing
Parameter Description
Value
Legacy
Timings
1
Required
Recommended
for ALPM
T0 AC power on time - <2s -
T1 Power-on time < 500ms < 200ms <150ms
T2 Rise time - 0.2 – 20ms -
T3 PWR_OK delay 100ms
2
– 500 ms 100ms
2
– 250 ms
100ms
2
–
150ms
T4 PWR_OK rise time - < 10 ms -
T5
AC loss to
PWR_OK hold-up
time
3
- > 16 ms -
T6
PWR_OK inactive
to DC loss delay
- > 1 ms -