l6611 STMicroelectronics, l6611 Datasheet - Page 20

• Manufacturer Part Number: l6611
• Description: Digitally Programmable Secondary Housekeeping Controller
• Manufacturer: STMicroelectronics

L6611
3
The time intervals t1-t5 are listed below
– t1: UV/OC blanking of MFAULT. While Main outputs are ramping up, the UV comparators are blanked
– t2: PW-OK delay. This period starts when all monitored outputs and AC sense are above their respec-
– t3: PS-ON debounce period. The voltage on PS-ON must be continuously present in a high or low state
– t4: Tdelay. The time from PS-ON being recognized as going high to MFAULT going high. This is to
– t5: UV blanking of DFAULT. During initial power up a period of UV blanking is applied to DFAULT as
Figure 18. Normal Operation Timing Diagram (ON/OFF with PS-ON or the AC power switch).
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AC
Vdd
Vdd-ok
UVBdfault
ACsns
PS-ON
Mfault
Main
OPs
POK
UVBmfault
for this interval to prevent a false turn-off. No such blanking is applied to OV faults.
tive UV levels and finishes at PW-OK going high.
for a minimum period for that state to be recognized.
provide a power down warning. When PS-ON requests power off, PW-OK goes low immediately.
soon as Vdd to the chip is in the correct range. No such blanking is applied to OV faults.
NORMAL OPERATION TIMING DIAGRAM (FIG. 18)
On
Off
Off
On
Vdd(on)
t5
ACsns_high
t1
t2
t3
t4
t3
t1
t2
ACsns_low
Vdd(on)