MAX5922AEUI MAXIM [Maxim Integrated Products], MAX5922AEUI Datasheet - Page 13

• Manufacturer Part Number: MAX5922AEUI
• Description: +48V, Single-Port Network Power Switch For Power-Over-LAN
• Manufacturer: MAXIM [Maxim Integrated Products]

Figure 2. Operational Flow Chart (MAX5922A and MAX5922B/MAX5922C with DET_DIS Connected Low)
*FOR THE MAX5922B, THE DCA FUNCTION IS INTERNALLY DISABLED. FOR THE MAX5922C, THE DCA FUNCTION IS INTERNALLY ENABLED.
INCREMENT
t
t
ZC_DEG
ZC_DEG
RESET
POWER-ON
N
+48V, Single-Port Network Power Switch
______________________________________________________________________________________
SWITCH SHUTOFF
LATCH = HIBH
FAULT = LOW
Y
t
ZCDEL
RESET t
INCREMENT
SHUT-OFF
ZC = LOW
Y
N
SWITCH
t
t
< I
ZCDEL
Is I
ZC_DEG
10ms?
= 350ms?
ZCTH
OUT
ZCDEL
Y
?
=
Y
RESET
N
Y
N
Y
V
OUT
LOW TO HIGH
Y
N
EN = LOW?
ELAPSED?
- V
POK HIGH
t
RESTART
t
POK_DLY
AFTER
OVERCURRENT
IN
< V
DETECTED
V
N
SHUTDOWN
DETECTED?
N
IN
Y
THERMAL
THPOK
> UVLO
t
RESET
ZC_DEG
t
ZCDEL
?
N
TH
Y
?
Y
N
AFTER t
HIGH TO LOW
POK LOW
POK_DLY
Y
EN = HIGH?
N
IS POK HIGH?
ZC_EN =
HIGH?
Y
Y
N
START POWER-UP
FAULT AND ZC
REPORT CLASS
N
RESET
STATUS
Y
For Power-Over-LAN
OVERCURRENT
COUNTER
RESET
N
N
Cl0 = CL1 = CL2 = HIGH
START PD DECTECTION
FORCE OUT = V
CL0 = CL1 = CL2 = HIGH
RESET COUNTERS
V
and MEASURE I
PD CLASSIFICATION
OUT
WAIT I/2t
CLASS = H?
WAIT t
= V
FORCE
START
CLASS
N
CLASS
DET
PBI
OVERCURRENT
Y
OVERCURRENT
(17.5V)
CLASS
INCREMENT
CONDITION?
COUNTER
(4V)
Y
Y
Note 1
FORCE OUT = V
I
DET
SAMPLE AND HOLD
OUTPUT IN HIGH-Z
WAIT 1/2t DET
(V
= I
IS DCA HIGH?
PBI
MEASURE
SENSE2
WAIT t
I
SENSE1
- V
OK?
IS
PBI
DCA
- I
PBI
N
)/I
OVERCURRENT
COUNTER = 60?
SENSE1
DET
(8V)
Y
N
N
Y
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