max5952auaxt Maxim Integrated Products, Inc., max5952auaxt Datasheet - Page 33

• Manufacturer Part Number: max5952auaxt
• Description: Max5952 High-power, Quad, Pse Controller For Power-over-ethernet
• Manufacturer: Maxim Integrated Products, Inc.

Setting DET_EN_/CLASS_EN_ to 1 (Table 18) enables
load detection/classification, respectively. Detection
always has priority over classification. To perform clas-
sification without detection, set the DET_EN_ bit low
and CLASS_EN_ bit high.
In manual mode, R14h works like a pushbutton. Set the
bits high to begin the corresponding routine. The bit
clears after the routine finishes.
CL_DISC (R17h[2]) and ENx_CL6 (R1Ch[7:4]) are used
to program the high-power mode. See Table 3 for details.
Setting BCKOFF_ to 1 (Table 19) enables cadence tim-
ing on each port where the port backs off and waits
2.2s after each failed load discovery detection. The
Table 18. Detection and Classification Enable Register
Table 19. Backoff and High-Power Enable Register
CLASS_EN4
CLASS_EN3
CLASS_EN4
CLASS_EN3
DET_EN4
DET_EN3
DET_EN2
DET_EN1
BCKOFF4
BCKOFF3
BCKOFF2
BCKOFF1
SYMBOL
SYMBOL
ADDRESS = 14h
ADDRESS = 15h
______________________________________________________________________________________
BIT
BIT
7
6
5
4
3
2
1
0
3
2
1
0
High-Power, Quad, PSE Controller
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Enable classification on port 4
Enable classification on port 3
Enable classification on port 2
Enable classification on port 1
Enable detection on port 4
Enable detection on port 3
Enable detection on port 2
Enable detection on port 1
Enable cadence timing on port 4
Enable cadence timing on port 3
Enable cadence timing on port 2
Enable cadence timing on port 1
for Power-Over-Ethernet
When entering auto mode, R14h defaults to FFh. When
entering semi or manual modes, R14h defaults to 00h.
A reset or power-up sets R14h = AAAAAAAAb where A
represents the latched-in state of the AUTO input prior
to the reset.
IEEE 802.3af standard requires a PSE that delivers
power through the spare pairs (midspan PSE) to have
cadence timing.
A reset or power-up sets R15h = 0000XXXXb where ‘X’
is the logic AND of the MIDSPAN and AUTO inputs.
DESCRIPTION
DESCRIPTION
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