Rainbow Electronics MAX5971B - Manual (Page 4)

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MAX5971B
Single-Port, 40W, IEEE 802.3af/at,
PSE Controller with I 2 C
ELECTRICAL CHARACTERISTICS (continued)
(V AGND - V EE = 32V to 60V, T A = -40NC to +85NC, all voltages are referenced to V EE , unless otherwise noted. Typical values are at
V AGND - V EE = +54V, T A = +25NC. Currents are positive when entering the pin and negative otherwise.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
LOAD DISCONNECT
DC Load-Disconnect Threshold I DCTH
Minimum load current allowed before
disconnect (DC disconnect active),
V
OUT = 0V
5 7.5 10 mA
AC Load-Disconnect Threshold
(Note 4)
I ACTH
Current into DET, for I
DET
< I
ACTH
the port
powers off (AC disconnect active)
115 130 145 F A
Triangular Wave Peak-to-Peak
Voltage Amplitude
AMP
TRW
Measured at DET, referred to AGND 3.85 4 4.2 V
OSC Pullup/Pulldown Currents I OSC Measured at OSC 26 32 39 F A
ACD_EN Threshold V ACD_EN
V OSC - V EE > V ACD_EN to activate AC
disconnect
270 330 380 mV
Load-Disconnect Timer t DISC
Time from I RSENSE < I DCTH (DC
disconnect active) or I DET < I ACTH (AC
disconnect active) to gate shutdown
(Note 5)
300 400 ms
DETECTION
Detection Probe Voltage
(First Phase)
V DPH1
V AGND - V DET during the first detection
phase
3.8 4 4.2 V
Detection Probe Voltage
(Second Phase)
V DPH2
V AGND - V DET during the second detection
phase
9 9.3 9.6 V
Current-Limit Protection I DLIM
V DET = V AGND during detection, measure
current through DET
1.50 1.75 2.00 mA
Short-Circuit Threshold V DCP
If V AGND - V OUT < V DCP after the first
detection phase a short circuit to AGND is
detected. 1 V
Open-Circuit Threshold I D_OPEN
First point measurement current threshold
for open condition
20 F A
Resistor Detection Window R DOK (Note 6) 19 26.5 kI
Resistor Rejection Window R DBAD
Detection rejects lower values 15.5
kI
Detection rejects higher values 32
CLASSIFICATION
Classification Probe Voltage
V CL V AGND - V DET during classification 16 20 V
Current-Limit Protection I ClLIM
V DET = V AGND , during classification
measure current through DET
65 80 mA