Electrical characteristics (continued) – Rainbow Electronics MAX5971А User Manual
Page 5
_______________________________________________________________________________________ 5
MAX5971A
Single-Port, 40W, IEEE 802.3af/802.3at PSE
Controller with Integrated MOSFET
Note 2: All devices are production tested at T
A
= +25NC. Limits at T
A
= -40NC and +85NC are guaranteed by design.
Note 3: If ILIM1 and ILIM2 are both unconnected, Class 5 detection is disabled. See the Class 5 PD Classification section and Table 3 for
details and settings.
Note 4: R
DOK
= (V
OUT2
- V
OUT1
)/(I
DET2
- I
DET1
). V
OUT1
, V
OUT2
, I
DET2
, and I
DET1
represent the voltage at OUT and the current at
DET during phase 1 and 2 of the detection, respectively.
Note 5: If Class 5 is enabled, this is the classification current thresholds from Class 4 to Class 5.
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
DIGITAL INPUTS/OUTPUTS (Voltages referenced to V
EE
)
Digital Input Low
V
IL
0.8
V
Digital Input High
V
IH
2.4
V
Internal Input Pullup Current
I
PU
Pullup current to internal digital supply to
set default values
3
5
7
F
A
LED Output Low Voltage
V
LED_LOW
I
LED
= 10mA, PWM disabled, port power-on
0.8
V
LED Output Leakage
I
LED_LEAK
PWM disabled, shutdown mode,
V
LED
= 60V
10
F
A
PWM Frequency
25
kHz
PWM Duty Cycle
6.25
%
TIMING
Startup Time
t
START
Time during which a current limit set to
420mA is allowed, starts when power is
turned on
50
60
70
ms
Fault Time
t
FAULT
Maximum allowed time for an overcurrent
condition set by I
CUT
after startup
50
60
70
ms
Detection Reset Time
t
ME
Time allowed for the port voltage to reset
before detection starts
80
90
ms
Detection Time
t
DET
Maximum time allowed before detection is
completed
330
ms
Midspan Mode Detection Delay
t
DMID
2
2.2
2.4
s
Classification Time
t
CLASS
Time allowed for classification
19
23
ms
Mark Event Time
Time allowed for mark event
7
9
11
ms
V
EEUVLO
Turn-On Delay
t
DLY
Time V
AGND
must be above the V
EEUVLO
thresholds before the device operates
5.2
ms
Restart Timer
t
RESTART
Time the device waits before turning on
after an overcurrent fault
16 x
t
FAULT
ms