Datasheet

MAX5942A/MAX5942B
IEEE 802.3af Power-Over-Ethernet
Interface/PWM Controller for Power Devices
_______________________________________________________________________________________ 3
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
UVLO Bias Current I
UVLO
UVLO = 2.460V
-1.5 +1.5
µA
UVLO Input Ground Sense
Threshold
V
TH
,
G
,
UVLO
(Note 8) 50 440 mV
UVLO Input Ground Sense Glitch
Rejection
UVLO = V
EE
7µs
Power Turn-Off Voltage,
Undervoltage Lockout Deglitch
Time
t
OFF_DLY
V
IN
, V
UVLO
falling (Note 9)
0.32
ms
T
A
= +25°C
(Note 11)
0.6
1.1
Isolation Switch N-Channel
MOSFET On-Resistance
R
ON
Output current =
300mA, V
GATE
= 5.6V,
measured between
OUT and V
EE
T
A
= +85°C
0.8
1.5
Ω
Isolation Switch N-Channel
MOSFET Off-Threshold Voltage
V
GSTH
OUT = GND, V
GATE
- V
EE,
output current
< 1µA
0.5 V
GATE Pulldown Switch Resistance
R
G
Power-off mode, V
IN
= 12V, UVLO = V
EE
38 80 Ω
GATE Charging Current I
G
V
GATE
= 2V 5 10 15 µA
GATE High Voltage V
GATE
I
GATE
= 1µA
5.58 5.76 5.93
V
V
OUT
- V
EE
, |V
OUT
- V
EE
| decreasing,
V
GATE
= 5.75V
1.15 1.23 1.31
V
PGOOD, PGOOD Assertion
V
OUT
Threshold
V
OUTEN
Hysteresis 70 mV
(GATE - V
EE
) increasing, OUT = V
EE
4.62 4.76 4.91
V
PGOOD, PGOOD Assertion
V
GATE
Threshold
V
GSEN
Hysteresis 80 mV
PGOOD Output Low Voltage
V
OLDCDC
I
SINK
= 2mA (Note 10) 0.4 V
PGOOD Output Low Voltage I
SINK
= 2mA, OUT ≤ (GND - 5V) (Note 10) 0.2 V
PGOOD Leakag e C ur r ent GATE = hi g h, GN D - V
OU T
= 67V ( N ote 10) 1 µA
PGOOD Leakag e C ur r ent GATE = V
E E
, P GOOD - V
E E
= 67V ( N ote 10) 1 µA
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= (GND - V
EE
) = 48V, GATE = PGOOD = PGOOD = OPEN, V- tied to OUT, V+ tied to GND, UVLO = V
EE
, T
A
= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C. All voltages are referenced to V
EE
, unless otherwise noted.) (Note 1)
ELECTRICAL CHARACTERISTICS (PWM Controller)
(All voltages referenced to V-. V
DD
= 13V, a 10µF capacitor connects V
CC
to V-, V
CS
= V-, V+ = 48V, 0.1µF capacitor connected to
SS_SHDN, NDRV = open circuit, V
FB
= 3V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SUPPLY CURRENT
I
V+(NS)
V
DD
= 0V, V+ = 67V, driver not switching 0.8 1.6
V+ Supply Current
I
V+(S)
V+ = 67V, V
DD
= 0V, V
FB
= 4V, driver
switching
1.6 3.2
mA
V+ Supply Current After Startup V+ = 67V, V
DD
= 13V, V
FB
= 4V 14 µA