Datasheet

MAX5955/MAX5956
Low-Voltage, Dual Hot-Swap Controllers with
Independent On/Off Control
_______________________________________________________________________________________ 5
0.1
1
10
20 30 3525
40
45 50 55 60 65 70 75 80
TURN-OFF TIME vs. SENSE VOLTAGE
(EXPANDED SCALE)
MAX5955/56 toc10
V
IN
- V
SENSE
(mV)
TURN-OFF TIME (ms)
SLOW-COMP. THRESHOLD
0
40
20
80
60
100
120
0 200100 300 400
SLOW-COMPARATOR THRESHOLD
vs. R
LIM
MAX5955/56 toc11
R
LIM
(k
Ω
)
V
SC,TH
(mV)
0
20
10
40
30
50
60
STARTUP PERIOD vs. R
TIM
MAX5955/56 toc12
R
TIM
(k
Ω
)
t
START
(ms)
0 200 300100 400 500 600
0
0
0
V
PGOOD
5V/div
V
SENSE
- V
IN
100mV/div
V
GATE
5V/div
TURN-OFF TIME
SLOW-COMPARATOR FAULT
MAX5955/56 toc13
1ms/div
V
IN
= 5.0V
t
SCD
26mV STEP
0
0
0
V
PGOOD
5V/div
V
SENSE
- V
IN
100mV/div
V
GATE
5V/div
TURN-OFF TIME
FAST-COMPARATOR FAULT
MAX5955/56 toc14
400ns/div
V
IN
= 5.0V
t
FCD
125mV STEP
V
ON
2V/div
V
PGOOD
2V/div
I
OUT
5A/div
V
OUT
5V/div
V
GATE
5V/div
STARTUP WAVEFORMS
FAST TURN-ON
MAX5955/56 toc15
1ms/div
V
IN
= 5.0V, R
SENSE
= 10m
Ω
,
R
TIM
= 27k
Ω
, C
BOARD
= 1000
µ
F
V
ON
2V/div
V
PGOOD
2V/div
I
OUT
5A/div
V
OUT
5V/div
V
GATE
5V/div
STARTUP
WAVEFORMS
SLOW TURN-ON
MAX5955/56 toc16
1ms/div
V
IN
= 5.0V, R
SENSE
= 10mΩ, R
TIM
= 47kΩ,
C
BOARD
= 1000µF, C
GATE
= 22nF
I
OUT
5A/div
V
OUT
5V/div
V
GATE
5V/div
AUTORETRY DELAY
MAX5955/56 toc17
40ms/div
V
IN
= 5.0V, R
SENSE
= 10mΩ, R
TIM
= 47kΩ,
C
BOARD
= 1000µF, R
BOARD
= 1.4Ω
Typical Operating Characteristics (continued)
(Typical Operating Circuits, Q1 = Q2 = Fairchild FDB7090L, V
IN1
= +5V, V
IN2
= +3.3V, V
ON1
= V
ON2
= +2.7V, T
A
= +25°C, unless
otherwise noted. Channels 1 and 2 are identical in performance. Where characteristics are interchangeable, channels 1 and 2 are
referred to as X and Y.)