ISL6150IB Intersil, ISL6150IB Datasheet - Page 16

• Manufacturer Part Number: ISL6150IB
• Description: IC CTRLR HOT PLUG NEG VOLT 8SOIC
• Manufacturer: Intersil
• Type: Hot-Swap Controllerr

Specifications of ISL6150IB

• Applications: General Purpose, VoIP
• Internal Switch(s): No
• Voltage - Supply: 36 V ~ 72 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Inrush Current
In the example in Figure 26, the supply voltage is 48V
and the load resistor (RL) is 620Ω, for around 80mA.
The load capacitance is 100μF (100V). The Sense
Resistor (R
the inrush current here).
Note that the load current starts at 0 (FET off); reaches
a peak of ~850mA as the GATE voltage ramps and
turns on the FET slowly, and then settles out at 80mA,
once the CL is fully charged to the 48V. The width of
the inrush current pulse is 8ms wide. For comparison,
with the same conditions, but without the
gate-controlled FET, the current was over 20A, during a
130µs pulse.
Power Supply Ramp
Figure 27 shows the power supply voltage (to the V
pin, with respect to GND at the V
this case, the values chosen were R
R5 = 5.9k; R
around 38V, and the OV trip point to 54V. Note that the
GATE starts at 0V, and stays there until the UV trip
point (38V) is exceeded; then it ramps (slowly, based
on the external components chosen) up to around 13V,
where it is clamped; it stays there until the power
supply exceeds the OV trip point at 54V (the GATE
shut-off is much faster than the turn-on). The total
time scale is 2 seconds; the V
simply based on the inherent characteristic of the
particular power supply used.
Load
Current
CURRENT
LOAD
48V
48V
1
FIGURE 26. INRUSH CURRENT
) is 0.02Ω (trip point at 2.5A; well above
6
= 13.3k; that sets the UV trip point
PWRGD-bar
16
PWRGD-BAR
DD
EE
ramp speed was
pin) ramping up. In
GATE
4
GATE
= 562k;
ISL6140, ISL6150
DD
Overcurrent at 2.3A
In Figure 28, an Electronic Load Generator was used to
ramp the load current; no load resistor or capacitor
was connected. The sense Resistor R
should make the nominal overcurrent trip point 2.5A.
The GATE is high (clamped to around 13V), keeping
the FET on, as the current starts to ramp up from zero;
the GATE starts to go low (to shut off the FET) when
the load current hits 2.3A. Note that it takes only 44µs
for the GATE to shut off the FET (when the load current
equals zero).
Keep in mind that the tolerance of the sense resistor
(1% here) and the IC overcurrent trip voltage (V
affect the accuracy of the trip point; that’s why the trip
point doesn’t necessarily equal the 2.5A design target.
LOAD CURRENT
OFF
Load Current
FIGURE 28. OVERCURRENT AT 2.3A
GATE
OV = 54V
FIGURE 27. POWER SUPPLY RAMP
UV = 38V
ON
13V
GATE
OFF
V
GATE
DD
2.3 A
2.3A
1
is 0.02Ω; that
R1 = 0.02 oh
48V
No cap
R1 = 0.02Ω
48V
NO CAP
V
DD
FN9039.4
CB
= 60V
)
Ω