HIP6015 View Datasheet(PDF) - Intersil
Part Name
Description
MFG CO.
HIP6015 Datasheet PDF : 12 Pages
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HIP6015
Over-Current Protection
The over-current function protects the converter from a
shorted output by using the upper MOSFET’s on-resistance,
rDS(ON) to monitor the current. This method enhances the
converter’s efficiency and reduces cost by eliminating a
current sensing resistor.
4V
2V
0V
15A
10A
inhibits PWM operation. The soft-start function recharges
CSS, and PWM operation resumes with the error amplifier
clamped to the SS voltage. Should an overload occur while
recharging CSS, the soft start function inhibits PWM operation
while fully charging CSS to 4V to complete its cycle. Figure 4
shows this operation with an overload condition. Note that the
inductor current increases to over 15A during the CSS
charging interval and causes an over-current trip. The
converter dissipates very little power with this method. The
measured input power for the conditions of Figure 4 is 2.5W.
The over-current function will trip at a peak inductor current
(IPEAK) determined by:
IPEAK = I--O-----C----S----rE--D--T--S---•-(--O-R----NO----)-C----S----E----T--
5A
where IOCSET is the internal OCSET current source (200µA
typical). The OC trip point varies mainly due to the
0A
TIME (20ms/DIV.)
MOSFET’s rDS(ON) variations. To avoid over-current tripping
in the normal operating load range, find the ROCSET resistor
from the equation above with:
FIGURE 4. OVER-CURRENT OPERATION
1. The maximum rDS(ON) at the highest junction temperature.
2. The minimum IOCSET from the specification table.
The over-current function cycles the soft-start function in a
hiccup mode to provide fault protection. A resistor (ROCSET)
programs the over-current trip level. An internal 200µA current
3. Determine IPEAK for IPEAK > IOUT(MAX) + (∆I) ⁄ 2 ,
where ∆I is the output inductor ripple current.
For an equation for the ripple current see the section under
sink develops a voltage across ROCSET that is referenced to
component guidelines titled “Output Inductor Selection.”
VIN. When the voltage across the upper MOSFET (also
referenced to VIN) exceeds the voltage across ROCSET, the
over-current function initiates a soft-start sequence. The soft-
start function discharges CSS with a 10µA current sink and
A small ceramic capacitor should be placed in parallel with
ROCSET to smooth the voltage across ROCSET in the
presence of switching noise on the input voltage.
TABLE 1. OUTPUT VOLTAGE PROGRAM
VID4
PIN NAME
VID3 VID2 VID1
VID0
NOMINAL OUTPUT
VOLTAGE DACOUT
VID4
PIN NAME
VID3 VID2 VID1
VID0
NOMINAL OUTPUT
VOLTAGE DACOUT
0
1
1
1
1
0
1
1
1
1
1
0
0
1
1
1
0
0
1
1
1
1
0
2.1
0
1
1
0
1
0
1
1
1
0
1
2.2
0
1
1
0
0
0
1
1
1
0
0
2.3
0
1
0
1
1
0
1
1
0
1
1
2.4
0
1
0
1
0
0
1
1
0
1
0
2.5
0
1
0
0
1
0
1
1
0
0
1
2.6
0
1
0
0
0
0
1
1
0
0
0
2.7
0
0
1
1
1
0
1
0
1
1
1
2.8
0
0
1
1
0
0
1
0
1
1
0
2.9
0
0
1
0
1
1.80
1
0
1
0
1
3.0
0
0
1
0
0
1.85
1
0
1
0
0
3.1
0
0
0
1
1
1.90
1
0
0
1
1
3.2
0
0
0
1
0
1.95
1
0
0
1
0
3.3
0
0
0
0
1
2.00
1
0
0
0
1
3.4
0
0
0
0
0
2.05
1
0
0
0
0
3.5
NOTE: 0 = connected to GND or VSS, 1 = connected to VDD through pull-up resistors.
6
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