hip6018cb Intersil Corporation, hip6018cb Datasheet - Page 9

• Manufacturer Part Number: hip6018cb
• Description: Advanced Pwm And Dual Linear Power Control
• Manufacturer: Intersil Corporation

MOSFET switching. The over-current function will trip at a peak
inductor current (I
The OC trip point varies with MOSFET’s temperature. To avoid
over-current tripping in the normal operating load range,
determine the R
For an equation for the output inductor ripple current see
the section under component guidelines titled ‘Output
Inductor Selection’.
OUT1 Voltage Program
The output voltage of the PWM converter is programmed to
discrete levels between 1.8V
designed to supply the microprocessor core voltage. The
voltage identification (VID) pins program an internal voltage
reference (DACOUT) through a TTL-compatible 5-bit
digital-to-analog converter. The level of DACOUT also sets
the PGOOD and OVP thresholds. Table 1 specifies the
DACOUT voltage for the different combinations of
connections on the VID pins. The VID pins can be left open
for a logic 1 input, because they are internally pulled up to
+5V by a 10µA (typically) current source. Changing the VID
inputs during operation is not recommended. The sudden
change in the resulting reference voltage could toggle the
PGOOD signal and exercise the over-voltage protection. All
VID pin combinations resulting in an INHIBIT disable the IC
and the open-collector at the PGOOD pin.
I
PEAK
1. The maximum r
2. The minimum I
3. Determine I
CURRENT1
OC1
HIP6018
OVER-CURRENT TRIP: V
OVER-
temperature.
where ∆I is the output inductor ripple current.
(i
D
PWM
=
• r
DS
I
---------------------------------------------------- -
OC SET
+
-
FIGURE 9. OVER-CURRENT DETECTION
(ON) > I
CONTROL
r
DS ON
GATE
PEAK
OCSET
x R
PEAK)
(
OCSET
OCSET
DS(ON)
OCSET
DRIVE
)
for I
I
OCSET
200µA
resistor from the equation above with:
• R
determined by:
DS
PEAK
OCSET
from the specification table.
at the highest junction
> V
232
DC
SET
VCC
VCC
> I
)
OCSET
PHASE
UGATE
LGATE
and 3.5V
PGND
OUT(MAX)
DC
V
V
R
V
OCSET
PHASE
OCSET
+ (∆I)/2,
SET
. This output is
+
= V
= V
V
IN
IN
IN
I
D
+
- V
V
- V
= +5V
DS
SET
DS
HIP6018
NOTE: 0 = connected to GND or V
through pull-up resistors, X = don’t care
Application Guidelines
Soft-Start Interval
Initially, the soft-start function clamps the error amplifier’s
output of the PWM converter. After the output voltage
increases to approximately 80% of the set value, the
reference input of the error amplifier is clamped to a voltage
proportional to the SS pin voltage. Both linear outputs follow
a similar start-up sequence. The resulting output voltage
sequence is shown in Figure 6.
VID4
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
TABLE 1. V
VID3
1
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
PIN NAME
VID2
OUT1
X
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
VOLTAGE PROGRAM
SS
VID1
X
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
, 1 = open or connected to 5V
VID0
X
X
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
VOLTAGE
NOMINAL
DACOUT
INHIBIT
INHIBIT
INHIBIT
OUT1
1.80
1.85
1.90
1.95
2.00
2.05
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5