HIP6004EVAL3 Intersil, HIP6004EVAL3 Datasheet - Page 5

• Manufacturer Part Number: HIP6004EVAL3
• Description: EVALUATION BOARD EMBED HIP6004
• Manufacturer: Intersil

Specifications of HIP6004EVAL3

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 1.3 ~ 3.5V
• Current - Output: 14A
• Voltage - Input: 5 ~ 12V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: HIP6004
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power - Output: -
• Frequency - Switching: -

PGND (Pin 16)
This is the power ground connection. Tie the lower MOSFET
source to this pin.
LGATE (Pin 17)
Connect LGATE to the lower MOSFET gate. This pin
provides the gate drive for the lower MOSFET.
VCC (Pin 18)
Provide a 12V bias supply for the chip to this pin.
OVP (Pin 19)
The OVP pin can be used to drive an external SCR in the
event of an overvoltage condition.
RT (Pin 20)
This pin provides oscillator switching frequency adjustment.
By placing a resistor (R
200kHz switching frequency is increased according to the
following equation:
Conversely, connecting a pull-up resistor (R
to VCC reduces the switching frequency according to the
following equation:
Functional Description
Initialization
The HIP6004 automatically initializes upon receipt of power.
Special sequencing of the input supplies is not necessary.
The Power-On Reset (POR) function continually monitors
the input supply voltages. The POR monitors the bias
voltage at the VCC pin and the input voltage (V
OCSET pin. The level on OCSET is equal to V
voltage drop (see over-current protection). The POR
function initiates soft start operation after both input supply
voltages exceed their POR thresholds. For operation with a
single +12V power source, V
the +12V power source must exceed the rising V
threshold before POR initiates operation.
Soft Start
The POR function initiates the soft start sequence. An internal
10μA current source charges an external capacitor (C
the SS pin to 4V. Soft start clamps the error amplifier output
(COMP pin) and reference input (+ terminal of error amp) to the
SS pin voltage. Figure 3 shows the soft start interval with
C
pin) controls the converter’s output voltage. At t
the SS voltage reaches the valley of the oscillator’s triangle
wave. The oscillator’s triangular waveform is compared to the
ramping error amplifier voltage. This generates PHASE pulses
Fs
Fs
SS
≈
≈
200kHz
200kHz
= 0.1μF. Initially the clamp on the error amplifier (COMP
+
–
-------------------- -
R
-------------------- -
R
4 10
5 10
T
T
•
•
(
(
kΩ
kΩ
6
7
)
)
T
) from this pin to GND, the nominal
(R
(R
T
T
IN
to 12V)
to GND)
5
and V
CC
are equivalent and
T
1
) from this pin
IN
in Figure 3,
IN
less a fixed
CC
) on the
SS
) on
HIP6004
of increasing width that charge the output capacitor(s). This
interval of increasing pulse width continues to t
output voltage, the clamp on the reference input controls the
output voltage. This is the interval between t
At t
output voltage is in regulation. This method provides a rapid
and controlled output voltage rise. The PGOOD signal toggles
‘high’ when the output voltage (VSEN pin) is within ±5% of
DACOUT. The 2% hysteresis built into the power good
comparators prevents PGOOD oscillation due to nominal
output voltage ripple.
Over-Current Protection
The over-current function protects the converter from a
shorted output by using the upper MOSFETs on-resistance,
r
converter’s efficiency and reduces cost by eliminating a
current sensing resistor.
The over-current function cycles the soft-start function in a
hiccup mode to provide fault protection. A resistor (R
programs the over-current trip level. An internal 200μA current
sink develops a voltage across R
V
DS(ON)
0V
0V
0V
IN
3
. When the voltage across the upper MOSFET (also
15A
10A
the SS voltage exceeds the DACOUT voltage and the
5A
0A
4V
2V
0V
to monitor the current. This method enhances the
FIGURE 4. OVER-CURRENT OPERATION
SOFT-START
(1V/DIV.)
FIGURE 3. SOFT START INTERVAL
t
1
TIME (5ms/DIV.)
PGOOD
(2V/DIV.)
TIME (20ms/DIV.)
t
2
OCSET
that is referenced to
t
3
2
and t
2
. With sufficient
OUTPUT
VOLTAGE
(1V/DIV.)
3
in Figure 3.
OCSET
)