HIP6014 Intersil Corporation, HIP6014 Datasheet - Page 10

• Manufacturer Part Number: HIP6014
• Description: Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor
• Manufacturer: Intersil Corporation

Standard-gate MOSFETs are normally recommended for
use with the HIP6014. However, logic-level gate MOSFETs
can be used under special circumstances. The input voltage,
upper gate drive level, and the MOSFET’s absolute gate-to-
source voltage rating determine whether logic-level
MOSFETs are appropriate.
Figure 9 shows the upper gate drive (BOOT pin) supplied by
a bootstrap circuit from V
develops a floating supply voltage referenced to the PHASE
pin. This supply is refreshed each cycle to a voltage of V
less the boot diode drop (V
turns on. Logic-level MOSFETs can only be used if the
MOSFET’s absolute gate-to-source voltage rating exceeds
the maximum voltage applied to V
HIP6014
+
-
FIGURE 9. UPPER GATE DRIVE - BOOTSTRAP OPTION
V
+12V
CC
+ V
GND
D
BOOT
BOOT
UGATE
PHASE
LGATE
PGND
D
-
CC
D
C
. The boot capacitor, C
) when the lower MOSFET, Q
BOOT
10
CC
Q1
Q2
FIGURE 10. UPPER GATE DRIVE - DIRECT V
+5V or +12V
.
HIP6014
-
+
+12V
D2
NOTE:
V
NOTE:
V
G-S
G-S
V
CC
V
BOOT
V
CC
GND
CC
BOOT
UGATE
PHASE
LGATE
PGND
-V
CC
D
2
HIP6014
Figure 10 shows the upper gate drive supplied by a direct
connection to V
converter systems where the main input voltage is +5V
less. The peak upper gate-to-source voltage is approximately
V
for the bias, the gate-to-source voltage of Q
level MOSFET is a good choice for Q
MOSFET can be used for Q
voltage rating exceeds the maximum voltage applied to V
Schottky Selection
Rectifier D
swing during the dead time between turning off the lower
MOSFET and turning on the upper MOSFET. The diode
must be a Schottky type to prevent the lossy parasitic
MOSFET body diode from conducting. It is acceptable to
omit the diode and let the body diode of the lower MOSFET
clamp the negative inductor swing, but efficiency will drop
one or two percent as a result. The diode's rated reverse
breakdown voltage must be greater than the maximum input
voltage.
Q
Q
+5V OR LESS
CC
1
2
less the input supply. For +5V main power and +12V
D
CC
2
NOTE:
V
2
NOTE:
V
G-S
DRIVE OPTION
G-S
is a clamp that catches the negative inductor
CC
V
V
CC
CC
. This option should only be used in
-5V
2
if its absolute gate-to-source
1
and a logic-level
1
is 7V. A logic-
DC
CC.
DC
or