hip6005b Intersil Corporation, hip6005b Datasheet - Page 10

• Manufacturer Part Number: hip6005b
• Description: Buck Pulse-width Modulator Pwm Controller And Output Voltage Monitor
• Manufacturer: Intersil Corporation

NOTE: V
FIGURE 10. UPPER GATE DRIVE - DIRECT V
FIGURE 9. UPPER GATE DRIVE - BOOTSTRAP OPTION
HIP6005B
+
-
+12V
G-S
HIP6005B
+
-
+12V
VCC
V
VCC
CC
- V
GND
D
BOOT
UGATE
PHASE
.
+ V
GND
D
BOOT
2-119
D
BOOT
UGATE
PHASE
-
C
BOOT
Q
+5V OR LESS
1
D
2
(NOTE)
+5V OR +12
Q
D
1
CC
2
NOTE:
V
G-S
DRIVE OPTION
V
CC
-5V
HIP6005B
Schottky Selection
Rectifier D
diode should be a Schottky type for low power losses. The
power dissipation in the Schottky rectifier is approximated by:
In addition to power dissipation, package selection and
heat-sink requirements are the main design tradeoffs in
choosing the schottky rectifier. Since the three factors are
interrelated, the selection process is an iterative procedure.
The maximum junction temperature of the rectifier must
remain below the manufacturer’s specified value, typically
125
and the schottky power dissipation equation (shown above),
the junction temperature of the rectifier can be estimated. Be
sure to use the available airflow and ambient temperature to
determine the junction temperature rise.
Where: D is the duty cycle = V
P
COND
o
C. By using the package thermal resistance specification
V
= I
f
2
0
conducts when the upper MOSFET Q
is the Schottky forward voltage drop.
x V
f
x (1 - D)
OUT
/ V
IN
, and
1
is off. The