l6393 STMicroelectronics, l6393 Datasheet - Page 15

• Manufacturer Part Number: l6393
• Description: Half-bridge Gate Driver
• Manufacturer: STMicroelectronics

L6393
where Q
bootstrap DMOS, and T
For example: using a power MOS with a total gate charge of 30 nC the drop on the
bootstrap DMOS is about 1 V, if the T
V
is too high, or the circuit topology doesn’t allow a sufficient charging time, an external diode
can be used.
Figure 6.
drop
V
S
has to be taken into account when the voltage drop on C
gate
D
BOOT
is the gate charge of the external power MOS, R
Bootstrap driver
a
HVG
LVG
charge
V
BOOT
V
OUT
is the charging time of the bootstrap capacitor.
drop
H.V.
=
charge
30nC
-------------- - 120Ω 0.7V
C
TO LOAD
BOOT
5µs
is 5 µs. In fact:
⋅
V
S
∼
DSon
BOOT
b
HVG
LVG
is the on resistance of the
is calculated: if this drop
Bootstrap driver
BOOT
V
OUT
H.V.
D99IN1067
C
TO LOAD
BOOT
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