Diodes ZXGD3005E6 - Manual (Page 6)

ZXGD3005E6
Document Number DS35095 Rev. 4 – 2
6 of 8
www.diodes.com
March 2011
© Diodes Incorporated
A Product Line of
Diodes Incorporated
ZXGD3005E6
ADVAN
CE I
N
F
O
RM
ATI
O
N Application Notes
Independent control of rise and fall time
An application may require the turn-on (t
on
) and turn-off (t
off
) time
to be independently controlled, which can be achieved by setting
different R
SOURCE
and R
SINK
values. With asymmetric R
SOURCE
and R
SINK
resistors, then a potential difference will occur between
the SOURCE and SINK pins during the switching transition. If the
potential difference across the SOURCE and SINK pins is greater
than 7.5V, then it could damage the ZXGD3005.
In this circuit example of driving an IGBT, a blocking diode is
added in series with R
SINK
to protect against excess reverse
current being induced into the SINK pin.
Circuit example of driving a MOSFET
Application example of gate driving a MOSFET from 0 to 15V with
R
SOURCE
= R
SINK
= 0 Ω
Switching Time Characteristic
0 100 200 300 400 500 600 700 800
0
5
10
15
Symmetric Source and Sink Resistors
V
IN
= 0 to 15V
V
CC
= 15V
V
EE
= 0V
R
IN
= 1k Ω
C
L
= 10nF
R
L
= 0.18 Ω
R
SOURCE
= 0 Ω
R
SINK
= 0 Ω
V
OUT
V
o
lt
age (
V
)
Time (ns)
V
IN
Circuit example of driving an IGBT
Application example of gate driving an IGBT with independent t
on
and
t
off
using asymmetric R
SOURCE
and R
SINK
In addition, the gate is
driven from -5 to +15V to prevent dV/dt induced false triggering.
Switching Time Characteristic
0 100 200 300 400 500 600 700 800
-5
0
5
10
15 V
IN
= -5 to 15V
V
CC
= 15V
V
EE
= -5V
R
IN
= 1k Ω
C
L
= 10nF
R
L
= 0.18 Ω
R
SOURCE
= 4.7 Ω
R
SINK
= 0 Ω
Asymmetric Source and Sink Resistors
V
IN
V
OUT
V
o
lt
ag
e (V
)
Time (ns)