HCPL3150 HP [Agilent(Hewlett-Packard)], HCPL3150 Datasheet - Page 14

• Manufacturer Part Number: HCPL3150
• Description: 0.5 Amp Output Current IGBT Gate Drive Optocoupler
• Manufacturer: HP [Agilent(Hewlett-Packard)]

+5 V
+5 V
Figure 29. Optocoupler Input to Output
Capacitance Model for Unshielded Optocouplers.
Figure 33. Recommended LED Drive
Circuit for Ultra-High CMR.
Figure 31. Equivalent Circuit for Figure 25 During
Common Mode Transient.
1-210
1
2
3
4
C
C
LEDP
LEDN
V
+
–
SAT
1
2
3
4
C
C
LEDP
LEDN
* THE ARROWS INDICATE THE DIRECTION
OF CURRENT FLOW DURING –dV
1
2
3
4
SHIELD
C
C
I
LEDP
LEDP
LEDN
SHIELD
8
7
6
5
V
+
CM
–
8
7
6
5
CM
turn off of LED1) so that under
worst-case conditions, transistor
Q1 has just turned off when
transistor Q2 turns on, as shown
in Figure 34. The amount of delay
necessary to achieve this condi-
tions is equal to the maximum
value of the propagation delay
difference specification, PDD
which is specified to be 350 ns
over the operating temperature
range of -40 C to 100 C.
Delaying the LED signal by the
maximum propagation delay
difference ensures that the
minimum dead time is zero, but it
does not tell a designer what the
maximum dead time will be. The
/dt.
8
7
6
5
0.1
µF
+
–
Rg
V
CC
Figure 30. Optocoupler Input to Output
Capacitance Model for Shielded Optocouplers.
1
2
3
4
= 18 V
• • •
• • •
C
C
LEDP
LEDN
SHIELD
C
LEDO1
MAX
C
,
LEDO2
+5 V
Figure 32. Not Recommended Open
Collector Drive Circuit.
Q1
maximum dead time is equivalent
to the difference between the
maximum and minimum propaga-
tion delay difference specifica-
tions as shown in Figure 35. The
maximum dead time for the
HCPL-3150 is 700 ns (= 350 ns -
(-350 ns)) over an operating
temperature range of -40 C to
100 C.
Note that the propagation delays
used to calculate PDD and dead
time are taken at equal tempera-
tures and test conditions since
the optocouplers under consider-
ation are typically mounted in
close proximity to each other and
are switching identical IGBTs.
8
7
6
5
1
2
3
4
C
C
I
LEDN
LEDN
LEDP
SHIELD
8
7
6
5