ACPL-312U-300E Avago Technologies US Inc., ACPL-312U-300E Datasheet - Page 13

• Manufacturer Part Number: ACPL-312U-300E
• Description: OPTOCOUPLER IGBT 2.5A 8-SMD GW
• Manufacturer: Avago Technologies US Inc.
• Series: R²Coupler™r

Specifications of ACPL-312U-300E

• Voltage - Isolation: 3750Vrms
• Number Of Channels: 1, Unidirectional
• Current - Output / Channel: 2.5A
• Propagation Delay High - Low @ If: 300ns @ 7mA ~ 16mA
• Current - Dc Forward (if): 20mA
• Input Type: DC
• Output Type: Push-Pull, Totem-Pole
• Mounting Type: Surface Mount
• Package / Case: 8-SMD Gull Wing
• No. Of Channels: 1
• Optocoupler Output Type: Gate Drive
• Input Current: 16mA
• Output Voltage: 30V
• Opto Case Style: SMD
• No. Of Pins: 8
• Output Current: 500mA
• Output Voltage Max: 27V
• Isolation Voltage: 3.75kV
• Forward Current If: 20mA
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Applications Information
Eliminating Negative IGBT Gate Drive ACPL-312U
To keep the IGBT firmly off, the ACPL-312U has a very
low maximum V
realizes this very low V
with 1 : (typical) on resistance in its pull down circuit.
When the ACPL-312U is in the low state, the IGBT gate is
shorted to the emitter by Rg + 1 :. Minimizing Rg and
the lead inductance from the ACPL-312U to the IGBT gate
and emitter (possibly by mounting the ACPL-312U on a
small PC board directly above the IGBT) can eliminate the
need for negative IGBT gate drive in many applications
as shown in Figure 25. Care should be taken with such
a PC board design to avoid routing the IGBT collector or
emitter traces close to the ACPL-312U input as this can
result in unwanted coupling of transient signals into the
ACPL-312U and degrade performance. (If the IGBT drain
must be routed near the ACPL-312U input, then the LED
should be reverse-biased when in the off state, to prevent
the transient signals coupled from the IGBT drain from
turning on the ACPL-312U).
Figure 25. Recommended LED drive and application circuit.
Figure 26. ACPL-312U typical application circuit with negative IGBT gate drive.
13
CONTROL
CONTROL
CMOS
DRIVER
CMOS
DRIVER
INPUT
INPUT
+5 V
+5 V
270 :
270 :
OL
specification of 0.5 V. The ACPL-312U
OL
1
2
3
4
1
2
3
4
by using a DMOS transistor
ACPL-312U
8
7
6
5
0.1 μF
8
7
6
5
0.1 μF
+
–
+
–
Selecting the Gate Resistor (Rg) to Minimize IGBT Switching
Losses.
Step 1: Calculate Rg Minimum from the I
cation. The IGBT and Rg in Figure 26 can be analyzed as
a simple RC circuit with a voltage supplied by the ACPL-
312U.
The V
vative value of VOL at the peak current of 2.5A (see Figure
6). At lower Rg values the voltage supplied by the ACPL-
312U is not an ideal voltage step. This results in lower peak
currents (more margin) than predicted by this analysis.
When negative gate drive is not used VEE in the previous
equation is equal to zero volts.
R
=
R
+
–
V
V
g
g
CC
(15 + 5 − 2.5V)
EE
Rg
V
= 7ohm
≥
CC
= 15 V
= -5 V
Rg
OL
2.5 A
(V
= 18 V
CC
value of 2.5V in the previous equation is a conser-
Q1
Q2
− V
I
OLPEAK
Q1
Q2
EE
− V
OL
)
=
(V
CC
I
− V
OLPEAK
3-PHASE
+ HVDC
- HVDC
EE
AC
3-PHASE
− 2.5V )
+ HVDC
- HVDC
AC
OL
Peak Specifi-