irs2609d International Rectifier Corp., irs2609d Datasheet - Page 12

• Manufacturer Part Number: irs2609d
• Description: Half-bridge Driver
• Manufacturer: International Rectifier Corp.

Negative V
A common problem in today’s high-power switching converters is the transient response of the switch node’s voltage as the power
switches transition on and off quickly while carrying a large current. A typical 3-phase inverter circuit is shown in Figure 12; here we
define the power switches and diodes of the inverter.
If the high-side switch (e.g., the IGBT Q1 in Figures 13 and 14) switches off, while the U phase current is flowing to an inductive load,
a current commutation occurs from high-side switch (Q1) to the diode (D2) in parallel with the low-side switch of the same inverter
leg. At the same instance, the voltage node V
Also when the V phase current flows from the inductive load back to the inverter (see Figures 15 and 16), and Q4 IGBT switches on,
the current commutation occurs from D3 to Q4. At the same instance, the voltage node, V
to the negative DC bus voltage.
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S
Transient SOA
Figure 13: Q1 conducting
Figure 15: D3 conducting
OFF
ON
Q1
Q2
DC+ BUS
V
DC- BUS
S1
D2
I
U
S1
, swings from the positive DC bus voltage to the negative DC bus voltage.
Figure 12: Three phase inverter
Figure 14: D2 conducting
Figure 16: Q4 conducting
OFF
OFF
OFF
ON
Q1
Q2
Q3
Q4
DC+ BUS
DC+ BUS
V
DC- BUS
V
DC- BUS
S1
S2
S2
, swings from the positive DC bus voltage
D1
D2
D3
IRS2609DSPbF
I
U
I
V
12