IR2114SSPBF International Rectifier, IR2114SSPBF Datasheet - Page 17

• Manufacturer Part Number: IR2114SSPBF
• Description: IC DRIVER HALF-BRIDGE 24-SSOP
• Manufacturer: International Rectifier

Specifications of IR2114SSPBF

• Configuration: Half Bridge
• Input Type: Non-Inverting
• Delay Time: 440ns
• Current - Peak: 2A
• Number Of Configurations: 1
• Number Of Outputs: 2
• High Side Voltage - Max (bootstrap): 600V
• Voltage - Supply: 11.5 V ~ 20 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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2.3 Some Important Considerations
Voltage Ripple: There are three different cases to
consider (refer to Fig. 19).
In this case we have the lowest value for V
represents the worst case for the bootstrap capacitor
sizing. When the IGBT is turned off, the V
pushed up by the load current until the high side
freewheeling diode is forwarded biased.
In this case we have the highest value for V
on the high side IGBT, I
pulled up. To minimize the risk of undervoltage, the
bootstrap capacitor should be sized according to the
I
Bootstrap Resistor: A resistor (R
with the bootstrap diode (see Fig. 19) in order to limit
the current when the bootstrap capacitor is initially
charged. We suggest not exceeding 10
increasing the V
for charging the bootstrap capacitor or for refreshing its
charge must be verified against this time-constant.
Bootstrap Capacitor: For high t
electrolytic capacitor is used, its ESR must be
considered. This parasitic resistance forms a voltage
divider with R
at the first charge of bootstrap capacitor. The voltage
step and the related speed (dV
As a general rule, ESR should meet the following
constraint.
A parallel combination of a small ceramic capacitor and
a large electrolytic capacitor is normally the best
compromise, the first capacitor posses a fast time
constant and limits the dV
equivalent resistance. The second capacitor provides a
large capacitance to maintain the V
within the desired ∆V
Bootstrap Diode: The diode must have a BV > 600 V or
1200 V and a fast recovery time (t
LOAD
IGBT (resulting in V
and V
freewheeling diode
< 0 A case.
I
I
I
LOAD
LOAD
LOAD
CE
can be neglected
= 0 A; the IGBT is not loaded while being on
< 0 A; the load current flows in the low side
> 0 A; the load current flows through the
boot
V
V
BS
BS
, which generats a voltage step on V
BS
V
time-constant. The minimum on time
=
=
BS
BS
CEon
V
V
.
CC
=
CC
).
V
LOAD
−
−
CC
V
V
F
BS
−
BS
F
flows into it and V
HON
−
boot
/dt by reducing the
V
/dt) should be limited.
+
V
F
) is placed in series
V
CEon
designs where an
FP
BS
rr
< 100 ns) to
voltage drop
BS
s
. Turning
to avoid
BS
node is
. This
S
BS
is
17
minimize the amount of charge fed back from the
bootstrap capacitor to V
2.4 Gate Resistances
The switching speed of the output transistor can be
controlled by properly sizing the resistors controlling the
turn-on and turn-off gate currents. The following section
provides some basic rules for sizing the resistors to
obtain the desired switching time and speed by
introducing the equivalent output resistance of the gate
driver ( R
The example shown uses IGBT power transistors and
Figure 20 shows the nomenclature used in the following
paragraphs. In addition, V
voltage, Q
gate to emitter charge respectively.
2.5 Sizing The Turn-On Gate Resistor
Switching-Time: For the matters of the calculation
included hereafter, the switching time t
as the time spent to reach the end of the plateau
voltage (a total Q
IGBT gate). To obtain the desired switching time the
gate resistance can be sized starting from Q
Q
and
V
gc
ge
, Vcc , V
*
10%
DRp
t
Don
I
R
gc
V
avg
ge
TOT
t
CE
and R
1
,Q
*
and Q
10%
(see Fig. 21):
=
GE
90%
Figure 20: Nomenclature
=
Q
DRn
t
gc
Vcc
R
IR2114/IR2214SSPbF
ge
gc
+ Q
).
t
C
indicate the gate to collector and
I
+
sw
dV/dt
RES
ge
avg
−
CC
t
Q
SW
V
C
V
t
has been provided to the
2
supply.
ge
GE
RES
,Q
ge
*
V
ge
GC
GE
© 2009 International Rectifier
*
I
C
indicates the plateau
I
C
sw
is defined
ge
and
t,Q
C
C
RESon
RESoff