SKHI24 Datasheet, PDF (6/8 Pages) Semikron International – Hybrid Dual IGBT Driver

Gate driver
The output transistors of the power drivers are MOSFETs.
The sources of the MOSFETs are separately connected to
external terminals in order to provide setting of the turn-on
and turn-off speed by the external resistors R_ON and R_OFF.
Do not connect the terminals ST1 with ST2 and SB1 with
SB2, respectively. The IGBT is turned on by the driver at
+15V by R_ON and turned off at – 8 V by R_OFF. R_ON and R_OFF
may not chosen below 1,5 Ω. In order to ensure locking of
the IGBT even when the driver supply voltage is turned off,
a 22 kΩ-resistor versus the emitter output (E) has been
integrated at output G_OFF.
V_CE-monitoring
The V_CE-monitoring controls the collector-emitter voltage
V_CE of the IGBT during its on-state. V_CE is internally limited
to 10 V. If the reference voltage V_CEref is exceeded, the
IGBT will be switched off and an error is indicated. The
reference voltage V_CEref may dynamically be adapted to
the IGBTs switching behaviour. Immediately after turn-on
of the IGBT, a higher value is effective than in the steady
state. This value will, however, be reset, when the IGBT is
turned off. V_CEstat is the steady-state value of V_CEref and is
adjusted to the required maximum value for each IGBT by
an external resistor R_CE to be connected between the
terminals C_CE (ST4/SB4) and E (ST3/SB3). It may not
exceed 10 V. The time constant for the delay of V_CEref may
be increased by an external capacitor C_CE, which is
connected in parallel to R_CE. It controls the time t_min which
passes after turn-on of the IGBT before the
V_CE-monitoring is activated. This makes possible any
adaptation to the switching behavior of any of the IGBTs.
After t_min has passed, the V_CE-monitoring will be triggered
as soon as V_CE > V_CEref and will turn off the IGBT.
External components and possible adjust-
ments of the hybrid driver
Dimensioning of R_CE and C_CE can be done in three steps:
1. Calculate the maximum forward voltage from the
datasheet of the used IGBT and determine V_CEstat.
2. Calculate approximate value of R_CE according to
equation (1) or (1.1) from V_CEstat or determine R_CE by
using fig. 3.
3. Determine t_min and calculate C_CE according to equations
(2) and (3).
Typical values are
for 1200V IGBT: V_CEstat = 5 V; t_min = 1,45 µs,
R_CE = 18 kΩ, C_CE = 330 pF
for 1700V IGBT:V_CEstat = 6 V; t_min = 3 µs,
R_CE = 36 kΩ, C_CE = 470 pF
Adaptation to 1700 V IGBT
When using 1700 V IGBTs it is necessary to connect a
1 kΩ / 0,4 W adaptation resistor between the
V_CE-terminal (ST9/ SB9) and the respective collector.
Adaptation to error signal level
An open collector transistor is used as error terminal,
which, in case of error, leads the signal to earth. The signal
has to be adapted to the evaluation circuit voltage level by
means of an pull-up resistor. The maximum load applied
to the transistor shall be 30 V / 15 mA.
IGBT switching speed adjustment
The IGBT switching speed may be adjusted by the
resistors R_ON and R_OFF. By increasing R_ON the turn-on
speed will decrease. The reverse peak current of the
free-wheeling diode will diminish. SEMIKRON
recommends to adjust R_ON to a level that will keep the
turn-on delay time t_d(on) of the IGBT < 1 µs. By increasing
R_OFF the turn-off speed of the IGBT will decrease. The
inductive peak over voltage during turn-off will diminish.
Fig. 1 shows the required external components for
adjustment and adaptation to the power module.
V_CE - monitoring adjustment
The external components R_CE and C_CE are applied for
adjusting the steady-state threshold and the short-circuit
monitoring dynamic. R_CE and C_CE are connected in
parallel to the terminals C_CE (ST4/ SB4) and E (ST3/ SB3)
.
The minimum gate resistor value for R_OFF and R_ON is
1,5 Ω. Typical values for R_ON and R_OFF recommended by
SEMIKRON are given in fig. 4.
Interlock time adjustment
Fig. 2 shows the possible interlocking times between
output1 and output2. Interlocking times are adjusted by
connecting the terminals TDT1 (P13), TDT2 (P14) and
SELECT (P15) either to earth/ GND (P16) according to the
required function or by leaving them open.
8
SK-IGBT-Modul
R_Gon R_Goff C_CE R_CE R_VCE
7
Ω
Ω pF kΩ kΩ
6
SKM 50GB123D
22 22 330 18
0
5
SKM 75GB123D
22 22 330 18
0
4
Vcestat without Rvce (1200V
application)
SKM 100GB123D
15 15 330 18
0
3
SKM 145GB123D
12 12 330 18
0
2
Vcestat / V mit Rvce = 1 kOhm
(1700V application)
SKM 150GB123D
12 12 330 18
0
1
SKM 200GB123D
10 10 330 18
0
0
10
20
30
40
50
60 ^{SKM 300GB123D}
8,2 8,2 330 18
0
Rce in kOhm
SKM 400GA123D
6,8 6,8 330 18
0
Fig. 3 V_CEstat in dependence of R_CE
1920 Driver Electronic – PCB Drivers
SKM 75GB173D
15 15 470 36
1
22-08-2003 © by SEMIKRON