SCALE™-2 1SC0450E2B0
Preliminary Description & Application Manual
www.power.com/igbt-driver
Page 16
Note, however, that it is not advisable to operate the power semiconductors within a half-bridge with a
driver in the event of a low supply voltage. Otherwise, a steep increase of V
CE
may cause partial turn-on of
these IGBTs.
Gate Boosting Power Supply (VGB)
The driver supports an increased IGBT turn-on voltage source VGB to perform gate boosting. The voltage is
generated by internal circuitry. No static load must be applied to VGB. Refer to the driver data sheet /3/ for
more information.
Gate Boosting Signal (GBS)
The gate-boosting signal GBS is an auxiliary signal that has the same time waveform – but different voltage
values – as the GH signal. Please refer to the driver data sheet for the exact voltage values /3/ and to the
”Gate Boosting” section for more information.
Note that no static load must be applied to GBS. Refer to the driver data sheet /3/ for more information.
Gate Drive Input (IN)
The gate drive input signal IN is inverted to the gate output. A transition to a low-level state at IN generates
a driver turn-on command while a transition to a high-level state generates a driver turn-off command. Also
It is recommended to use the input circuitry of Fig. 7. The drive signal is then not inverted to the gate
output according to Table 5.
If other drive circuits are used, the following information must be considered:
The absolute maximum ratings of the driver data sheet /3/ must be respected.
The logic level thresholds of the input IN are given in the driver data sheet /3/.
The input IN features an internal pull-up current source of about 500µA which sets its potential to a
high-level state and assures an IGBT off-state condition if the pin is floating. Refer to the driver data
sheet /3/ for values.
Pin IN belongs to the secondary-side electrical circuit and follows the emitter potential of the driven
IGBT. It must be isolated against primary-side circuits, e. g. with fiber-optic links.
Drive Signal T/R
(1)
Light Input IN Gate Output
Low
Off
High
Off-state
High
On
Low
On-state
Table 5 Signal input truth table correlated with the schematics of Fig. 7
Status Feedback /Fault input (OUT)
The OUT terminal is mainly used as a status feedback output. However, it also works as an input. When
OUT is externally shorted to COM for a minimum period of time (timing and threshold values according to
the driver data sheet /3/), the driver detects an external fault. The IGBT is then turned off after a delay
(1)
T/R: Transmitter and receiver pair of a fiber-optic link