1ED020I12FA Datasheet, PDF (6/22 Pages) Infineon Technologies AG – Single IGBT Driver IC

EICEDRIVER®
1ED020I12FA
2
Functional Description
2.1
Introduction
The 1ED020I12FA is an advanced IGBT gate driver that can
be also used for driving power MOS devices. Control and
protection functions are included to make possible the design
of high reliability systems.
The device consists of two galvanic separated parts. The
input chip can be directly connected to a standard 5V DSP or
microcontroller with CMOS in/output and the output chip is
connected to the high voltage side.
An effective active Miller clamp function avoids the need of
negative gate driving in most applications and allows the use
of a simple bootstrap supply for the high side driver.
A rail-to-rail driver output enables the user to provide easy
clamping of the IGBTs gate voltage during short circuit of
the IGBT. So an increase of short circuit current due to the
feedback via the Miller capacitance can be avoided. Further,
a rail-to-rail output reduces power dissipation.
The device also includes an IGBT desaturation protection
with a FAULT status output.
A READY status output reports if the device is supplied and
operates correctly.
2.2
Internal Protection Features
2.2.2
READY status output
The READY output shows the status of three internal
protection features.
• UVLO of the input chip
• UVLO of the output chip after a short delay
• Internal signal transmission
It is not necessary to reset the READY signal since its state
only depends on the status of the former mentioned
protection signals.
2.2.3
Watchdog Timer
The 1ED020I12FA incorporates two level of signal
transmission security implemented through two independent
watchdog timers. First level ensures the short term signal
integrity by resending the (turn on/off) signals with a
watchdog period of typical 500ns. The second level monitors
during normal operation the internal signal transmission. If
the transmission fails for a given time, the IGBT is switched
off and the READY output reports an internal error.
2.2.4
Active Shut-Down
The Active Shut-Down feature ensures a safe IGBT off-state
if the output chip is not connected to the power supply.
2.2.1
Undervoltage Lockout (UVLO)
To ensure correct switching of IGBTs the device is equipped
with an undervoltage lockout for both chips.
If the power supply voltage V_VCC1 of the input chip drops
below V_UVLOL1 a turn-off signal is sent to the output chip
before power-down. The IGBT is switched off and the
signals at IN+ and IN- are ignored as long as V_VCC1 reaches
the power-up voltage V_UVLOH1 .
If the power supply voltage V_VCC2 of the output chip goes
down below V_UVLOL2 the IGBT is switched off and signals
from the input chip are ignored as long as V_VCC2 reaches the
power-up voltage V_UVLOH2 .
2.3
Non-Inverting and Inverting Inputs
There are two possible input modes to control the IGBT. At
non-inverting mode IN+ controls the driver output while IN-
is set to low. At inverting mode IN- controls the driver output
while IN+ is set to high. A minimum input pulse width is
defined to filter occasional glitches.
2.4
Driver Output
The output driver section uses only MOSFETs to provide a
rail-to-rail output. This feature permits that tight control of
gate voltage during on-state and short circuit can be
maintained as long as the drivers supply is stable. Due to the
low internal voltage drop, switching behaviour of the IGBT
is predominantly governed by the gate resistor. Furthermore,
it reduces the power to be dissipated by the driver.
Datasheet
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Version 2.1, 2009-11-24