1ED020I12-F2 Datasheet, PDF (15/28 Pages) Infineon Technologies AG – Single IGBT Driver IC

EiceDRIVER™
1ED020I12-F2
Functional DescriptionNon-Inverting and Inverting Inputs
4.4
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, please see Figure 7. A
minimum input pulse width is defined to filter occasional glitches.
4.5
Driver Outputs
The output driver sections 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.
4.6
External Protection Features
4.6.1 Desaturation Protection
A desaturation protection ensures the protection of the IGBT at short circuit. When the DESAT voltage goes up
and reaches 9 V, the output is driven low. Further, the FAULT output is activated, please refer to Figure 8. A
programmable blanking time is used to allow enough time for IGBT saturation. Blanking time is provided by a
highly precise internal current source and an external capacitor.
4.6.2 Active Miller Clamp
In a half bridge configuration the switched off IGBT tends to dynamically turn on during turn on phase of the
opposite IGBT. A Miller clamp allows sinking the Miller current across a low impedance path in this high dV/dt
situation. Therefore in many applications, the use of a negative supply voltage can be avoided.
During turn-off, the gate voltage is monitored and the clamp output is activated when the gate voltage goes below
typical 2 V (related to VEE2). The clamp is designed for a Miller current up to 2 A.
4.6.3 Short Circuit Clamping
During short circuit the IGBTs gate voltage tends to rise because of the feedback via the Miller capacitance. An
additional protection circuit connected to OUT and CLAMP limits this voltage to a value slightly higher than the
supply voltage. A current of maximum 500 mA for 10 μs may be fed back to the supply through one of this paths.
If higher currents are expected or a tighter clamping is desired external Schottky diodes may be added.
4.7
RESET
The reset inputs have two functions.
Firstly, /RST is in charge of setting back the FAULT output. If /RST is low longer than a given time, /FLT will be
cleared at the rising edge of /RST, refer to Figure 8; otherwise, it will remain unchanged. Moreover, it works as
enable/shutdown of the input logic, refer to Figure 7.
Final Data Sheet
15
Rev. 2.0, 2011-08-01