2RT0435T
Target Description and Application Manual
www.IGBT-Driver.com
Page 11
All inputs are ESD-protected. Moreover, all digital inputs have Schmitt-trigger characteristics.
MOD (mode selection)
The MOD input allows the operating mode to be selected.
Direct mode
If the MOD input is not connected (floating), or connected to VCC, direct mode is selected.
Half-bridge mode
If the MOD input is low level (connected to GND), half-bridge mode is selected. The dead time is set by a
resistor on the 2RT0435T.
TB (input for adjusting the blocking time)
The terminal TB allows the factory-set blocking time to be reduced by connecting an external resistor to GND
(see Fig. 8). The following equation calculates the necessary resistor R
b
connected between pins TB and GND
in order to define the desired blocking time T
b
(typical value):
8
.
6
]
[
99
]
[
150
7650
]
[
ms
Tb
ms
Tb
k
R
b
where 20ms <
T
b
< 90ms
The blocking time can also be set to a minimum of 9µs by selecting R
b
= 0
Ω
.
If not used, the input TB can be left open.
How Do 2RT0435T Base Boards Work in Detail?
Overview
All drivers of the SCALE-2 driver family with an electrical interface are equipped with usual protection functions
such as Vce monitoring for short-circuit protection, operation inhibit after fault, supply-undervoltage shutdown
and status feedback.
Outstanding features of 2RT0435T Base Boards are: compact size, simple mounting - directly to the IGBT
module over the interfaces X1/X2, Advanced Active Clamping function, minimum pulse suppression of input
signals, decoupling of failure outputs by MOSFET stage. Active clamping describes an active scheme designed
to protect the IGBTs against overvoltage during turn-off. It is particularly relevant when turning an IGBT off in
cases of high DC-link voltage and collector current or short circuit. The 2RT0435T Base Boards also allow
parallel operation of IGBT modules in order to increase the system power (see “Parallel connection of
2RT0435T” on page 13).