Overtemperature Hardware Protection Circuit; Ntc Shutdown Value Calculation And Configuration - Infineon iMOTION EVAL-M3-IM564 User Manual

EVAL-M3-IM564 User Manual
iMOTION™ Modular Application Design Kit
Hardware description of EVAL-M3-IM564
4.3.2

Overtemperature hardware protection circuit

The VFO pin not only provides direct access to the NTC, but also indicates a module failure in case of under-
voltage at pin VDD or in case of triggered overcurrent detection at ITRIP. In these evaluation design kits EVAL-
M3-IM564 and EVAL-M3-102T, the VFO pin is directly connected to the gatekill pin for controller IC IMC102T.
But for the iMOTION™ 100 series control board, the maximum input low voltage of gatekill for IRMCF1xx is 0.8 V.
The NTC thermal resistor is about 3.0 kΩ at 120 °C. The resistors R44 and R45 for the power board EVAL-M3-
IM564 are chosen properly to make sure the voltage of VFO is 0.8 V at 120 °C. The gatekill will then "ask" the
microcontroller to stop generating PWM pulses if the temperature of NTC continues to rise.
VTH
Equivalent circuit
Figure 27 Overtemperature protection circuit schematic for EVAL-M3-IM564 and EVAL-M3-102T
4.3.3

NTC shutdown value calculation and configuration

External NTC temperature shutdown value can be calculated as shown below and configured in MCEWizard as
shown in Figure 28. For pull-up resistors on the evaluation control board, please refer to the control board's
User Manual. For example, for EVAL-M3-102T, the pull-up resistor on the control board is 4.87 kΩ. The value of
resistors R44 and R45 on EVAL-M3-IM564 are 9.1 kΩ and 10 kΩ (see Figure 27). The typical value of R
is 5.388 kΩ for IPM IM564-X6D/IM564-X6DS, which is used in EVAL-M3-IM564.
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User Manual
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Revision 1.4
2020-07-16