Sep 29, 2021
01:01 AM
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Sep 29, 2021
01:01 AM
The static charge current ICHGST and the static discharge current IDCHGST for static activation are used for two purposes:
1. These currents are used to charge and discharge the external MOSFETs, which are not controlled in PWM. These MOSFETs can be turned on and turned off faster than the MOSFET controlled in PWM, because the single activation is not relevant for the EMC characterization
2. IDCHGST is also used to turn off the MOSFETs in case of failure
In case of a short circuit detection, two criteria must be considered for the configuration of IDCHGST:
1. the MOSFETs must be turned off fast enough in order to stay within the safe operating area of the MOSFETs, considering the possible high drain-source current
2. the MOSFETs may not be turned off too fast, because a high current in combination with stray inductances and a fast turn off can trigger a MOSFET avalanche
That is the reason why IDCHGST is individually configurable for each half-bridge driver, so that these two criteria can be fulfilled for the considered MOSFET type.
1. These currents are used to charge and discharge the external MOSFETs, which are not controlled in PWM. These MOSFETs can be turned on and turned off faster than the MOSFET controlled in PWM, because the single activation is not relevant for the EMC characterization
2. IDCHGST is also used to turn off the MOSFETs in case of failure
In case of a short circuit detection, two criteria must be considered for the configuration of IDCHGST:
1. the MOSFETs must be turned off fast enough in order to stay within the safe operating area of the MOSFETs, considering the possible high drain-source current
2. the MOSFETs may not be turned off too fast, because a high current in combination with stray inductances and a fast turn off can trigger a MOSFET avalanche
That is the reason why IDCHGST is individually configurable for each half-bridge driver, so that these two criteria can be fulfilled for the considered MOSFET type.
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- IFX
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