RT6253A/B
discharge the energy of output inductor. This behavior
can keep the valley of negative current at NOC
threshold to protect low-side MOSFET. However, the
negative current can’t be limited at NOC threshold
anymore since minimum off-time is reached.
Thermal Shutdown
The
RT6253A/B
includes
an
over-temperature
protection (OTP) circuitry to prevent overheating due to
excessive power dissipation. The OTP will shut down
switching operation when junction temperature
exceeds a thermal shutdown threshold (T
SD
). Once the
junction temperature cools down by a thermal
shutdown hysteresis (T
SD
), the IC will resume normal
operation with a complete soft-start.
Note that the over temperature protection is intended to
protect the device during momentary overload
conditions. The protection is activated outside of the
absolute maximum range of operation as a secondary
fail-safe and therefore should not be relied upon
operationally. Continuous operation above the
specified absolute maximum operating junction
temperature may impair the reliability of the device or
permanently damage the device.
Copyright © 2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
6
DS6253A/B-01
September
2019
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
