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Page 23 of 34
IRAUDAMP10 REV
1.1
Over-Temperature Protection (OTP)
The over temperature protection input OTP is for an external PTC Thermistor to monitor
temperature of MOSFET. The OTP pin equips a 0.6mA internal current source to bias the external
PTC resistor. Over temperature warning activates when the voltage at any of OTP input pin goes
higher than 1.4V. Over temperature protection activates when the voltage at any of OTP input pin
goes higher than 2.8V. A PTC thermistors, Rpa in Fig 19, is placed on bottom side PCB; which is
close to the 4 DirectFETs; and monitors DirectFETs’ temperature. If the temperature rises above
90
C on the bottom side, make OTP input pin goes high and shuts down all 2 channels by pulling
down the CSD pins of the IRS2052M. OTP recovers once the temperature cools down.
On-chip Over Temperature Protection
If the junction temperature TJ of IRS2052M becomes higher than on-chip thermal warning
threshold 127
C, the on-chip over temperature protection pulls OTW pin down to GND. If the
junction temperature TJ keeps increasing and exceed on-chip thermal shutdown threshold 147
C,
the on-chip over temperature protection shuts down PWM, pulls OTW up to VAA and pulls FAULT
pin down to GND as long as the junction temperature is higher than the threshold.
Over Temperature Warning Output (OTW)
OTW output is an open drain output referenced to GND to report whether the IRS2052M is
experiencing high temperature from either OTP input or on-chip OTP. OTW activates if OTP pin
voltage becomes higher than warning threshold, or if junction temperature reaches warning
threshold.
Fault Output
FAULT output is an open drain output referenced to GND to report whether the IRS2052M is in
shutdown mode or in normal operating condition. If FAULT pin is open, the IRS2052M is in normal
operation mode.
Following conditions triggers shutdown internally and pulls FAULT pin down to GND.
• Over Current Protection
• Over Temperature Protection (internal or external via OTP pin)
• Shutdown mode from CSD pin voltage
Click and POP Noise Reduction
Thanks to the click and pop elimination function built into the IRS2052M, the IRAUDAMP10 does
not require any additional components for this function.