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© 2021 ROHM Co., Ltd.
No. 64UG056E Rev.001
2021.10
User’s Guide
BD93E11GWL-EVK-001 (Stand-Alone)
Over temperature protection by an external PTC thermistor
This EVK has the over temperature protection using thermistor RTHD mounted on the board. The detection threshold of the
protection is set to 120°C and when the temperature around the PTC thermistor reaches the set temperature, the device turns off
the Nch-MOS FET (Q20 and Q21) on VBUS power line to isolate VBUS from the system safely. To enable this protection, connect
JP_OTP EN and ADSIN with a jumper pin.
Other than the temperature detected at RTHU, the over temperature protection can be triggered by the specific applied voltage
as defined in Table 4.
Table 4. The parameters of the OTP with PTC thermistor
Items
Detection temperature [°C]
120
Implemented PTC thermistor
as RTHU
MURATA PRF15BD102QB6RC
ON Threshold [V]
0.780
OFF Threshold [V]
0.470
Divided resistance RTHU [Ω]
22k
C3
t
°
RTHU
RTHD
JP_OTP
ADCIN
SGND
EN
ADCIN
VDD_CAP
SGND
SGND
Figure 11. OTP Schematic Circuit
