S1142A-H Datasheet, PDF (15/32 Pages) Seiko Instruments Inc – HIGH-WITHSTAND VOLTAGE LOW CURRENT CONSUMPTION LOW DROPOUT OPERATION CMOS VOLTAGE REGULATOR

HIGH-WITHSTAND VOLTAGE LOW CURRENT CONSUMPTION LOW DROPOUT 105°C OPERATION CMOS VOLTAGE REGULATOR
Rev.2.2_01
S-1142A/BxxH Series
5. Thermal shutdown circuit
The S-1142A/BxxH Series has a thermal shutdown circuit to protect the device from damage due to overheat.
When the junction temperature rises to 150°C typ., the thermal shutdown circuit operates to stop regulating. When
the junction temperature drops to 125°C typ., the thermal shutdown circuit is released to restart regulating.
Due to self-heating of the S-1142A/BxxH Series, if the thermal shutdown circuit starts operating, it stops regulating
so that the output voltage drops. When regulation stops, the S-1142A/BxxH Series does not itself generate heat
and the IC’s temperature drops. When the temperature drops, the thermal shutdown circuit is released to restart
regulating, thus this IC generates heat again. Repeating this procedure makes the waveform of the output voltage
into a pulse-like form. Stop or restart of regulation continues unless decreasing either or both of the input voltage
and the output current in order to reduce the internal power consumption, or decreasing the ambient temperature.
Table 10
Thermal Shutdown Circuit
VOUT Pin Voltage
Operate: 150°C typ.^*1
Release: 125°C typ.^*1
VSS level
Set value
*1. Junction temperature
15