S-1142D33A-E6T2U Datasheet, PDF (14/31 Pages) Seiko Instruments Inc – Built-in thermal shutdown circuit

HIGH-WITHSTAND VOLTAGE LOW CURRENT CONSUMPTION LOW DROPOUT CMOS VOLTAGE REGULATOR
S-1142C/DxxA Series
Rev.1.1_01
5. Thermal shutdown circuit
The S-1142C/DxxA Series has a thermal shutdown circuit to protect the device from damage due to overheat.
When the junction temperature rises to 155°C typ., the thermal shutdown circuit operates to stop regulating. When
the junction temperature drops to 130°C typ., the thermal shutdown circuit is released to restart regulating.
Due to self-heating of the S-1142C/DxxA Series, if the thermal shutdown circuit starts operating, it stops regulating
so that the output voltage drops. When regulation stops, the S-1142C/DxxA 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 8
Thermal Shutdown Circuit
VOUT Pin Voltage
Operate: 155°C typ.^*1
Release: 130°C typ.^*1
VSS level
Set value
*1. Junction temperature
14