S-1172B18-E6T1G Seiko Instruments, S-1172B18-E6T1G Datasheet - Page 16

• Manufacturer Part Number: S-1172B18-E6T1G
• Description: Low Dropout (LDO) Regulators Linear LDO reg Hi 70uA Iq 1000mA Iout
• Manufacturer: Seiko Instruments

Specifications of S-1172B18-E6T1G

• Polarity: Positive
• Input Voltage Max: 6 V
• Output Voltage: 1.8 V
• Output Type: Fixed
• Dropout Voltage (max): 3 V at 300 mA
• Output Current: 1000 mA
• Load Regulation: 15 mV
• Voltage Regulation Accuracy: 1 %
• Maximum Power Dissipation: 1900 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: HSOP-6
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

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HIGH RIPPLE-REJECTION LOW DROPOUT HIGH OUTPUT CURRENT CMOS VOLTAGE REGULATOR
S-1172 Series
5. Thermal shutdown circuit
6. Rush current control circuit
The S-1172 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 120°C (Typ.), the thermal shutdown circuit is released to restart regulating.
Due to self-heating of the S-1172 Series, if the thermal shutdown circuit starts operating, it stops regulating so that
the output voltage drops. When regulation stops, the S-1172 does not itself generate heat so that 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 waveform of the output voltage pulse-like form. Stop
/ Restart of regulation continues unless decreasing either / both of the input voltage and the output voltage in order
to reduce the internal current consumption, or decreasing the ambient temperature.
The S-1172 Series has a rush current control circuit to control the rush current generated during power-on or when
the ON/OFF pin is ON. This circuit limits the rush current (500 mA, Typ.) immediately after power-on or from the
ON/OFF pin is ON until the specified time (100 μs min.) which is set internally.
Caution
*1. Junction temperature
Thermal Shutdown Circuit
Operation : 150°C (Typ.)
Release : 120°C (Typ.)
The junction temperature drops to 120°C (Typ.) by the operation of thermal shutdown circuit,
after stopping regulation, the circuit is released to restart regulation; in this case, note that the
period to limit rush current may become shorter (10 μs min.).
*1
*1
Table 9
Seiko Instruments Inc.
VOUT Pin Voltage
Set value
V
SS
level
Rev.2.0
_00