Power Management ICs

5.5 V Input, 1000 mA Voltage Regulator S-1172 Series

The S-1172 Series, developed based on CMOS technology, is a positive voltage regulator with a super low dropout voltage (LDO), high output voltage accuracy, and low current consumption. The S-1172 Series provides the very small dropout voltage and the large output current due to the built-in transistor with low on-resistance. The overcurrent protector prevents the load current from exceeding the capacitance of output transistor. The thermal shutdown circuit prevents damage caused by heat, the rush current control circuit limits the excessive rush current during start-up. The ON/OFF circuit ensures longer battery life.

Compared with the voltage regulators using the conventional CMOS process, a large variety of capacitors are available, including small ceramic capacitors. High heat radiation HSOP-6 and small SOT-89-5 packages realize high-density mounting.


Output voltage
1.0 to 5.0 V, selectable in 0.05 V step.
Input voltage
1.5 to 5.5 V
Output voltage accuracy
±1.0% (1.0 to 1.45 V output product : ±15 mV)
Dropout voltage
70 mV typ. (3.0 V output product, IOUT=300 mA)
Current consumption
During operation: 70 µA typ., 90 µA max.(3.0 V output product)
During power-off: 0.1 µA typ., 1.0 µA max.
Output current
Possible to output 1000 mA (3.0 V output product, VIN ≥ VOUT(S) + 1.0 V)*1
Input and output capacitors
A ceramic capacitor of 4.7 μF or more can be used.
Ripple rejection
70 dB typ. (at 1.0 kHz, VOUT = 1.0 V)
Built-in overcurrent protection circuit   Limits overcurrent of output transistor
Built-in thermal shutdown circuit
Prevents damage caused by heat
Built-in inrush current control circuit
Limits excessive rush current during start-up
Built-in ON/OFF circuit
Ensures Longer battery life
Operation temperature range
Ta = −40°C to +85°C
Sn 100%

*1. Attention should be paid to the power dissipation of the package when the output current is large.


  • Constant-voltage power supply for battery-powered devices
  • Constant-voltage power supply for TV, notebook PCs and home electric appliances
  • Constant-voltage power supply for portable equipment

Standard Circuit

Standard Circuit