R1191x Series

300mA LDO Regulator with the Reverse Current Protection for Automotive Applications


Data Sheet

Data Sheet

R1191x Series are a low supply current voltage regulator with high output voltage accuracy. The maximum operating voltage is 16V. These ICs can switch to the fast mode and the low power mode by the low power / fast mode changer pin (ECO pin) without changing the output voltage value.
Each of these ICs consists of a voltage reference unit, an error amplifier, a resistor-net for voltage setting, a short current limit circuit, a thermal shutdown circuit and a chip enable circuit.
Moreover, the R1191x Series has the reverse current protection function, which protects the reverse current flow into VDD pin when the output pin voltage becomes higher than the VDD pin voltage. Thus it is suitable for the back-up circuit.
Since the packages for these ICs are SOT-89-5 and SOT-23-5, therefore high density mounting of the ICs on boards is possible.


Input Voltage Range (Maximum Rating) 3.5V to 16.0V (18V)
Supply Current Typ. 50µA (Fast Mode),
Typ. 6.0µA (Low Power Mode)
Standby Mode Typ. 0.3µA
Reverse Current Max. 0.1µA
Output Current Min. 300mA
Output Voltage Range 2.0V to 15.0V (0.1V steps)
Output Voltage Accuracy ±1.5% (Fast Mode)
±2.5% (Low Power Mode)
Temperature-Drift Coefficient of Output Voltage Typ. ±80ppm/°C
Dropout Voltage Typ. 0.55V (Fast Mode, IOUT=300mA, VOUT=5.0V)
Typ. 0.70V (Low Power Mode, IOUT=300mA, VOUT=5.0V)
Ripple Rejection Typ. 60dB (f=1kHz,VOUT=5.0V, Fast Mode)
Line Regulation Typ. 0.02%/V (Fast Mode)
Packages SOT-23-5, SOT-89-5
Built-in fold-back protection circuit Typ. 50mA (Current at short mode)
Built-in Thermal Shutdown Circuit Shutdown Temperature at 150°C
Ceramic capacitors are recommended to be used with this IC CIN=2.2µF or more, COUT=4.7µF or more


  • Power source for accessories such as car audios, car navigation systems, and ETC systems

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Data Sheet Package Quality Assurance Data Suffix Composition & Content*1
R1191x Series
SOT-23-5 Reliability -AE Sn (Sn: 100%)
SOT-89-5 Reliability -AE Sn (Sn: 100%)
  • *1The composition of the product cannot be specified.

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