Voltage regulator has dual input pins for low-power MCUs

Nisshinbo Micro Devices has launched the NR1620 series voltage regulator with dual input pins to supply low-power microcontroller cores and other applications.

The NR1620 has an output current of 150mA, allowing it to handle a wide range of applications and its quiescent current of 0.4 µA makes it suitable for systems that demand low power consumption and long battery operating times.

The input terminal for the regulator driver and internal control circuitry are separated, resulting in a Bias pin to connect a supply voltage for the internal error amplifier, reference voltage circuit, and gate control voltage for the N-channel driver.

The other VIN pin connects a supply voltage for the load. This innovative design allows the LDO to regulate very low input and output voltages.

The NR1620 boasts a ripple rejection of 90 dB, ensuring a fast and accurate response to input and output transients and achieving a stable output voltage.

The automatic mode-switching feature enhances battery life.

The device has a fast mode and a low-power operating mode.

The fast mode provides fast transient response and high performance of the LDO but requires a higher current consumption.

The low-power mode provides lower current consumption, albeit with a slower transient response as compared to the fast mode.

This mode-switching threshold is based on the current demand of the application, and the main benefit is that the enlarged current consumption only occurs when needed.

A fold-back current limit circuit is integrated and decreases the output current in case of a short circuit, protecting the LDO and other electronic parts of the application from damage.

An inrush current limit circuit prevents output voltage overshoots and undershoots during the start-up period.

The LDO has an optional auto-discharge function, and this feature rapidly discharges the output capacitor once the CE pin disables the chip.

The NR1620DC in a SOT-23-5 package is under development and expected to be available in May 2024, expanding its potential.

Specifications NR1620:

Quiescent Current: Typ. 0.4 μA

Output Voltage Accuracy: ±9.9 mV (Ta = 25°C)

Input Voltage Range (Maximum rating): VBIAS: 2.4 V to 5.5 V (6.5 V), VIN :0.6 V to VBIAS (6.5 V)

Output Voltage Range: 0.4 V to 1.2 V (0.1 V step)

Ripple Rejection: Typ. 90 dB (f = 1 kHz, Ripple in VIN), Typ. 60 dB (f = 100 kHz, Ripple in VIN)

Dropout Voltage: Typ. 150 mV (IOUT=150 mA, VSET=1.0 V,VBIAS=VSET+1.4 V)

Short-Circuit Current Limit: Typ. 110 mA

Ceramic Capacitors Supported: CIN, CBIAS, COUT (COUT: 2.2 μF to 100 μF)