~ Achieves the Highest Levels of Low Noise, High PSRR, Low Quiescent Current and Fast Response Characteristics ～

Optimized for Use in Consumer and Industrial Applications, High Output Current of 1 A, NR1641 Series: LDO Voltage Regulator

NISD has launched a new LDO voltage regulator NR1641 series for use in consumer and industrial applications.

High-performance sensors, such as CMOS image sensors, and devices used in high-end audio and video equipment are becoming increasingly sensitive to noise. In particular, power supply noise can directly affect the performance of these devices, and noise suppression is essential to maximize the performance.。

The NR1641 series is an ultra-low noise LDO voltage regulator with an output noise voltage of 3.7 μVrms, which is the world's highest level* for products that do not require noise reduction capacitors, and offers a high ripple rejection ratio of 80 dB (f = 10 kHz). It also has a built-in "soft-start function," which controls the slope of the output voltage at start-up. This function is expected to have effects such as suppressing inrush currents and simplifying control when there are restrictions on the power supply input to devices in the subsequent circuit. In addition, it supports a high output current of 1 A, and by using a built-in fast / low power automatic alternative mode, both low quiescent current and fast response can be achieved.

These functions provide clean power supplies with low noise to any noise sensitive devices, including high-performance ones that require large current, such as high-performance sensors and image processing LSIs, and those that are required to save power with battery operation, such as RF devices using VCOs (voltage controlled oscillators).

The input voltage of the product ranges from 1.7 V to 5.5 V, and output voltage variations are available from 1.0 V to 5.0 V in 0.1 V increments. It is possible to select whether or not to use the function of discharging capacitors in the subsequent circuit using the enable pin when the output is turned off, and to select the output voltage slope of the soft-start function at start-up from two different types.

Three types of packages are available for this product: DFN1616-6-GY (1.6 x 1.6 x 0.4 mm), a good balance of area and power dissipation package; HSON-6-GU* (2.9 x 3.0 x 0.9 mm), a high power dissipation package; and WLCSP-6-P12** (1.3 x 0.88 x 0.36 mm), an ultra-small package, allowing you to select the most suitable package for applications.
* HSON-6-GU is under development and will be available in 2024.
** WLCSP-6-P12 is under development. Release date has not yet been scheduled.

1. Selectable Fast / Low Power Automatic Mode Alternative Function and Fixed Fast Mode Function by External Control

2. Noise and High Ripple Rejection without Requiring a Noise Reduction Capacitors

The NR1641's automatic mode alternative function achieves both low quiescent current and ultra-low noise & fast response according to the output current. In addition, the function can be switched to the fixed fast mode by setting the MODE pin to "High," improving response performance at any time. In addition, while low-noise LDOs with high output current for analog power supplies generally require many external components, the NR1641 series is an ultra-low noise LDO voltage regulator with the output noise voltage of 3.7 μVrms, which is the world's highest level* for products that do not require noise reduction capacitors and offers the high ripple rejection ratio of 80 dB (f = 10 kHz).

3. Two Selectable Slopes of Output Voltage Simplifying Countermeasures against Inrush Currents

Depending on the device used, it may have restrictions on the slope of output voltage at start-up or may require countermeasures against malfunctions caused by an inrush current due to a large capacitance in the subsequent circuit. The NR1641 series has the soft-start function that allows users to select the slope of the output voltage from two different types. In addition, even with a large output capacitor, the inrush current is limited to typ. 250 mA until output voltage start-up is completed, which simplifies countermeasures against inrush current.

NR1641GY Series (DFN1616-6-GY)