New Product; R1801 Series, Buck DC/DC Switching Regulator with Ultra-low Quiescent Current of 200 nA and Minimum Starting Power of 1.00 μW, Optimal for Energy Harvesters

July 29, 2020
Ricoh Electronic Devices Co., Ltd.

Ricoh Electronic Devices Co., Ltd. has launched the R1801 series, an ultra-low quiescent current buck DC/DC switching regulator optimal for energy harvesters.

As the IoT market expands, it is more and more important to harvest small energy from ambient environment such as light, vibration and temperature, and to convert it into electricity.

The R1801 is a power-storing buck DC/DC switching regulator focused on storing electricity with a photovoltaic element. It achieves ultra-low quiescent current of typically 200 nA at normal temperature, high efficiency of typically 80% at 10 μA, and minimum starting power of 1.00 μW (VIN=4V, VOUT=3.0V).

The new DC/DC switching regulator can perform highly efficient extraction of electricity from a photovoltaic element thanks to a maximum power point control (MPPC) function and a reverse current protection function. The former function optimizes the efficiency of power supply from a photovoltaic element, and the latter cuts off the reverse-current path at no power supply to prevent power loss caused by reverse current.

The MPPC voltage and the output voltage are adjustable by pin setting, which is convenient when you determine the default voltage at the initial consideration or want to vary the MPPC voltage according to the actual environment.

Also, the R1801 has a power good (PG) function which monitors the output voltage. The PG signals enable grasping the power storage level, and therefore makes it easy to construct the power-supply sequence of the subsequent system.

The new IC adopts DFN(PLP)2730-12, which enables high-density mounting.

R1801
R1801 Series (DFN(PLP)2730-12)

Typical Characteristics of R1801 Series

R1801K003A (VOUT=3.3V)

R1801K003A

R1801K001A (VOUT=2.8V)

R1801K001A

Key Features of R1801 Series

1. Minimum Starting Power

The R1801 series achieves minimum starting power of 1.00 μW (VIN = 4 V, VOUT = 3.0 V). This enables storing electricity even under low-illuminance conditions.

2. Maximum Power Point Control (MPPC) Function

The MPPC function optimizes power supply from harvesters.
The MPPC voltage and the output voltage are adjustable by pin setting, which is convenient when you determine the default voltage at the initial consideration or want to vary the MPPC voltage according to the actual environment.

3. Power Good (PG) function

The PG function monitors the output voltage and outputs PG signals. The PG signals enable grasping the power storage level, and therefore makes it easy to construct the power-supply sequence of the subsequent system.
This function operates only by the VOUT power supply, so it can operate even at no light.

4. Ultra-low Quiescent Current and High Efficiency

The R1801 achieves ultra-low quiescent current of 200 nA and high efficiency of 80% at 10 μA simultaneously. This good balance allows using a photovoltaic panel with smaller cells.

5. Reverse Current Protection Function

The reverse current protection stops the current flowing from the COUT even at no power supply, and therefore enables the system to fully use the electricity extracted from a harvester.