New Industry Products

Ricoh launches Buck DC/DC Converter with 200 nA quiescent current for Energy Harvesting applications

September 16, 2020 by Hailey Stewart

This article highlights Ricoh Electronics R1801 Buck DC/DC Converter, designed for use in the Internet of Things ecosystem by extracting energy from PhotoVoltaic or PiezoElectric cells.

Campbell, CA, September 16, 2020 - Ricoh Electronic Devices Co., Ltd. in Japan has launched the R1801 Buck DC/DC Converter, designed for use in the Internet of Things ecosystem by extracting energy from PhotoVoltaic or PiezoElectric cells. It is used to power small devices in applications such as wireless sensors, home and building automation, remote monitoring, presence detection and industrial equipment controls as well as wearables and fitness sensors.


Image courtesy of RICOH
Image courtesy of RICOH


The new R1801 makes small energy autonomous devices protecting the environment by reducing the use and waste of primary batteries, while eliminating the impact of cabling cost and maintenance to replace batteries regularly. A vast amount of these devices are to be deployed in environments such as offices, buildings, hotels, industrial sites, airports, malls, remote monitoring infrastructures and wearable fitness / healthcare devices.

The DC/DC converter converts energy and stores it in battery or super capacitor storage elements. An ultra-low quiescent current of 200 nA allows to use the harvester circuit even in a low-illuminated environment when the generated level of energy is moderate. As soon as there is sufficient energy available on the input side, the buck DC/DC Converter will be enabled to transfer energy from input to output until the energy drops below a threshold. This process repeats and increases the voltage in the energy storage device until the required level is reached.

The advanced R1801 has a few additional features like an adjustable maximum power point control and adjustable output voltage to make it possible to optimize the performance of the electrical circuit in combination with the selected type of the harvesters. The level is controlled in a 100mV step by the binary settings of three inputs and has a range of ±300mV. Furthermore a Power Good output is present to provide a logic signal as soon the output voltage reached a specific level and can be used to enable additional circuits for operation.

The minimum required power to start-up the IC is 1 µW and its peak efficiency is around 80% at 10 µA output current (ex. Vin=4V, Vout=3V).  A reverse current protection circuit prevents that a current flow will occur from output to input as soon the energy harvesting cell does not provide energy, the circuit is triggered when the input voltage drops below the output voltage. The R1801 is available in a DFN(PLP)2730-12 package.


Features R1801:  
Input Voltage Range: 2.2 to 5.5 V
Output Voltage Range:  2.2 to 4.5 V
Output Voltage Accuracy:   ± 3.0%
Maximum Power Point Control Voltage Range:   2.7 to 5.3 V
Operating Quiescent Current:  Typ. 200 nA (Ta = 25°C, at no load) (Vin = 4 V, Vout = 3.0 V)
Starting Power:    1 μW (Vin = 4 V, Vout = 3.0 V)
Protection Circuits:  Reverse Current Protection (Vin ≥ 2.0 V)
Other Features:   Adjustable Maximum Power Point Control
  Adjustable Output Voltage
  Power Good Function
Output Current   1 mA
Peak Efficiency    80% at 10 μA
Package R1801K            DFN(PLP)2730-12


About Ricoh Electronic Devices Co., Ltd

Ricoh Electronic Devices Co., Ltd is a leading global provider of semiconductor products, offering a comprehensive portfolio of CMOS Power Management and Real Time Clock ICs that enable engineers to design advanced applications for the consumer, industrial and automotive markets. The companies headquarter is based in Japan, as well as development, sales and manufacturing facilities. Regional sales and support offices are located in North America, Europe, and Asia.

Ricoh has an extensive expertise in small package technology and has a focus on developing products providing features such as low-supply current, high-accuracy, high efficiency and high-reliability.