Renesas launches SOTB process embedded flash memory low-power technology for energy harvesting and battery-free power supply
Renesas launches SOTB process embedded flash memory low-power technology for energy harvesting and battery-free power supply
Renesas Electronics Co., Ltd. launched a new low-power embedded flash memory based on 65nm SOTB technology, which can provide 1.5mb capacity. The industry's first embedded 2t-monos flash memory based on 65nm SOTB technology. By introducing new circuit technology to reduce the power consumption of the flash memory peripheral circuit, the read power consumption at 64 MHz operating frequency is as low as 0.22 pJ/bit-the industry's lowest-level embedded flash memory on the MCU. The low power consumption technology of the peripheral circuit includes: (1) Reduce the energy consumption when detecting the data in the memory; (2) Reduce the transmission energy consumption when sending the read data to the outside world. This advanced technology helps to greatly reduce the read storage Energy consumption in data transfer.
Renesas Electronics presented the test results at the 2019 VLSI and Circuit Technology Symposium (June 9-14, 2019) held in Kyoto, Japan on June 12.
The new SOTB-based technology has been used in the rissa R7F0E embedded controller, which is specifically designed for energy harvesting applications. Renesas’ unique SOTB technology significantly reduces operating and standby power consumption. Generally speaking, the power consumption in these two states increases and decreases each other: that is, the lower the power consumption of one, the higher the power consumption of the other. The new technology drastically reduces the power consumption when reading data from flash memory. Compared with non-sotb 2t-monos flash (approximately 50 microns/MHz read current), the new technology can achieve a read current of only about 6 microns/MHz, which is equivalent to 0.22 pJ/bit of read energy consumption, reaching the MCU The lowest level of energy consumption for embedded flash memory. The new technology also helps to achieve a low effective reading current of 20 microns/MHz on the R7F0E, the best in the industry.
The main features of the new embedded flash memory technology:
Low-power 2T-MONOS flash memory mainly suitable for SOTB process
SOTB 2t-monos embedded flash memory has a two-transistor structure that contains electrical isolation elements. Unlike the single-transistor structure, there is no negative voltage during read operations, thereby reducing power consumption when reading data. In addition, MONOS uses fewer masks in production than other memory processes, and can use a discrete charge capture scheme to store data, thereby achieving low power consumption and high rewrite reliability without increasing production costs.
Used for ultra-low energy sensing amplifier circuit and voltage stabilizing circuit technology
Most of the energy consumption in the memory reading process occurs in the sensing operation of the identification data and the output of the identification data to the outside. To solve this problem, the single-ended sense amplifier significantly reduces the bit line precharge energy in the sensing process. The new charge transfer technology improves the precharge speed and energy efficiency in a constant manner. These advanced technologies not only greatly reduce energy consumption, but also speed up sensing operations.
Renesas Electronics' circuit technology to significantly reduce data transmission power consumption
One of the characteristics of the SOTB process is to minimize the fluctuation of the transistor threshold (Vth). The new technology uses this advantage to achieve data transmission with extremely small voltage amplitudes. When the read data is sent out, this technology significantly reduces the energy consumption of the transmission.
