battery

A few months ago, Olimex unveiled renders of ESP32-S2-Devkit-LiPo WiFi board that was supposed to consume as little as 2uA in sleep mode, follows ESP32-S2-Saola-1 board form factor and pinout, and adds an ultra-efficient circuitry to support LiPo batteries. The good news is that Olimex has now launched two versions of their ESP32-S2 board optimized for battery-powered applications with ESP32-S2-DevKit-Lipo and ESP32-S2-WROVER-DevKit-Lipo (with 2MB PSRAM) going for 5.56 Euros and 6.36 Euros respectively. ESP32-S2-DevKit-LiPo specifications: Wireless module: ESP32-S2-DevKit-LiPo – ESP32-S2-WROOM with Espressif ESP32-S2 single-core 32-bit LX7 microprocessor up to 240 MHz with  128 KB ROM, 320 KB SRAM, 16 KB SRAM in RTC, 4MB SPI flash ESP32-S2-WROVER-Devkit-LiPo – ESP32-S2-WROVER – same as above plus 2MB PSRAM Wireless connectivity – 2.4 GHz 802.11 b/g/n WiFI 4 up to 150 Mbps Expansion – 2x 20-pin I/O headers with SPI, I2S, UART, I2C, touch sensors, PWM, etc… (pin-to-pin compatible with ESP32-S2-SAOLA-1) Debugging – […]

When we covered ESP32 powered TTGO T-Watch-2000 smartwatch this week-end, people noted that with a 350 mAh battery, the watch would last about 3.65 days considering a 4mA drain with the screen always off, WiFI and Bluetooth off, and around 65mA when the screen is on good for about 5 hours of continuous use without Bluetooth nor WiFi. But it’s possible to make a much more-efficient ESP32-S2 Wifi board, as demonstrated by Olimex with their upcoming ESP32-32-Devkit-LiPo based on ESP32-S2-Saola-1 with circuitry to support LiPo batteries. They designed the board with an ultra-low-power power supply circuit which makes current consumption during sleep only 6uA, 4 of which are due to the battery measurement resistor divider, meaning the board should consume only 2uA in sleep mode or about 10 times less than other ESP32 Olimex boards. When reviewed Qoitech Otii power measurement & DAQ tool, we also noted power consumption could […]