|CPU||1x SiFive E24 Core 192 MHz|
|Storage||External SPI Flash (QSPI) or integrated 8Mbit - 32Mbit|
|Wireless||WiFi4, Bluetooth Low Energy 5.0, Bluetooth Low Energy Mesh|
|Peripherals||1x SPI Master/Slave, 2x UART, 1x I2C Master, 5x PWM max 40 MHz, 2x 10-bit DAC, 12x 12-bit ADC, PIR, SDIO Slave 2.0|
LF688 is IoTA microcontroller released in 2020 by LeapFive, and it belongs under BL602 series.
It seems to be rebranded BL604, with same pinout and feature-set. In LF688 SDK (not available), the structure is same as Bouffalo IoT SDK, just everything renamed to LeapFive and LF688.
Datasheets, Manuals, Documents
For more information, datasheets, manuals, check general information for BL602 series.