MicroThe STC15W404AS-35I-SKDIP28 is an 8-bit single-chip microcontroller with an STC SKDIP-28 RoHS package manufactured by STC Micro. It features an 8051 core, up to 40 MIPS maximum operating frequency, up to 14 KB internal RAM, up to 15 KB internal ROM, and a maximum voltage of 4.0V. It can communicate with up to 256 external devices with its SPI and I2C buses, and features an 8-level priority interrupt support. It also has an on-chip WDT timer and multiple functions such as PWM/DAC, ADC, brown-out reset, power-saving mode, and power-on reset.