The STC15W402AS-35I-SOP28 is an 8-bit, low cost, low-power CMOS microcontroller produced by STC. It is packaged in a SOP-28_300mil RoHS compliant package. It features a 4KB or 32KB Flash Memory Program Memory, a 128B RAM, a 10-bit A/D converter, an Oscillator Start-up Time of 4 ms, a Power-On Reset Circuit, a Brown-Out Reset, a Low Voltage Reset, a Watchdog Timer, 8 I/O Ports and an interrupt handling capability. It is RoHS compliant, ensuring that it meets environmental standards and regulations. It is manufactured on an advanced 0.35um high performance CMOS process, which results in optimal speed and power consumption.