Shanghai Wansi Electronics Co., Ltd. is a high-tech company specializing in circuit board design, research, development, and production. We specialize in microcontroller development (including ST microcontroller, NXP microcontroller, ST, PIC, ATMEL, Zhongying, Zhaoyi Innovation, etc.), IoT applications (including 4G, 5G, Zigbee, Bluetooth, WiFi, etc.), development of AC and DC power monitoring systems, water quality detection, ammonia nitrogen, residual chlorine, dissolved oxygen, pH, conductivity, total copper, total phosphorus, total iron, permanganate detection, 4-20mA current treatment, 485 bus, analog quantity detection, motor control technology, flow detection, negative pressure detection, gas detection (including hydrogen sulfide, carbon monoxide), instruments and meters. Negative ion detection, dew point detection