1. Adopt 32-bit high-speed ARM chip as the main control chip STM32F407, the main frequency is up to 168MHz, and it comes with FPU floating point arithmetic unit. (Compared with ROBIN's STM32F103 (72MHZ) and other (16MHZ), the data processing capacity is stronger and the speed is faster) 2. the circuit board adopts high-quality 2-layer board and specially optimized heat dissipation treatment 3. Using high-quality MOSFET tubes, the heat dissipation effect is better 4. Use a dedicated power chip to support 12-24V power input 5. It can accept 24V input, and the hot bed current can be reduced to 1/4 under the same system power, which effectively solves the heating problem of the hot bed MOS tube Product parameters: Product Name: ET4 Pro Mute Motherboard Microprocessor: STM32F407 Input voltage: 8V-35V Motor driver: A4988/TMC2208 Sensor type: 100K thermal resistance Press screen: 2.8 inches TFT Firmware update: support TF card, U disk update Printing : support offline printing, online printing Resume after power failure: Yes Broken material detection: yes Colour:Black Material:PCB+metal Size:90x70mm Package Contents: 1 * ET4 Pro silent motherboard Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.