Abstract: An LED driving device with an adjustable dimming depth is provided. The LED driving device includes an LED driver and a dimming depth control circuit. The LED driver includes a dimming control circuit and a driving circuit. The dimming control circuit generates a first pulse-width modulation (PWM) signal according to a first brightness indication signal. The driving circuit drives a first light source and adjusts a brightness of the first light source. A duty ratio of the first PWM signal and the first driving current have a first relationship therebetween. The dimming depth control circuit includes a first variable resistance circuit, and the first variable resistance circuit controls a magnitude of a first variable resistance between a first current sampling terminal and a ground terminal according to a first dimming depth control signal. The first relationship defines a first dimming depth that varies with the first variable resistance.

Abstract: A buffer circuit includes an input terminal configured to receive an input signal, an output terminal, an inverter, and a resistor-capacitor (RC) circuit coupled in series with the inverter between the input terminal and the output terminal. The RC circuit includes an NMOS transistor coupled between an RC circuit output terminal and a reference node, a resistor coupled between the RC circuit output terminal and a power supply node, and a capacitor coupled between the RC circuit output terminal and one of the power supply node or the reference node, and the inverter and the RC circuit are configured to generate an output signal at the output terminal based on the input signal.

Abstract: When an operation block is placed in a placing groove to electrically connect a connection module of the operation block to a control module that correspond in position to the placing groove, the control module sends an identification information of the operation block to a head-mounted display. The head-mounted display identifies the operation block according to the identification information thereof, and displays an augmented reality image corresponding to the operation block.