【Application】Yangxing crystal provides 24MHz passive crystal for laser rangefinder, using 1612 ultra-small volume package, room temperature frequency difference ± 10ppm.

A laser rangefinder is a modern tool that utilizes a laser to make measurements that are more accurate to the target. A laser rangefinder emits a laser beam when measuring, and when it touches the target, the laser beam is reflected back, and the distance to the target is calculated using the speed of light and the reflection time.

The laser rangefinder contains the main control MCU, laser receiving module, laser transmitting module, LDO voltage regulator, ADC, LCD display, power supply and some peripheral devices. The main control MCU realizes the overall logic of the laser rangefinder, providing data display and controlling the laser transmitter and receiver modules. The high-precision external crystal provides the MCU with a stable clock frequency, which reduces the measurement error of the rangefinder and ensures the measurement accuracy.

Figure: Block diagram of laser rangefinder application principle

In the laser rangefinder project, the customer needs to use a passive crystal with a nominal frequency of 24MHz, 1612 ultra-small size, load capacitance of 8pF, and a frequency deviation of ±10ppm at room temperature to provide an accurate reference clock for the rangefinder's microcontroller. Based on the customer's project requirements, the XL4KI-111-24M of YXC's passive crystal oscillator YSX1612SL series is recommended, and the following figure shows the typical parameters of the XL4KI-111-24M:

YXC (Yangxing crystal) introduced passive crystal oscillator XL4KI-111-24M in the laser rangefinder application has the following characteristics:

① The nominal frequency is 24MHz, which meets the circuit design requirements of the laser rangefinder;

②Ultra-small, ultra-thin SMD metal packaged resonator, 1.6*1.2*0.35mm, greatly saving PCB space;

③ High precision, room temperature frequency difference (25 ℃) ± 10ppm, to provide a stable clock signal for the laser rangefinder, to help the laser rangefinder fast and accurate measurement;

③Wide temperature range, the working temperature supports -40~﹢85℃, which meets the working environment requirements of laser rangefinder.