Four commercial vehicle combination meter in state examine test table's external input voltage sampling circuit

The utility model discloses a four commercial vehicle combination meter in state examine test table's external input voltage sampling circuit, including an external input voltage, bleeder circuit, filter circuit, bleeder circuit comprises resistance R95, R99, and wherein R99 is adjustable resistance, filter circuit comprises resistance R96, electric capacity C3, the ADC passageway pin of singlechip is delivered to through bleeder circuit partial pressure, filter circuit post -filter to external input voltage, is turned into the analog quantity digital quantity and handles by the singlechip. The utility model discloses circuit structure is simple, and the function is stable, through the value that changes R99, obtains different sample?voltage benchmark. 本实用新型公开了国四商用汽车组合仪表检测台的外部输入电压采样电路，包括外部输入电压，分压电路、滤波电路，所述分压电路由电阻R95、R99构成，其中R99为可变电阻，所述滤波电路由电阻R96、电容C3构成；所述外部输入电压经分压电路分压、滤波电路滤波后送至单片机的ADC通道引脚，由单片机将模拟量转化为数字量并进行处理。本实用新型电路结构简单，功能稳定，通过改变R99的值，得到不同的采样电压基准。