Echo suppression circuit for rail transit

The utility model discloses an echo suppression circuit for rail transit. The circuit comprises a chip with a model number of FM1288GA11010, a passive crystal oscillator with a model number of 18.432MHZ, and an EEPROM chip with a model number of AT24C64DSSHMT. The echo suppression chip can suppress echoes to a certain extent, the software SAMTunerV2 is used for adjusting and setting parameters according to different environmental conditions on site, the parameters are stored in the EEPROM chip, the working state of the chip is judged according to the indicator light, gains of the MIC and theSPK can be adjusted according to actual conditions, the upper limit of the MIC and the SPK can be adjusted to be +/-20db, and the echo is suppressed. Increasing or decreasing output power. 本实用新型公开了一种轨道交通用回音抑制电路。电路包括型号为FM1288-GA1-410的芯片、型号为18.432MHZ的无源晶振、型号为AT24C64D-SSHM-T的EEPROM芯片；利用回音抑制芯片可以在一定程度上对回音进行抑制，根据现场不同的环境情况，利用软件SAMTunerV2进行调节，设置参数，存储于EEPROM芯片中，根据指示灯判断芯片工作状态，并且根据实际情况还可以调节MIC和SPK的增益，调节上限为±20db，在抑制回音的同时，增大或减小输出功率。