25NP9000,4P30机芯,CPU.解码为TDA9370。故障现象为不开机,开盖检查超级芯片待机脚已输出待机指令 代换晶振.存储器无效。CPU各供电端及复位电压正常。后发现第36脚高电压检测端电压为2.2V偏高 (正常为1.5V),随断开R308(27K)测其阻值已增大到150K.换新R308后开机一切正常! |
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