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一、双线控制(I~2C)总线彩电常见故障的修理方法 I~2C总线是一种串行的数据总线,总线各集成电路或模块通过一条串行的数据线(SDA)和另一条串行的时钟线(SCL),按照一定通讯协议进行寻址和信息的传输,其正常工作时,电压值大都在5 V左右(稳定),当其在数据的传输过程中电压才有下降和抖动。其常见故障有以下几种: 1.SDA和SCL信号线都在5 V左右抖动,对于采用应答方式的通信,CPU只有接收到被控IC的应答信号,才认为该IC正常。当其传输线路断开时,CPU接收不到应答信号,于是重复传输数据造成总线电压抖动。对于不采用应答方式的通信,则不会发生此故障,所以一般认为此类故障是由于传输线路断路造成的。 2.SDA和SCL有一个电压很低,这是由于该信号被对地短路造成的。检修该类故障时,需逐一断开该
First, the two-wire control (I ~ 2C) bus TV repair common faults I ~ 2C bus is a serial data bus, the bus of each integrated circuit or module through a serial data line (SDA) and another string Line of the clock line (SCL), in accordance with a certain communication protocol for addressing and transmission of information, its normal work, the voltage value is mostly about 5 V (stable), when the data transmission in the process of voltage drop and jitter . The common faults are the following: 1.SDA and SCL signal lines are jitter around 5 V, for the response mode of communication, the CPU only receives the response signal of the accused IC, that the IC is normal. When the transmission line is disconnected, the CPU can not receive the response signal, so repeated transmission of data causes bus voltage jitter. This type of failure does not occur for communications that do not use answering methods, so it is generally accepted that such a failure is caused by a broken transmission line. 2.SDA and SCL have a very low voltage, which is due to the signal is caused by a short circuit. Maintenance of such failures, the need to disconnect the one by one