What is the difference between differential line transceiver & differential line driver and receiver pairs ?
Line transceiver is used as translator in either unidirectional or bidirectional; whereas line driver receiver pairs is used to produce differential output and convert back to single-ended at the output. Am I correct ?
Electronic – Difference between differential line transceiver & differential line driver and receiver pairs
transceiver
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The terminology is vague at best. There are no hard and fast rules, and nobody playing police when people don't use the term correctly.
Usually, but not always, a transceiver is a simple buffer that has different signal standards on the inputs and outputs. For example, an RS-232 transceiver usually interfaces TTL signals to RS-232 signals. Also, transceivers are similar to "drivers" and "receivers" except that a transceiver usually does both driver and receiver functions in the same chip.
A Phy is similar to a transceiver in that there is usually different signal standards on "both sides of the chip". With Ethernet it is MII/GMII/etc on one side and, well, Ethernet on the other. There are other Phy's that talk USB, PCIe, and many others. Phys usually incorporate some sort of SERDES (SERializer-DESerializer) function and line encoding. More sophisticated PHYs contain a mini-DSP in them to do all sorts of crazy communication things like advanced baseband wander correction.
A transceiver does not have to be associated with a serial data-- they can be used for parallel data as well. A PHY usually involves some sort of serial data stream. But this is more of a convention than a rule, and I am sure there are chips out there that are exceptions to this.
The transmitters don't transmit at exactly the same frequency - there may be tens of kHz difference - the receiver however is matched to the transmitter and, from what I know and have read about these particular devices, there is a manual adjuster on the receiver to bring it into near-perfect alignment with the transmitter it is paired with.
Notice the screw terminal on the receiver - this is, I believe, an adjuster that can align the receiver's operating frequency with the transmitter. Basically this means that two randomly chosen transmitters are unlikely to be at the same frequency and, as a result, one setting of the screw on the receiver will not suit both transmitters.
They are $5 a pair so you get what you pay for.
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Best Answer
A differential driver generates a differential signal with complementary (+,-) sides. A differential receiver receives a differential signal; that received signal is the difference between the + and - halves. For example, +0.25 - (-0.25V) = 0.5V differential signal.
A differential driver can convert a single-ended signal to differential, but it can equally merely buffer another differential signal. Differential signals are commonly generated and received on some inputs, outputs and IOs of large devices such as microprocessors. Differential signals are used because they are more resistant to noise and capable of carrying high-bitrate signals more reliably.
A differential transceiver is a combination of the driver and receiver described above. In this case, the driver part can be disabled, so that it has no appreciable effect on the connected differential line. The transceiver then acts purely as a receiver. If the driver part is enabled, then the receiver continues to receive, but the internal logic behind it will often not be reading the signal at that time.
Most modern PCs contain a PCI Express (PCIe) bus that uses differential signalling. PCIe uses Dual Simplex signalling, so that signals generated by differential drivers are received by differential receivers.
By contrast, the bidirectional, differential DQS+/DQS- strobe signal in DDR3 memory, uses differential transceivers (actually pseudo-differential, but that does not matter in this discussion). The strobe can be transmitted either from memory to controller or from controller to memory, depending on which differential transceiver is switched on at any time.