The DS90UB638-Q1 receives CSI-2
formatted data on an FPD-Link III input port and forwards the data to the CSI-2
transmit port. The deserializer can operate in
CSI-2 mode with synchronous back channel reference or non-synchronous mode. The
forward channel line rate is independent of the CSI-2 rate in synchronous or
non-synchronous with external clock mode. The CSI-2 mode supports remapping
of Virtual Channel IDs at the input of the receive port.
The deserializer Rx Port can support an FPD-Link
line rate up to 4.16 Gbps, where the forward channel and back
channel rates are based on the reference frequency used for the serializer:
- In Synchronous mode based on REFCLK input
frequency reference, the FPD-Link line rate is a fixed value of 160 ×
REFCLK. FPD3_PCLK = 4 × REFCLK and Back channel rate = 2 × REFCLK. For
example with REFCLK = 25 MHz, line rate = 4.0 Gbps, FPD3_PCLK = 100 MHz,
back channel data rate = 50 Mbps. The sensor CSI-2 rate is independent of
the line rate and Tx CSI-2 rate in synchronous clocking mode and can be up
to 3.328 Gbps.
- In Non-synchronous clocking mode when the DS90UB635-Q1 uses external
reference clock (fCLKIN) the FPD-Link line rate is typically
fCLKIN × 80, FPD3_PCLK = 2 × fCLKIN or 1 x
fCLKIN and back channel data rate is set to 10 Mbps. For
example, with fCLKIN = 50 MHz, line rate = 4Gbps, FPD3_PCLK = 100
MHz, and the back channel rate is 10 Mbps. The sensor CSI-2 rate is
independent of the fCLKIN.