Basler daA1280-54bc, Руководство пользователя

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Hardware Design Recommendations AW00136902000
44 Basler dart BCON
6 Hardware Design
Recommendations
This chapter provides recommendations for designing your hardware to work with the Basler BCON
interface.
For more information about the BCON interface, see Section 4.2.1 on page 24 .
Identifiers such as X1, XCLK, CC0, or I2C_SDC refer to the pin names given in Section 4.2.1 on
page 24 .
6.1 BCON Data Output (X0, X1, X2, X3,
XCLK)
BCON uses four data lanes (X0 through X3) and one clock line (XCLK) to transmit image data from
the camera to the image processing unit.
During data transmission, signal reflections can be a major cause of bit errors. Every signal change
in the transmitter launches a wave that travels to the receiver. If the termination resistor at the other
end of the trace matches the impedance of the differential trace, it consumes most of the energy of
the wave.
Therefore, both the differential traces and the termination resistors must have an impedance of
100 ohm. If they do not match the target impedance, the reflected wave can disturb the original
signal and cause bit errors.
Design Recommendations for Data Transmission
Printed Circuit Board (PCB)

Design the PCB to have a differential impedance of 100 ohms. If this is not possible, make the
traces between the connector and the receiver as short as possible.

Run the differential traces as close as possible, but leave a gap of at least three trace widths
between the individual pairs.

Ensure that the two traces of a differential pair have the same length. A mismatch of 5 mm or
less is not critical.

Ensure that the lengths of all pairs do not differ more than 20 mm.

Place a 100 ohm termination resistor across the traces of each pair as close to the receiver's
pins as possible.