9.6.2Differential PECL output

The serial PECL output signal voltage characteristics are provided in Table 26. The outputs are not AC coupled in order to deliver maximum signal without rise and fall time degradation. You must AC couple the receiver to isolate potentially different DC characteristics of the outputs and the receiver.

Table 26:

Differential PECL output characteristics

 

 

 

 

Description

Parameter

Notes

 

 

 

Serial output voltage swing

600 < Vout < 1300 mV

Centered at 1.32V

 

 

 

 

Figure 18 provides the data output valid eye diagram relative to the bit cell time.

941 ps

Vout (mv)

800 ps

Figure 18. Transmit eye diagram

9.6.3Differential PECL input

The serial PECL input signal voltage characteristics are provided in Table 27.

Table 27:

Differential PECL input characteristics

 

 

 

 

Description

Parameter

Notes

 

 

 

Serial input voltage swing

200 < Vin < 1.300 mV

AC coupled

 

 

 

 

Figure 19 provides the data valid eye diagram for typical and minimum requirements to recover data at the specified interface error rate. The inputs are AC coupled on the drive.

Vin (mv)

941 ps

659 ps

376 ps

Typical

Minimum

Figure 19. Receive eye diagram

Savvio 15K.1 FC Product Manual, Rev. B

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Seagate ST936751FC, ST973451FC manual Differential Pecl output, Differential Pecl input