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Programmable voltage output differential (vod) – Altera Stratix GX Transceiver User Manual

Page 21

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Altera Corporation

2–3

January 2005

Stratix GX Transceiver User Guide

Stratix GX Analog Description

Programmable Voltage Output Differential (V

OD

)

Stratix GX transceivers let you customize the differential output voltage
(V

OD

) to handle different length, backplane, and receiver requirements

(see

Figure 2–3

). You can select the V

OD

(differential) from a range of 400

to 1,600 mV, as shown in

Table 2–1

.

Figure 2–3. V

OD

(Differential) Signal Level

Table 2–1

shows the differential output voltage (V

OD

) setting per current

level for each of the on-chip transmitter programmable termination
values.

Single-Ended Waveform

Differential Waveform

(VOD (Differential) = 2 x VOD (single-ended))

Positive Channel (p) = V

OH

Negative Channel (n) = V

OL

Ground

V

OD

V

OD

V

OD

p

n = 0 V

V

CM

Table 2–1. Programmable V

O D

(Differential)

100

(mV)

120

(mV)

150

(mV)

400

480

600

800

960

1,200

1,000

1,200

1,500

1,200

1,440

1,400

1,600