GN2014A Datasheet, PDF (14/18 Pages) Gennum Corporation – XFP Tx Signal Conditioner with VCSEL Driver

To decrease the cross point to the 25% level, the CPA polarity (pin 10:CPAPol) must be
set LOW, and the CPA voltage (pin 12:CPA) increased to 3.1V. This results in the output
waveform illustrated in Figure 3-6.
Crosspoint
75%
50%
25%
0ps
60ps
120ps
180ps
Time(s)
Figure 3-6: GN2014A Output Signal when CPA Polarity control input is set
LOW, CPA = 3.1V
The cross point can be set to an intermediate level between 50% and 25% by setting the
CPA to a voltage between 0.8V and 3.1V.
Note: When the CPA Control function is not used, connect CPA (pin 12: CPA) to V_CC
using a 200KΩ resistor. The CPAPol pin (pin 10: CPAPol) may be left open.
GN2014A XFP Tx Signal Conditioner with VCSEL Driver
Data Sheet
39260 - 8
May 2010
14 of 18
Proprietary & Confidential