Tektronix 071-0590-00 Amplitude and Baseline Offset, Output Setup Rules vs. Termination Impedance

Reference

Amplitude and Baseline Offset

The rules governing the setup of clock and data amplitude and baseline offset are as follows:

RULE 1: When terminated by 50 Ohms to ground, the amplitude adjustment range of clock and data outputs is 0 to 2 V peak-to-peak . However, the absolute voltage of the pulse top cannot exceed +2.0 VDC, that is:

Vamplitude p-p + Voffset ≤ 2.0 VDC

RULE 2: When left unterminated (termination impedance > 2 kΩ) the amplitude adjustment range of clock and data outputs is 0 to 4 V peak-to-peakwith a pulse top limit of +4.0 VDC, that is:

Vamplitude p-p + Voffset ≤ 4.0 VDC

RULE 3: Displayed amplitude and baseline offset are calibrated for a termination of 50 Ohms to ground. Any variation of termination impedance or voltage will cause actual amplitude and offset to differ from the values shown in the Generator display.

These rules are summarized in the table below.

Table 3-2. Output Setup Rules vs. Termination Impedance

	Termination	Amplitude Limit	Pulse Top	Actual	Actual Baseline Offset
		(V p-p)	Limit (VDC)	Amplitude	(VDC)
50	Ω to ground	0 - 2	+2.0	as displayed	as displayed
50	Ω to -2 VDC	0 - 2	+2.0	as displayed	displayed value - 1.0 V
AC (50 Ω to AC)		0 - 2	+2.0	as displayed	unspecified
Open Circuit		0 - 4	+4.0	2 x displayed	as displayed

Note: With PECL option installed, the pulse top limits are increased to 2.8 (50Ω) and +5.6 (open circuit).

3-14 GB1400 User Manual