The CG635 has several clock outputs. The front-panel Q and -Q outputs provide complementary square waves at standard logic levels (ECL, PECL, LVDS or +7 dBm).
The square wave amplitude may also be set from 0.2 V to 1.0 V, with an offset between -2 V and +5 V. These outputs operate from DC to 2.05 GHz, have transition times of 80 ps, a source impedance of 50 Ω, and are intended to drive 50 Ω loads.
Output levels double when these outputs are unterminated.
The front-panel CMOS output provides square waves at standard logic levels. The output may also be set to any amplitude from 0.5 V to 6.0 V. The CMOS output has transition times of less than 1 ns and operates up to 250 MHz.
It has a 50 Ω source impedance and is intended to drive high impedance loads at the end of any length of 50 Ω coax cable.
A rear-panel RJ-45 connector provides differential square wave clocks on twisted pairs at RS-485 levels (up to 105 MHz) and LVDS levels (up to 2.05 GHz).
This output also provides ±5 VDC power for optional line receivers (CG640 to CG649).
The clock outputs have 100 Ω source impedances and are intended to drive shielded CAT-6 cable with 100 Ω terminations.
The differential clocks may be used directly by the target system, or with optional line receivers that provide complementary logic outputs on SMA connectors.
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