Test Circuitry (TTL-to-ECL)
DS100295-7
=
50Ω termination. When an input or output is being monitored by a scope, R is supplied by the scope’s 50Ω resistance. When an input or output is
t
Note 16:
R
t
not being monitored, an external 50Ω resistance must be applied to serve as R .
t
Note 17: TTL and ECL force signals are brought to the DUT via 50Ω coax lines.
Note 18:
V
is decoupled to ground with 0.1 µF to ground, V is decoupled to ground with 0.01 µF and V is connected to ground.
EE CC
TTL
Note 19: For ECL input pins, the equivelent force/sense circuitry is optional.
FIGURE 1. TTL-to-ECL AC Test Circuit
Switching Waveforms (TTL-to-ECL)
DS100295-9
FIGURE 2. TTL to ECL Transition — Propagation Delay and Transition Times
7
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