Test Circuitry (TTL-to-ECL)
DS100306-7
Note 15: R = 50Ω termination resistive load. When an input or output is being monitored by a scope, R is supplied by the scope’s 50Ω input resistance. When
T
T
an input or output is not being monitored, an external 50Ω resistance must be applied to serve as R .
T
Note 16: TTL and ECL force signals are brought to the DUT via 50Ω coax lines.
Note 17: V
is decoupled to ground with 0.1 µF, V is decoupled to ground with 0.01 µF and V is connected to ground.
CC
TTL
EE
FIGURE 1. TTL-to-ECL AC Test Circuit
Switching Waveforms (TTL-to-ECL)
DS100306-9
FIGURE 2. TTL to ECL Transition—Propagation Delay and Transition Times
7
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