Test Circuitry
Note:
• VCC, VCCA = +2V, VEE = −2.5V
• L1, L2 and L3 = equal length 50Ω impedance lines
• RT = 50Ω terminator internal to scope
• Decoupling 0.1 µF from GND to VCCand VEE
• All unused outputs are loaded with 50Ω to GND
• CL = Fixture and stray capacitance ≤ 3 pF
FIGURE 1. AC Test Circuit
Note:
• For shift right mode pulse generator connected to S0 is moved to S1.
• Pulse generator connected to S1 has a LOW frequency 99% duty cycle, which allows occasional parallel load.
• The feedback path from output to input should be as short as possible.
FIGURE 2. Shift Frequency Test Circuit (Shift Left)
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