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TOPIC 3: ASTABLE MODE
PERIOD, T
The total period:
T = TH + TL
= 0.693 (RA + 2RB) C
FREQUENCY, F
The astable circuit’s frequency of oscillation:
F = 1/T
= (1.44) / [ (RA+ 2RB)C ]
MARK TO SPACE RATIO
Timing resistors and capacitors in the circuit control when
the time output is high (the mark time) and when the time
output is low (the space time).
Mark to space ratio = Time High (TH)/Time Low (TL)
= TH : TL
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