Precision digital timing controller circuit (CC4013, CC440, CC4060, G1555)
Shown for the precision digital timing control circuit. The controller consists of crystal oscillator circuit, a divider, counting circuit, monostable flip-flops.
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Crystal oscillator circuit consists of 14 serial binary counter / divider, watch crystal (32768Hz), C1, C2 and so on. Oscillator signal after 214 division (Q14) output from the pin, inverted by the IC2, then after the double-D flip-flop CC4013 (IC3) divided by two to give the signal of 1Hz, the signal is applied to the CP end of IC4, as a clock control signal.IC4 is a 12-bit serial binary counter / divider CC4040, when the CP signal at a frequency of 1Hz, 11 output terminals Q4 ~ Q9, Q12 ~ Q14 respectively output 2 seconds, 4 seconds, 8 seconds, 16 seconds, 32 seconds , 64 seconds, 128 seconds, 256 seconds, 512 seconds, 1024 seconds, 2048 seconds pulse (high step). Based on the timing required by sub-line single-pole 11 throw switch K corresponding step level timing leads the way. Added to the amplifier BG1, BG2, by the amplified signal coupled to IC5 feet, 555 feet low because occurs set, pin output high relay J pull, turn the corresponding control load, so that the work load.The timing controller work program is: Wait 2N (N = 2 ~ 11) seconds after the relay only pull, turn the work. After that, because C3 is charged through R4, when the voltage on C3 charge to make potential reaches 6 feet 2 / 3VDD, the 555 reset occurs, the output pin low relay J release, the corresponding load off, stop working. At the same time, a signal from the K leads through diode D after clearing Cr added to the end of IC4 (12 feet), the timer is cleared, that is, in 555 output is high, the load is turned on at the same time, and from 0 to start counting , the timing of the next round. Thus achieving different general timer.Timing of the timing controller can be from 2 to 2,048 seconds, minutes, 11-grade, high timing accuracy, than the average over the timer.
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