Long-time-timer

31,731

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When used as a stand-alone device, the ZN1034E from Ferranti can provide timed intervals ranging from 1 second to 19 days, although the RC time constant is only 220 seconds. The ZN1034E includes an internal voltage regulator, an oscillator, and a 12-stage binary counter. The total delay time provided by the counter is 4095 times the oscillator period. The control logic times out after 4095 cycles of the oscillator and delivers high and low output pulses at pins 2 and 3. The output at pin 3 is normally high and decreases at the end of the timed interval. The complementary output at pin 2 is normally low and becomes high at the end of the timed interval. The timing period is initiated by momentarily grounding pin 1. The timing resistor R7 consists of two resistors, R1 and R2, in series. Because R1 has a fixed value of 100 kΩ, the total range of R7 is from 100 kΩ to 1.1 MΩ.

The ZN1034E timer circuit is designed for applications requiring precise timing intervals over an extensive range. The internal voltage regulator ensures stable operation by maintaining a consistent voltage supply, which is crucial for accurate timing. The oscillator generates clock pulses that drive the 12-stage binary counter, allowing for a maximum timing duration that can be calculated as 4095 times the oscillator period. This provides flexibility in applications where varying timing intervals are needed.

The outputs at pins 2 and 3 serve distinct functions. Pin 3 provides a high output during the timing period, transitioning to low at the conclusion of the set interval, which can be utilized to trigger subsequent actions in a circuit. Conversely, pin 2 operates in a complementary manner, remaining low throughout the timing period and switching high at the end, making it suitable for signaling purposes or as an enable signal for other components.

The initiation of the timing cycle is accomplished by grounding pin 1, which activates the timing sequence. The timing resistor R7, composed of R1 and R2 in series, allows for fine-tuning of the timing interval. With R1 fixed at 100 kΩ, the variable resistor R2 can be adjusted to achieve a total resistance range from 100 kΩ to 1.1 MΩ. This adjustability is critical for tailoring the timing characteristics to meet specific application requirements, whether for short delays or extended timing sequences.

Overall, the ZN1034E is a versatile and reliable timing device suitable for a wide range of electronic applications, providing both high precision and flexibility in timing control.When used as a stand-alone device, ZN1034E from Ferranti can provide timed intervals ranging from 1 second to 19 days, although the rc time constant is only 220 seconds. The ZN1034E includes an internal voltage regulator, an oscillator, and a 12-stage binary counter. The total delay time provided by the counter is 4095 times the oscillator period. The control logic times-out after 4095 cyCles of the oscillator, and delivers high and low output pulses at pins 2 and 3.

The output at pin 3 is normally high and decreases at the end of the timed interval. The complementary output at pin 2 is normally low and becomes high at tbe end of the timed interval. The timing period is initiated by momentarily grounding pin 1. Timing resistor R 7 consists of two resistors, R1 and R2, in series. Because R1 has a fixed value of 100 KO, the total range of R7 is 100 K to 1.1 MO. 🔗 External reference