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8 Second to 8.5 Minute Low Frequency Clock (Intervalometer for Time-Lapse Photography)

This circuit example highlights the use of the LTC6991 in a intervalometer for time lapse photography. In this example the LTC6991 is configured as a self-resetting circuit and generates a fixed time pulse from 8s to 64s. The LTC6991 is part of the TimerBlox family of versatile silicon timing devices with a programmable period range of 1.024ms to 9.54 hours (29.1μHz to 977Hz). This device is specifically intended for long duration timing events. A single resistor programs the LTC6991’s internal master oscillator frequency. Normally the LTC6991 oscillates with a 50% duty cycle but the reset function can truncate the pulse (reducing the duty cycle).

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