I'm having an issue with the flashing circuit on the LM3914. I'm using the alarm flasher circuit from the datasheet:http://www.ti.com/lit/ds/symlink/lm3914.pdf. It's designed for 5V, but I'm using it at 9V. It does work, kinda. It flashes at the high voltage reference, but above that it goes solid again. It also "latches," if the input voltage gets turned down, it keeps flashing until the voltage drops substantially. For reference, the low voltage is at 1.25V, the high is at 2.5V. Once it starts flashing, it doesn't stop until the input drops to 1.7V. I'm not entirely sure how the circuit works either. From what I can tell, C3 charges through R5. When LED10 turns on, that pin goes low and C3 discharges. After that, not really sure what is happening, other than it causes pin 6/7 on the 3914 to oscillate.
I want to remove the latch and get it to flash at any voltage above 2.5V, no matter what. Ideas? Datasheet says you can turn off the current sources by pulling positive on the reference pin with 100 uA or gating the input with a transistor.
I want to remove the latch and get it to flash at any voltage above 2.5V, no matter what. Ideas? Datasheet says you can turn off the current sources by pulling positive on the reference pin with 100 uA or gating the input with a transistor.
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