3.13 6.3V Heater PSU
The E1T tube heaters operate at 6.3V 300mA, therefore this switched mode down convertor will
provide about 2A. The heater PSU can be switched on by the SAM3X8C via the buffer/level
convertor IC10. The convertor has a soft start feature which is configured to take roughly 10
seconds to increase the output voltage from 0V to 6.3V. This substantially reduces the inrush
current to the cold heaters, hopefully prolonging their life.
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Summary of Contents for An E1T Timepiece
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