Adjustable DC/DC Buck Module LM2596S I/P 3-40V O/P 1,5-35V 3A (Requires 1,5V Differential) See also BMT ADJ DC/DC MODULE 3A 1,5-35VAdjustable DC/DC Buck Module Overview This DC-DC module uses the step-down switching regulator LM2596S to provide a stable power supply for the users. The output...
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Use an old laptop charger (18-19 V) to power one of these set for a float voltage e.g. 13.6 for lead acid.
Dual Coil Version DC/DC Constanat Output Auto Buck/Boost Module with HI Value Caps. Stabilised Output. XL6009 Chip. Ideal For VehicleS. I/P 5-32V. O/P 1,25-32V Adjustable- 4A Max.Constanat Output Auto Buck/Boost Module Overview Auto start voltage will be pulled down to 7V or less, and engine...
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Put that on the output to get constant 12 V.
You will have a nice on-line UPS with zero transfer time and several days runtime.