Search Results for "R-78"

The enable pin has two functions: Below 2.6V, the converter is OFF (the output power stage is switched off, but the converter oscillator is still running). Below 1.6V, the converter is in ultra-low power mode ( 20µA shutdown mode)

It is recommended that the R-78 series of switching converters is used with a minimum load of 6mA to guarantee that the output is stable under all operating conditions.

Type is not critical. Actually, a lower quality, relatively high ESR capacitor on the input is actually an advantage as its internal resistance helps damp down any switch-on surge oscillations.
A combination of tantalum or electrolytic in parallel with an MLCC on the input or output combines the advantages of both types (high ESR to reduce ringing, low ESR to filter noise).

The R-78 costs more than a linear regulator because it is intelligent. It may look similar to a three-pin linear regulator, but it is far more efficient and inside is a controller chip that protects the converter against overload, over temperature and short circuits. This makes it very robust and hard-to-kill.
Even if the converter itself costs more, the savings that can be made in the primary power supply (because it needs less output current), assembly (because there is no fiddly heatsink, screw, nut and thermal paste to worry about) and inventory (one part rather than 7 parts with the linear regulator + heatsink + mounting + input and output capacitors) mean that the overall power supply cost can be lower with the R-78 than with the ""cheaper"" linear regulator.