
Application Information (Continued)
INVERTER EXTERNAL CAPACITORS
As discussed in the +5 LDO Regulator External Capacitors
section, the output resistance and ripple voltage are depen-
dent on the capacitance and ESR values of the external
capacitors. A minimum of 1F capacitor with good tolerance
over temperature for capacitance and ESR values. The ca-
pacitance value can be increased without limit while still
maintain high low ESR value. 2.2F capacitors are recom-
mended for the two external capacitors, C
2 and C5 of the
inverter.
10110026
FIGURE 5. ESR Curve for C
OUT = 4.7F
10110027
FIGURE 6. ESR Curve for C
OUT =10F
LM2685
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