Sneak circuit is a latent circuit path or condition that causes undesired function to occur at some certain conditions. A step-down resonant switched capacitor (RSC) converter was used as an example to analyze the converter operating process with sneak circuit state. The sneak circuit characteristics and the sneak circuit operating conditions were derived by law of energy conservation. When sneak circuits appear

the output voltage doesnt keep constant

but relates to converter parameters or operating conditions. The converter shows the undesired behaviors under sneak circuit state

which have been verified by experimental results.