Circuits comprising: a first capacitor(C1); a first switch(S1) having a first side coupled to a VIN and a second side coupled to a first side of C1; a second switch(S2) having a first side coupled to the second side of S1; a third switch(S3) having a first side coupled to a second side of S2 and a second side coupled to a second side of C1; a fourth switch(S4) having a first side coupled to a second side of S3 and a second side coupled to a VSUPPLY, wherein: in a first state, S1 and S3 are off, and S2 and S4 are on; in a second state, S1 and S3 are on, and S2 and S4 are off; and at least one of a control of S1, a control of S2, a control of S3, and a control of S4 is coupled to a time-varying-slew-rate signal.