The ISO7421 and ISO7421M provide galvanic isolation up to 2.5 kVrms for 1 minute per UL. These digital isolators have two isolated channels. Each isolation channel has a logic input and output buffer separated by a silicon dioxide (SiO2) insulation barrier. Used in conjunction with isolated power supplies, these devices prevent noise currents on a data bus or other circuit from entering the local ground and interfering with or damaging sensitive circuitry.