The MIC4681 SuperSwitcher™ is an easy-to-use step-down (buck) voltage-mode switching regulator. The 200kHz MIC4681 achieves over 1A of continuous output current over a 4V to 30V input range in an 8-lead SOPpackage . The MIC4681 features a high 2.1A minimum current limit, making the device ideal for pulsed current applications such as GSM and TDMA cell phone battery chargers and power supplies. The MIC4681 sustains an output of 4.2V/2A within a typical GSM charging environment. The MIC4681 has an input voltage range of 4V to 30V, with excellent line, load, and transient response. The regulator performs cycle-by-cycle current limiting and thermal shutdown for protection under fault conditions. In shutdown mode, the regulator draws less than 6µA of standby current. The MIC4681 SuperSwitcher™ regulator requires a minimum number of external components and can operate using a standard series of inductors and capacitors. Frequency compensation is provided internally for fast transient response and ease of use. The MIC4681 is available in the 8-lead SOP with a –40°C to +125°C junction temperature range.