The MAX1246 has an internal 2.5V reference, while the MAX1247 requires an external reference. Both parts have a reference-buffer amplifier with a 1.5% voltageadjustment range. These devices provide a hard-wired SHDN pin and a software-selectable power-down, and can be programmed to automatically shut down at the end of a conversion. Accessing the serial interface automatically powers up the MAX1246/MAX1247, and the quick turn-on time allows them to be shut down between all conversions. This technique can cut supply current to under 60A at reduced sampling rates. The MAX1246/MAX1247 are available in a 16-pin DIP and a small QSOP that occupies the same board area as an 8-pin SO.