Maxim MAX1492 Manuals

MAXIM MAX148/MAX149 +2.7V to +5.25V Low-Power 8-Channel Serial 10-Bit ADCs handbook

The MAX148/MAX149 10-bit data-acquisition systems combine an 8-channel multiplexer, high-bandwidth track/hold, and serial interface with high conversion speed and low power consumption. They operate from a single +2.7V to +5.25V supply, and sample to 133ksps. Both devices’ analog inputs are software configurable for unipolar/bipolar and single-ended/differential operation. The 4-wire serial interface connects directly to SPI™/ QSPI™ and MICROWIRE™ devices without external logic. A serial-strobe output allows direct connection to TMS320-family digital signal processors. The MAX148/ MAX149 use either the internal clock or an external serial- interface clock to perform successive-approximation analog-to-digital conversions. The MAX149 has an internal 2.5V reference, while the MAX148 requires an external reference. Both parts have a reference-buffer amplifier with a ±1.5% voltage- adjustment range. These devices provide a hard-wired SHDN pin and a software-selectable power-down, and can be pro- grammed to automatically shut down at the end of a con- version. Accessing the serial interface automatically powers up the MAX148/MAX149, and the quick turn-on time allows them to be shut down between all conver- sions. This technique can cut supply current to under 60µA at reduced sampling rates. The MAX148/MAX149 are available in a 20-pin DIP and a 20-pin SSOP. For 4-channel versions of these devices, see the MAX1248/MAX1249 data sheet.