Multichannel, True-Differential, Serial, 14-Bit ADCs

The MAX1146–MAX1149 low-power, 14-bit, multichannel, analog-to-digital converters (ADCs) feature an internal track/hold (T/H), voltage reference, and clock. The MAX1146/MAX1148 operate from a single +4.75V to +5.25V supply, and the MAX1147/MAX1149 operate from a single +2.7V to +3.6V supply. All analog inputs are software configurable for unipolar/bipolar and single-ended/differential operation.

The 4-wire serial interface connects directly to SPI™/QSPI™/MICROWIRE™ devices without external logic. The serial strobe output (SSTRB) allows convenient connection to digital signal processors. The MAX1146–MAX1149 use an internal clock or an external serial-interface clock to perform successive-approximation analog-to-digital conversions.

The MAX1146/MAX1148 include an internal +4.096V reference, while the MAX1147/MAX1149 include an internal +2.500V reference. All devices accept an external reference from 1.5V to VDD.

The MAX1146–MAX1149 provide a hardware shutdown and two software power-down modes. Using the software power-down modes allows the devices to be powered down between conversions. When powered down, accessing the serial interface automatically powers up the devices. The quick turn-on time allows power-down between all conversions. This technique reduces supply current to under 120µA for quick turn-on. The MAX1146–MAX1149 are available in a 20-pin TSSOP package.

Applications

* Battery-Powered Instruments * Data Acquisition * Medical Instruments * Portable Data Logging * Process Control

* 8-Channel Single-Ended or 4-Channel Differential Inputs (MAX1148/MAX1149)

* 4-Channel Single-Ended or 2-Channel Differential Inputs (MAX1146/MAX1147)

* Internal Multiplexer and T/H

* Single-Supply Operation

* 4.75V to 5.25V Supply (MAX1146/MAX1148)

* 2.7V to 3.6V Supply (MAX1147/MAX1149)

* Internal Reference

* +4.096V (MAX1146/MAX1148)

* +2.500V (MAX1147/MAX1149)

* 116ksps Sampling Rate

* Low Power

* 1.1mA (116ksps)

* 120µA (10ksps)

* 12µA (1ksps)

* 300nA (Power-Down Mode)

* SPI-/QSPI-/MICROWIRE Compatible

* 20-Pin TSSOP