Sigma-Delta ADCs cascadable up to 32 simultaneous channels

The MAX11040K/MAX11060 are 24-/16-bit, 4-channel, simultaneous-sampling, sigma-delta analog-to-digital converters (ADCs). The devices allow simultaneous sampling of as many as 32 channels using a built-in cascade feature to synchronize as many as eight devices.

The serial interface of the devices allows reading data from all the cascaded devices using a single command. Four modulators simultaneously convert each fully differential analog input with a programmable data output rate ranging from 0.25ksps to 64ksps.

The devices achieve 106dB SNR at 16ksps and 117dB SNR at 1ksps (MAX11040K). The devices operate from a single +3V supply. The differential analog input range is ±2.2V when using the internal reference; an external reference is optional. Each input is overvoltage protected up to ±6V without damage. The devices use an internal crystal oscillator or an external source for clock.

The devices are compatible with SPI, QSPI™, MICROWIRE®, and DSP-compatible 4-wire serial interfaces. An on-board interface logic allows one serial interface (with a single chip select) to control up to eight cascaded devices or 32 simultaneous sampling analog input channels.

The devices are ideally suited for power-management systems. Each channel includes an adjustable sampling phase enabling internal compensation for phase shift due to external dividers, transformers, or filters at the inputs. The output data rate is adjustable with a 0.065% resolution (at 16ksps or below) to track the varying frequency of a periodic input. An active-low SYNC input allows periodic alignment of the conversion timing of multiple devices with a remote timing source.

The devices are available in a 38-pin TSSOP package specified over the -40°C to +105°C industrial temperature range.