24-bit, 10 mW, 130 dB SNR, 64 ksps Δ-Σ ADC

September 17, 2014 // By Graham Prophet
Maxim Integrated has posted details of its MAX11270, an ADC with an integrated programmable gain amplifier that it presents as having the highest SNR and lowest power in its class

The MAX11270 is a 24-bit delta-sigma ADC that achieves 130 dB SNR while dissipating 10 mW. Sample rates up to 64 ksamples/sec allow both precision DC and AC measurements. Integral nonlinearity is guaranteed to 4 ppm maximum. The THD is -122 dB. The MAX11270 connects via an SPI-compatible serial interface and occupies a 24-pin TSSOP package.

It specifies a 6.5 nV/√Hz noise programmable gain amplifier with gain settings between 1x to 128x. Optional buffers are also included to provide isolation of the signal inputs from the switched capacitor sampling network. This allows the MAX11270 to be used with high-impedance sources without compromising available dynamic range.

The MAX11270 operates from a single 2.7V to 3.6V analogue supply, or split ±1.8V analogue supplies, allowing the analogue input to be sampled below ground. The digital supply range is 2.0V to 3.6V, allowing communication with 2.5V, 3V, or 3.3V logic. Other parameters include;

High resolution for instrumentation applications;

130dB SNR at 1.9 sps

112dB SNR at 1000 sps

20.4-bit noise-free resolution at 1.9 sps

17.4-Bit noise-free resolution at 1000 sps

There is also a programmable SINC filter as the basis of a flexible high-performance filter architecture.

Use the part, Maxim suggests, in ATE, high-precision portable sensors, medical equipment and instrumentation in general.

Maxim Integrated; www.maximintegrated.com/en/products/analog/data-converters/analog-to-digital-converters/MAX11270.html