Linear Technology's LTC2440 is a high-speed 24-bit no latency ΔΣ ADC with 5 ppm INL and 5 µV offset. It uses proprietary ΔΣ architecture enabling variable speed and resolution with no latency. Ten speed / resolution combinations (6.9 Hz / 200 nVR MS to 3.5 kHz / 25 µVRMS) are programmed through a simple serial interface. Alternatively, by tying a single pin HIGH or LOW, a fast (880 Hz / 2 µVRMS) or ultra low noise (6.9 Hz, 200 nVRMS, 50 / 60 Hz rejection) speed/resolution combination can be easily selected. The accuracy (offset, full-scale, linearity, drift) and power dissipation are independent of the speed selected. Since there is no latency, a speed/resolution change may be made between conversions with no degradation in performance.

Following each conversion cycle, the LTC2440 automatically enters a low-power sleep state. Power dissipation may be reduced by increasing the duration of this sleep state. For example, running at the 3.5 kHz conversion speed but reading data at a 100 Hz rate draws 240 µA average current (1.1 mW) while reading data at a 7 Hz output rate draws only 25 µA (125 µW).The LTC2440 communicates through a flexible 3-wire or 4-wire digital interface that is compatible with the LTC2410 and is available in a narrow 16-lead SSOP package.