12-Bit, I2C SAR ADC from Linear Technology

The input channels are software selectable for unipolar or bipolar ranges. Operating from a single 5V supply, the LTC2309 draws just 1.5mW at a 1ksps throughput rate and only 35uW in shutdown mode. Packaged in a tiny 4mm x 4mm QFN-24 with internal reference, the LTC2309 is a great fit for portable instrumentation and space-constrained designs using I2C.

The LTC2309 achieves excellent DC specifications when measuring unipolar or bipolar input signals, including ±1LSB INL and DNL, ±6LSB (max) zero-scale error and ±6LSB (max) full-scale error. The LTC2309 also excels when digitizing AC input signals, measuring 73dB SINAD and -88dB THD at 1kHz.

The LTC2309 allows I2C data transfers up to 100kHz in standard mode and 400kHz in fast mode. The ADC includes two address select pins that may be tied low, high or left floating, thus providing nine unique I2C addresses. This is ideal for applications that require measurements of more than eight input channels, as designers can easily communicate with multiple LTC2309 devices.