ELECTRONICS: Linear Technology Corp.’s LTC2470 and LTC2472 are a pair of 16-bit delta sigma ADCs that integrate a high accuracy reference in tiny 3 mm x 3 mm DFN and 12-lead MSOP packages. The device’s integrated 1.25V reference offers 2ppm/ºC drift performance and 0.1 percent initial accuracy for precise measurements in space-constrained applications. Both ADCs provide guaranteed 16-bit no missing code resolution and selectable 250sps or 1ksps output rate. The LTC2470 and LTC2472 are ideal for system and environmental monitoring and data acquisition systems requiring fast output rates.
Operating from a single 2.7 to 5.5V supply, these ADCs are designed to measure single-ended (LTC2470) or differential (LTC2472) sensors via an SPI serial interface. With its internal 1.25V reference, the LTC2470 can measure a single-ended input between 0V and 1.25V, while the LTC2472 is capable of measuring a differential input up to ±1.25V.
The versatile LTC2470/LTC2472 achieve excellent 16-bit dc performance of 2LSB (typ) integral nonlinearity error at 250sps, 3µVRMS transition noise and 0.25 percent gain error (max). An internal oscillator eliminates the need for external components to perform conversions.
The LTC2470/LTC2472 draw 3.5 mA supply current during a conversion. After each conversion, the ADC enters a nap mode, reducing supply current to less than 1.5 mA (max). Supply current can be further reduced by placing the converter in sleep mode to achieve less than 2 µA(max). The LTC2470/LTC2472 also incorporate a proprietary input sampling network that reduces the dynamic input current to less than 50 nA, making a wide range of external input protection and filter circuits possible.
The LTC2470 and LTC2472 are each offered in small 12-pin 3 mm x 3 mm DFN and MSOP packages. They are available today in both commercial and industrial temperature grade versions. Pricing for the LTC2470 & LTC2472 begin at $1.70 each in 1,000-piece quantities.
- Edited by Liz Taurasi