Zero-Drift Op Amps Bring Greater Precision To Wearable Products
With an input-offset voltage of 5 µV at 25°C an 30-nV/°C temperature stability, STMicroelectronics’ TSZ121 family of zero-drift op amps will meet the front-end signal-conditioning or low-side current-measurement needs in Internet of Things (IoT) or wearable-device applications. According to the company, their precision guarantees accuracy without trimming. In addition, the op amps’ ultra-low temperature drift prevents system-performance degradation at higher temperatures without requiring self-calibration. All devices operate from 1.8 to 5.5 V, with quiescent current below 40 µA at 5 V and very low input bias current. Gain-bandwidth product equals 400 kHz. The single-channel TSZ121 (in SC70-5 or SOT-25L packaging) is pin- and package-compatible with comparable devices from other manufacturers. The dual-channel TSZ122 comes in MiniSO-8 and SO-8 packages, as well as an optional 2- by 2-mm DFN8. The quad-channel TSZ124 features TSSOP-14 and 3- by 3-mm QFN16 packaging options. Specific applications include temperature sensors, wellness and fitness monitors, and automotive controls.