Si8931/32 Data Sheet
Isolated Amplifier for Voltage Measurement
KEY FEATURES The Si8931/32 is a galvanically isolated analog amplifier optimized for voltage sensing. Its 2.5
V input range is ideal for isolated voltage sensing applications. The output is a differential analog signal (Si8931) or single-ended signal (Si8932) that is proportional to the input voltage.
The Si8931/32 provides excellent linearity with low offset and gain drift to ensure that accuracy
is maintained over the entire operating temperature range. Exceptionally high common-mode
transient immunity means that the Si8931/32 delivers accurate measurements even in the presence of high-power switching as is found in motor drive systems and inverters.
The Si8931/32 isolated voltage sensing amplifier utilizes Silicon Labs’ proprietary isolation technology. It supports up to 5.0 kVrms withstand voltage per UL1577. This technology enables
higher performance, reduced variation with temperature and age, tighter part-to-part matching,
and longer lifetimes compared to other isolation technologies.
Applications:
• Industrial, HEV and renewable energy inverters
• AC, Brushless, and DC motor controls and drives
• Variable speed motor control in consumer white goods
• Isolated switch mode and UPS power supplies
• Automotive BMS and charging
• General industrial data acquisition and sensor interface • 0 to 2.5 V nominal input voltage
• Low signal delay: 1 µs
• Typical input offset: 0.2 mV
• Typical gain error: ±0.1%
• Excellent drift specifications
• 0.75 µV/°C offset drift
• 6 ppm/°C typical gain drift …
