DESCRIPTION

· The Si8941/46/47 are galvanically isolated delta-sigma modulators that output a digital signal proportional to the input voltage level. Ideal for measuring voltage across a current shunt resistor or isolating sensors from control systems, they ensure accurate system current measurement with low noise, low error, and high precision. The modulators can be clocked from an on-board oscillator (Si8946/47) or an external clock (Si8941), with outputs typically filtered by an MCU or FPGA. Utilizing Skyworks' proprietary isolation technology, they support up to 5.0 kVRMS withstand voltage per UL1577, offering higher performance, reduced temperature and age variation, tighter part-to-part matching, and longer lifetimes compared to other isolation technologies. Automotive-grade options are available, ensuring robustness and low defectivity for automotive applications.

FEATURES

· Low voltage differential input options: ±62.5 mV and ±250 mV.
· Modulator clock options: External clock up to 25 MHz (Si8941), 10 MHz internal clock (Si8946), 20 MHz internal clock (Si8947).
· Typical input offset: ±50 µV.
· Typical gain error: ±0.05%.
· Excellent drift specifications: ±0.5 µV/°C typical offset drift, ±4 ppm/°C typical gain drift.
· Typical 14-bit (ENOB) precision.
· High common-mode transient immunity: 75 kV/µs.
· Typical SNR: 90 dB.
· Typical THD: –97 dB.
· Automotive-grade OPNs available with AEC-Q100 qualification, AIAG-compliant PPAP documentation support, and IMDS and CAMDS listing support.
· Compact packages: 8-pin wide body stretched SOIC, 8-pin narrow body SOIC.
· Operating temperature range: –40 to 125 °C.
· Safety approvals: UL 1577 recognized (up to 5000 kVRMS for 1 minute), CSA certification conformity (62368-1 reinforced insulation), VDE certification conformity (60747-17 reinforced insulation pending), CQC certification approval (GB4943.1).

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 on-board chargers, battery management systems, and charging stations.