Datasheet Si8935/36/37 (Silicon Labs)

Si8935/36/37 Data Sheet
Delta-Sigma Modulator for Voltage Measurement
KEY FEATURES
The Si8935/36/37 is a galvanically isolated delta-sigma modulator optimized for voltage sens- ing. Its 2.5 V input range is ideal for isolated voltage sensing applications. The Si8935/36/37 • 0 to 2.5 V nominal input voltage provides excellent linearity with low offset and gain drift to ensure that accuracy is maintained • Modulator clock options over the entire operating temperature range. Exceptionally high common-mode transient im- • External clock up to 25 MHz munity means that the Si8935/36/37 delivers accurate measurements even in the presence of (Si8935) high-power switching as is found in motor drive systems and inverters. • 10 MHz internal clock (Si8936) The output of the Si8935/36/37 comes from a second-order, delta-sigma modulator. The modu- • 20 MHz internal clock (Si8937) lator can be clocked either from an onboard oscillator (Si8936/37) or from an external clock • Typical input offset: ±0.6 mV (Si8935). The output is typically digitally filtered by a MCU or FPGA in the system. • Typical gain error: ±0.1% • Excellent drift specifications The Si8935/36/37 isolated delta-sigma modulator utilizes Silicon Labs’ proprietary isolation • 1 µV/°C typical offset drift 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, • 30 ppm/°C typical gain drift and longer lifetimes compared to other isolation technologies. • Typical nonlinearity: 0.02% • Typical SNR: 81 dB
Applications:
• High common-mode transient • Industrial, HEV and renewable energy inverters immunity: 75 kV/µs • AC, Brushless, and DC motor controls and drives • Compact packages • Variable speed motor control in consumer white goods • 8-pin wide body stretched SOIC • Isolated switch mode and UPS power supplies • 8-pin narrow body SOIC • –40 to 125 °C • Automotive BMS and charging • General industrial data acquisition and sensor interface
Safety Approvals (Pending):
• UL 1577 recognized • Up to 5000 Vrms for 1 minute • • CSA component notice 5A approval • IEC 60950-1 (reinforced insulation) • VDE certification conformity • VDE0884 Part 10 (basic/reinforced insulation) • CQC certification approval • GB4943.1 Si8935, Si8936, Si8937 VDDA VDDB VIN CLK ACLK DSM NC ADAT
Transmitter Receiver
GNDA CMOS Isolation GNDB
silabs.com
| Building a more connected world. Preliminary Rev. 0.1 This information applies to a product under development. Its characteristics and specifications are subject to change without notice. Document Outline 1. Ordering Guide 2. System Overview 2.1 Modulator 3. Voltage Sense Application 4. Electrical Specifications 4.1 Regulatory Information 5. Pin Descriptions 5.1 Si8935/36/37 Pin Descriptions 6. Packaging 6.1 Package Outline: 8-Pin Wide Body Stretched SOIC 6.2 Package Outline: 8-Pin Narrow Body SOIC 6.3 Land Pattern: 8-Pin Wide Body Stretched SOIC 6.4 Land Pattern: 8-Pin Narrow Body SOIC 6.5 Top Marking: 8-Pin Wide Body Stretched SOIC 6.6 Top Marking: 8-Pin Narrow Body SOIC 7. Document Revision History