CA-IS1306AM25W

CA - IS1306x series devices are a family of precision isolated sigma-delta (Σ-Δ) modulators optimized for shunt resistor-based current sensing or other small-signal measurement applications. An input current sense amplifier monitors the current through the shunt (sense) resistor, and the sigma-delta modulator converts the analog input into a high-frequency digital bitstream of 1s and 0s. The analog input side (high side) and digital output side (low side) are separated by a proprietary silicon dioxide (SiO₂) capacitive isolation barrier, which provides up to 5kV RMS galvanic isolation per UL1577 certification, with an isolation driver transmitting the modulator output across this barrier. In systems with different voltage domains, this isolation technique is commonly used to protect the low-voltage side from the high-voltage side in the event of any fault. These devices also feature common-mode transient immunity of up to 150kV/μs, enabling robust bitstream transmission in noisy environments. The ultra-low input voltage range (±250mV) of the CA-IS1306x devices allows the use of small sense resistors to reduce power consumption, while the extremely low 0.2% gain error ensures measurement accuracy. The series also incorporates fail-safe outputs to support high-safety system designs. CA-IS1306x devices are specified for clock inputs from 5MHz to 21MHz. The internal sigma-delta modulator combined with an external digital decimation sinc3 filter achieves 85dB SNR at 78.1Ksps. The CA-IS1306x series is specified over an operating temperature range of -40°C to +125°C and is available in an 8-pin SOIC wide-body package.

Applications

• Industrial motor control and drives
• Isolated power supplies
• Process signal isolation

Key features

• Full-scale detection voltage range: ±250mV
• Unencoded bitstream output
• Ultra-low input offset voltage and gain error
• Input offset voltage ±100μV (max) at 25°C
• Gain error ±0.2% (max) at 25°C
• Low drift
• Input offset temperature coefficient ±3.5μV/°C (max)
• Gain drift ±40ppm/°C (max)
• Excellent AC performance
• SNR: 85dB (typical)
• THD: -93dB (typical)
• 16-bit resolution, no missing codes
• Wide supply operating range
• High-side and low-side supply range: 3.3V to 5.5V
• Robust isolation barrier
• Long lifetime: >40 years
• Isolation rating up to 5000VRMS
• Typical CMTI ±150kV/μs
• Fault diagnostic function for enhanced system safety
• Wide operating temperature range: -40°C to 125°C
• Safety regulatory certifications
• VDE 0884-17 isolation certification
• UL certification per UL1577
• IEC 61010-1:2010+A1 certification