ISOSD61L

ADCs/DACs - Special Purpose Overview

The ISOSD61L is a galvanically isolated second-order Sigma-Delta modulator from STMicroelectronics, utilizing embedded transformer coupling technology. It converts analog input signals within a ±320 mV full-scale range into a high-speed 1-bit digital data stream at up to 25 Msps. The device features LVDS digital I/O and provides 16-bit resolution with no missing codes when paired with a digital filter. Key electrical parameters include an 86 dB typical SNR, -83 dB THD, and 13-bit ENOB. It operates on a 3 V to 5.5 V low-voltage supply (VDD) and a 4.5 V to 5.5 V isolation-side supply (VDDISO), supporting an extended industrial temperature range of –40°C to +125°C.

ADCs/DACs - Special Purpose Feature Summary

• Galvanic isolation via embedded transformer coupling with 30 kV/µs common-mode transient immunity.
• LVDS interface for high-speed digital output with up to 25 MHz external clock input.
• 16-bit resolution with no missing codes, 86 dB SNR, and ±320 mV differential input range.
• Certified safety approvals including UL1577 and IEC 60747-17 in SO-16 wide package.

ADCs/DACs - Special Purpose Applications

• Current or voltage sensing in industrial motor control
• Solar inverters
• Uninterruptible Power Supplies (UPS)
• Electric vehicle chargers
• Telecom and server power supplies

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific ordering suffix 'LTR' corresponds to the Tape and Reel packing format as defined in the manufacturer's ordering information table. Confirm that the application design accommodates the required VDDISO supply voltage range of 4.5 V to 5.5 V, which differs from the standard VDD range. Ensure compliance with the recommended footprint dimensions and clearance/creepage distances specified for the SO-16W package to maintain isolation integrity.

ADCs/DACs - Special Purpose Selection Notes

Select the ISOSD61L over the single-ended ISOSD61 variant when LVDS signaling is required for noise immunity and high-speed data transmission. Ensure the host system can provide a stable 4.5 V to 5.5 V supply for the isolation side (VDDISO). Designers must implement appropriate digital filtering, such as a SINC3 filter, to reconstruct the 16-bit data from the 1-bit modulator stream. Verify that the analog input signal remains within the ±200 mV recommended operating condition to avoid saturation.

ADCs/DACs - Special Purpose Part Context

The ISOSD61L belongs to the ISOSD61 family of isolated Sigma-Delta modulators. It shares the same core modulator architecture and isolation barrier as the ISOSD61 but utilizes Low Voltage Differential Signaling (LVDS) for its digital interface instead of single-ended TTL/CMOS. This differentiation allows for robust communication in electrically noisy environments while maintaining the same 16-bit resolution and isolation characteristics.

ADCs/DACs - Special Purpose Replacement Considerations

The ISOSD61L is functionally compatible with the ISOSD61 regarding analog performance and isolation, differing only in the digital interface type (LVDS vs. Single-Ended). For packaging alternatives, the ISOSD61TR serves as the tape-and-reel version of the single-ended model, while ISOSD61LTR is the direct tape-and-reel equivalent of the ISOSD61L.