The AD7405 is a high performance, second-order, Σ-Δ modulatorthat converts an analog input signal into a high speed, single-bitLVDS data stream, with on-chip digital isolation based onAnalog Devices, Inc., iCoupler^® technology. The AD7405operates from a 5 V (VDD1) power supply and accepts adifferential input signal of ±250 mV (±320 mV full-scale). Thedifferential input is ideally suited to shunt voltage monitoring inhigh voltage applications where galvanic isolation is required.

The analog input is continuously sampled by a high performanceanalog modulator, and converted to a ones density digital outputstream with a data rate of up to 20 MHz. The originalinformation can be reconstructed with an appropriate digitalfilter to achieve 88 dB signal to noise ratio (SNR) at 78.1 kSPS.The LVDS input/output can use a 5 V or a 3.3 V supply (VDD2).

The LVDS interface is digitally isolated. The LVDS interfacetechnology, combined with monolithic transformer technology,means the on-chip isolation provides outstanding performancecharacteristics, superior to alternatives such as optocouplerdevices. The AD7405 device is offered in a 16-lead, wide-bodySOIC package and has an operating temperature range of −40°Cto +125°C.

Applications

• Shunt current monitoring
• AC motor controls
• Power and solar inverters
• Wind turbine inverters
• Data acquisition systems
• Analog-to-digital and opto-isolator replacements

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.