The AD7401A1 is a second-order sigma-delta (Σ-Δ) modulator with a 16-pin SOIC operating in the temperature range −40°C to +125°C. Converts analog input signals into high-speed 1-bit data streams with digital on chip isolation based on analog Devices, Inc. iCoupler technology.
Functional block diagram
Application program
• Ac motor control
• Shunt current monitoring
• Data acquisition system
• Analog to digital converter and optical isolator replacement
The AD7401A operates from a 5v power supply and accepts a pseudo-differential input signal of ±250 mV(±320 mV full scale). Analog inputs are continuously sampled by an analog modulator, eliminating the need for external sampling and holding circuits. Input information is contained in the output stream at a density of up to 20 MHz at data rates. The original information can be reconstructed with appropriate digital filters.
Digital output timed gauge load circuit
The device contains an on-chip reference. Serial I/O can use either a 5v or 3.3V power supply (VDD2). The serial port is digitally isolated. The combination of high-speed CMOS with Analog Devices, Inc. 's iCoupler technology means that on-chip isolation offers excellent performance characteristics over alternatives such as optocoupler devices.
Data Timing
