GENERAL DESCRIPTION

The AD74001 is a second-order, sigma-delta (Σ-Δ) modulator

that converts an analog input signal to a high speed, 1-bit data

stream with on-chip digital isolation based on Analog Devices, Inc. iCoupler® technology. The AD7400 operates from a 5 V

power supply and accepts a differential input signal of ±200 mV

(±320 mV full scale). The analog input is continuously sampled

by the analog modulator, eliminating the need for external sample-and-hold circuitry. The input information is contained

in the output stream as a density of ones with a data rate of 10 MHz. The original information can be reconstructed with an

appropriate digital filter. The serial I/O can use a 5 V or a 3 V

supply (VDD2).

The serial interface is digitally isolated. High speed CMOS,

combined with monolithic air core transformer technology, means the on-chip isolation provides outstanding performance

characteristics superior to alternatives such as optocoupler devices. The part contains an on-chip reference. The AD7400 is

offered in a 16-lead SOIC and has an operating temperature

range of −40°C to +105°C. An external clock version, AD7401, is also available.

FEATURES

10 MHz clock rate Second-order modulator

16 bits no missing codes

±2 LSB INL typical at 16 bits 3.5 μV/°C maximum offset drift

On-board digital isolator On-board reference Low power operation: 18 mA maximum at 5.25 V

−40°C to +105°C operating range

16-lead SOIC package

Safety and regulatory approvals UL recognition 5000 V rms for 1 minute per UL 1577 CSA Component Acceptance Notice #5A VDE Certificate of Conformity DIN V VDE V 0884-10 (VDE V 0884-10):2006-12 VIORM = 891 V peak

APPLICATIONS

AC motor controls

Data acquisition systems

A/D + opto-isolator replacements