GENERAL DESCRIPTION

The ADuM7703 is a high performance, second-order, Σ-Δ analog-

to-digital converter (ADC) with an integrated low dropout (LDO) regulator that converts an analog input signal into a high speed, single-bit data stream with on-chip digital isolation

based on Analog Devices, Inc., iCoupler® technology. The

device operates from a 4.5 V to 20 V power supply range (VDD1)

and accepts a pseudo differential input signal of ±250 mV

(±320 mV full-scale). The pseudo differential input is ideally suited to shunt voltage monitoring in high voltage applications where galvanic isolation is required.

The analog input is continuously sampled by a high performance analog modulator and converted to a ones density digital output stream with a data rate of up to 21 MHz. The original information

can be reconstructed with an appropriate sinc3 digital filter to

achieve an 86 dB signal-to-noise ratio (SNR) at 78.1 kSPS with a

256 decimation rate and a 20 MHz master clock. The serial

input and output operates from a 5 V or a 3.3 V supply (VDD2).

The serial interface is digitally isolated. High speed complementary metal-oxide semiconductor (CMOS) technology, combined with monolithic transformer technology, results in the on-chip isolation

providing outstanding performance characteristics, superior to alternatives such as optocoupler devices. The ADuM7703 device is available in a 16-lead, wide-body SOIC with an operating

temperature range of −40°C to +125°C and an 8-lead, wide-body

SOIC with an operating temperature range of −40°C to +105°C.