AD7405 16-Bit, Isolated Sigma-Delta Modulator, LVDS Interface

The AD7405 is a high performance, second-order, Σ-Δ modulator that converts an analog input signal into a high speed, single-bit LVDS data stream, with on-chip digital isolation based on Analog Devices, Inc., iCoupler® technology. The AD7405 operates from a 5 V (VDD1) power supply and accepts a differential input signal of ±250 mV (±320 mV full-scale). The 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 20 MHz. The original information can be reconstructed with an appropriate digital filter 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 interface technology, combined with monolithic transformer technology, means the on-chip isolation provides outstanding performance characteristics, superior to alternatives such as optocoupler devices. The AD7405 device is offered in a 16-lead, wide-body SOIC package and has an operating temperature range of −40°C to +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

Features and Benefits

5 MHz to 20 MHz external clock input rate
16 bits, no missing codes
Signal-to-noise ratio (SNR): 88 dB typical
Effective number of bits (ENOB): 14.2 bits typical
Typical offset drift vs. temperature: 1.6 μV/°C typical
LVDS interface
On-board digital isolator

On-board reference
Full-scale analog input range: ±320 mV
−40°C to + 125°C operating range
High common-mode transient immunity: >25 kV/μs
16-lead, wide-body SOIC, with increased creepage package
See data sheet for additional features

Analog to Digital Converters

Isolated A/D Converters

IBIS Models

AD7405 IBIS Model .IBS

Data Sheets

Document	note
AD7405: 16-Bit, Isolated Sigma-Delta Modulator, LVDS Interface Data Sheet (Rev. A)	PDF 360.44 K

Application Notes

Document	note
AN-1377: Gain and Offset Temperature Drift Compensation for the AD7403/AD7405 (Rev. A)	PDF 91.67 K

User Guides

Document	note
UG-690: Evaluating the AD7405 16-Bit Isolated Sigma-Delta ADC	PDF 1.22 M

Order Information

Part Number	Package	Packing Qty	Temp Range	Price 100-499	Price 1000+	RoHS
AD7405BRIZ Production	16 ld SOIC (increased Creepage)	OTH 37	-40 to 125C	3.95	3.35	Y
AD7405BRIZ-RL Production	16 ld SOIC (increased Creepage)	REEL 1000	-40 to 125C	0	3.35	Y
AD7405BRIZ-RL7 Production	16 ld SOIC (increased Creepage)	REEL 400	-40 to 125C	0	3.35	Y