AD8420 Wide Supply Range, Micropower, Rail-to-Rail Instrumentation Amplifier

The AD8420 is a low cost, micropower, wide supply range, instrumentation amplifier with a rail-to-rail output and a novel architecture that allows for extremely flexible design. It is optimized to amplify small differential voltages in the presence of large common-mode signals.

The AD8420 is based on an indirect current feedback architecture that gives it an excellent input common-mode range. Unlike conventional instrumentation amplifiers, the AD8420 can easily amplify signals at or even slightly below ground without requiring dual supplies. The AD8420 has rail-to-rail output, and the output voltage swing is completely independent of the input common-mode voltage.

Single-supply operation, micropower current consumption, and rail-to-rail output swing make the AD8420 ideal for battery-powered applications. Its rail-to-rail output stage maximizes dynamic range when operating from low supply voltages. Dual-supply operation (±15 V) and low power consumption make the AD8420 ideal for a wide variety of applications in medical or industrial instrumentation.

The AD8420 is available in an 8-lead MSOP package. Performance is specified over the full temperature range of −40°C to +85°C, and the part is operational from −40°C to +125°C

APPLICATIONS

Bridge amplifiers
Pressure Measurement
Medical instrumentation
Portable data acquisition
Multichannel systems

Features and Benefits

Maximum supply current:
90 μA

Minimum CMRR: 100 dB

Drives heavy capacitive loads:
~700 pF

Rail-to-rail output

Input voltage range goes below ground

Gain set with 2 external resistors
Can achieve low gain drift at any gain

Very wide power supply range
Single supply: 2.7 V to 36 V
Dual supply: ±2.7 V to ±18 V

Bandwidth (G = 100): 2.5 kHz

Input voltage noise: 55 nV/√Hz

See data sheet for additional features

Amplifiers

Instrumentation Amplifiers

Building Technology

Building Control and Automation

Aerospace and Defense

Solutions

SPICE Models

AD8420 SPICE Macro Model .CIR

Reference Designs

Data Sheets

Document	note
AD8420: Wide Supply Range, Micropower, Rail-to-Rail Instrumentation Amplifier Data Sheet (Rev. A)	PDF 249 kB

User Guides

Document	note
UG-513: Evaluating the AD8237 Micropower, Zero Drift, True Rail-to-Rail Instrumentation Amplifier and the AD8420 Wide Supply Range, Micropower, Rail-to-Rail Instrumentation Amplifier	PDF 221 kB

Technical Books

Document	note

Order Information

Part Number	Package	Packing Qty	Temp Range	Price 100-499	Price 1000+	RoHS
AD8420ARMZ Production	8 ld MSOP	OTH 50	-40 to 85C	1.11	0.89	Y
AD8420ARMZ-R7 Production	8 ld MSOP	REEL 1000	-40 to 85C	1.11	0.89	Y
AD8420ARMZ-RL Production	8 ld MSOP	REEL 3000	-40 to 85C	1.11	0.89	Y