Analog Devices Inc. EVAL-CN0390-EB1Z

Overview

EVAL-CN0390-EB1Z from Analog Devices is an evaluation board for a composite-amplifier-enhanced Howland current source (CAEHCS), designed to deliver ±500 mA output with sub-0.03% full-scale dc accuracy and 100 ns settling time. It integrates ADA4870 (high-drive) and ADA4898-2 (precision) amplifiers, 2 Ω sense resistor R0, and matched gain networks (R1/R2 = R3/R4 = 10) for voltage-controlled current sourcing in precision test equipment.

For engineers reviewing the EVAL-CN0390-EB1Z datasheet, EVAL-CN0390-EB1Z pinout, EVAL-CN0390-EB1Z application, or EVAL-CN0390-EB1Z equivalent, this board enables rapid validation of high-accuracy, fast-settling VCCS topologies-particularly where dc offset, thermal drift, and slew-rate-limited current step response are critical selection criteria.

Technical Context

The EVAL-CN0390-EB1Z implements a two-stage composite amplifier architecture: ADA4870 provides high-current drive (1.2 A limit, 2500 V/µs slew rate), while ADA4898-2 delivers precision error correction (20 µV VOS, 0.1 µA IB, 63 MHz bandwidth). The topology isolates dc accuracy from ac performance constraints.

It realizes a true voltage-to-current conversion per i_L = (u_in+ − u_in−) / (k·R₀), where k = R₁/R₂ = R₃/R₄ = 10 and R₀ = 2 Ω. Load independence is maintained up to 10 Ω, with measured output current offset of 0.2 mA and 100 ns 0.1% settling to ±500 mA steps.

Key Specifications

Availability

EVAL-CN0390-EB1Z is available at Aetrix Electronics and suitable for automated test equipment, electrochemical instrumentation, precision sensor excitation, and semiconductor characterization systems requiring stable component supply and validated reference design implementation.

Supply support for EVAL-CN0390-EB1Z includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, communications, automotive, and healthcare markets.

EVAL-CN0390-EB1Z belongs to Analog Devices' Circuit Note (CN) evaluation platform series, specifically developed to demonstrate validated, application-optimized analog subsystems-here, high-fidelity voltage-controlled current sources for metrology and test engineering.

FAQ

What is the primary function of the EVAL-CN0390-EB1Z evaluation board?

The EVAL-CN0390-EB1Z evaluation board implements a composite-amplifier-enhanced Howland current source (CAEHCS) that converts a differential input voltage into a highly accurate, fast-settling output current. It demonstrates the EVAL-CN0390-EB1Z's capability to deliver ±500 mA with 0.2 mA dc offset and 100 ns settling time-enabling engineers to validate VCCS performance before integrating into production test or instrumentation systems.

Which amplifiers are used on the EVAL-CN0390-EB1Z, and what roles do they serve?

The EVAL-CN0390-EB1Z uses ADA4870 as the high-drive output stage (1.2 A limit, 2500 V/µs slew rate) and ADA4898-2 as the precision error-correction amplifier (20 µV VOS, 63 MHz bandwidth). This dual-amplifier topology decouples dc accuracy from ac performance-ensuring EVAL-CN0390-EB1Z achieves both sub-0.03% current accuracy and nanosecond-scale transient response.

Does the EVAL-CN0390-EB1Z support bidirectional current output?

Yes, the EVAL-CN0390-EB1Z supports true bidirectional current sourcing and sinking up to ±500 mA. Its differential input architecture and symmetric power supply routing (±10 V to ±20 V) allow linear operation across the full range, making EVAL-CN0390-EB1Z suitable for applications like impedance spectroscopy and active load testing where polarity reversal is required.

What is the role of the 2 Ω sense resistor (R0) on the EVAL-CN0390-EB1Z?

The 2 Ω sense resistor (R0) sets the transconductance gain of the EVAL-CN0390-EB1Z: i_L = (u_in+ − u_in−) / (k·R₀), where k = 10. It directly determines output current scaling and dominates thermal dissipation-measured at 8.3 W at ±20 V/500 mA. R0's low TC metal film construction minimizes drift, ensuring EVAL-CN0390-EB1Z maintains accuracy over temperature.

Can the EVAL-CN0390-EB1Z be used without modification for 10 Ω load applications?

Yes, the EVAL-CN0390-EB1Z is characterized and validated for loads up to 10 Ω, with minimal degradation in dc accuracy (<0.05% added relative error) and bandwidth (8 MHz). Its CAEHCS topology inherently maintains load independence-confirmed by test data showing only 0.2 mA total offset at 10 Ω-making EVAL-CN0390-EB1Z directly applicable to real-world transducer and actuator interfaces.