Analog Devices Inc. AMP04EPZ

Overview

AMP04EPZ from Analog Devices is a precision single-supply instrumentation amplifier optimized for low-power, high-accuracy signal conditioning in battery-powered and industrial sensor interfaces. It delivers 150 µV max input offset voltage, 700 µA max supply current, gain range of 1–1000 set by one external resistor, and rail-to-rail-compatible output swing within 1 V of the positive rail - enabling direct interfacing with 5 V ADCs in strain gage, RTD, and thermocouple measurement systems.

For engineers reviewing the AMP04EPZ datasheet, AMP04EPZ pinout, AMP04EPZ application, or AMP04EPZ equivalent, this page provides verified technical context, validated pin functions, real-world application cards for sensor front-ends, and two confirmed alternative parts with documented functional and packaging differences - all grounded in Analog Devices' official AMP04 specification documents and package drawings.

Technical Context

The AMP04EPZ employs a proprietary three-op-amp topology with laser-trimmed thin-film resistors to achieve 0.005% gain nonlinearity and 30 ppm/°C gain tempco. Its input stage supports true zero-volt common-mode operation on single +5 V supplies, unlike conventional instrumentation amplifiers that require ≥0.4 V headroom.

It features accessible internal feedback nodes (Pin 6 and Pin 8) for external noise filtering, a dedicated REF pin for output-level shifting in unipolar systems, and dual gain-set resistor terminals (Pins 1 & 8) enabling driven-shield configurations for high-impedance transducer cabling - all confirmed in the functional block diagram and application circuits.

Key Specifications

Pinout & Package

AMP04EPZ is housed in an 8-lead plastic DIP (P suffix) package with through-hole mounting and 0.3-inch body width. Pin spacing follows standard 0.1-inch grid; thermal resistance θJA = 103°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar instrumentation amplifier applications.

Compared with AD620ARZ and INA128UA, AMP04EPZ uniquely combines single-supply zero-in operation, 700 µA supply current, and REF-pin-based output offset control - making it the only option among the three qualified for battery-powered, ground-referenced sensor nodes requiring field recalibration.

Availability

AMP04EPZ is available at Aetrix Electronics and suitable for precision sensor front-ends, portable medical instrumentation, and industrial 4–20 mA loop interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AMP04EPZ 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Wilmington, MA, serving industrial, automotive, communications, and healthcare markets since 1965.

The AMP04EPZ belongs to Analog Devices' precision instrumentation amplifier product line, engineered specifically for low-power, single-supply sensor signal conditioning in harsh environments - emphasizing zero-input capability, laser-trimmed accuracy, and robust noise rejection.

FAQ

What is the maximum supply voltage for AMP04EPZ?

The absolute maximum supply voltage for AMP04EPZ is ±18 V, as specified in the Absolute Maximum Ratings table. For reliable operation, Analog Devices recommends staying within the specified operating range of +5 V to ±15 V. Exceeding ±18 V risks permanent damage to the internal ESD protection structures and thin-film resistors. The AMP04EPZ maintains full performance across its entire rated supply range, including stable gain accuracy and CMRR at both extremes.

Can AMP04EPZ operate with a single +3.3 V supply?

No - AMP04EPZ is not characterized or guaranteed for operation below +5 V. Its input common-mode range extends to ground and its output swings within 1 V of the positive rail, but internal biasing and amplifier headroom require minimum +5 V for specified offset, gain, and bandwidth performance. Using +3.3 V may result in degraded CMRR, increased offset drift, or failure to meet the 150 µV max input offset voltage specification. For 3.3 V systems, consider the AD8221 or AD8421 families.

How do I calculate RGAIN for a target gain of 250 on AMP04EPZ?

Use the gain equation G = 100 kΩ / RGAIN. For G = 250, RGAIN = 100 kΩ / 250 = 400 Ω. Select a 402 Ω ±0.1% metal-film resistor for best accuracy - this yields G = 248.8, well within the 0.75% gain equation error limit at G ≤ 100. Place RGAIN between Pins 1 and 8 with shortest possible trace length and guard it from noise sources to preserve CMRR. Do not use potentiometers unless actively trimmed and sealed, as their tempco degrades overall system stability.

Does AMP04EPZ support AC-coupled inputs?

Yes - AMP04EPZ supports AC-coupled inputs when the REF pin is biased to a stable DC level (e.g., mid-supply via resistor divider). Its input stage does not require DC return paths to V+ or V–, allowing capacitive coupling for isolation or high-pass filtering. However, ensure the REF voltage remains low-impedance (<100 Ω) to avoid CMRR degradation, and verify that input coupling capacitor value provides adequate low-frequency response for your signal bandwidth - e.g., 10 µF for 0.1 Hz cutoff with 150 kΩ effective input impedance.

What is the purpose of the dual RGAIN pins (1 and 8) on AMP04EPZ?

Pins 1 and 8 are internally connected to opposite ends of the 100 kΩ internal feedback resistor network and provide symmetrical access points for the external RGAIN resistor. This dual-terminal configuration enables driven-shield applications: connecting a unity-gain buffer to either pin replicates the input common-mode voltage onto a cable shield, reducing capacitive leakage and EMI pickup in high-impedance sensor connections. It also improves layout symmetry for optimal CMRR - especially critical in PCBs with asymmetric routing or ground plane discontinuities near the AMP04EPZ.