Analog Devices Inc./Maxim Integrated MAX4275AGESA+

Overview

MAX4275AGESA+ from Maxim Integrated is a single-channel, noninverting fixed-gain amplifier with internal V_CC/2 biasing, housed in a 5-pin SOT23 package. It delivers +5V/V gain with 0.1% accuracy, operates from +2.5V to +5.5V supply, consumes only 300µA, and features rail-to-rail output swing driving 1kΩ loads - ideal for low-power single-supply signal conditioning in portable instrumentation.

For engineers reviewing the MAX4275AGESA+ datasheet, MAX4275AGESA+ pinout, MAX4275AGESA+ application, or MAX4275AGESA+ equivalent, key selection criteria include its factory-trimmed gain accuracy, ±17V input fault protection, 23MHz GBW product at high gains, capacitive-load stability up to 470pF, and integrated V_CC/2 bias eliminating external resistors in AC-coupled front-ends.

Technical Context

The MAX4275AGESA+ integrates a rail-to-rail output op-amp core with laser-trimmed internal feedback resistors (R_F/R_G) and dual 150kΩ resistors forming a V_CC/2 bias network at the noninverting input. Its compensation is optimized for +5V/V gain, delivering 23MHz GBW and 330kHz –3dB bandwidth.

Input protection includes back-to-back SCRs and diode clamps with current limiting (≤3.5mA at ±17V overvoltage), while the inverting input remains directly connected to R_G, constraining its voltage range to the supply rails - unlike the biased noninverting input which is fixed at V_CC/2.

Key Specifications

Pinout & Package

MAX4275AGESA+ uses a 5-pin SOT23 package (JEDEC MO-178AA), with exposed pad for thermal enhancement. Pin 1 is marked by a dot; pin numbering follows standard SOT23 orientation (counterclockwise from mark).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-gain amplifier applications.

Compared with MAX4175EUK+T, MAX4275AGESA+ extends operational temperature to +125°C and improves thermal reliability for under-hood or enclosed industrial use; versus AD8275ARMZ, it offers lower power, built-in biasing, and true noninverting topology - making it superior for compact, battery-efficient, single-supply sensor interfaces.

Availability

MAX4275AGESA+ is available at Aetrix Electronics and suitable for portable instrumentation, smart-card readers, low-side current-sense circuits, and photodiode preamplifiers requiring stable component supply, guaranteed gain accuracy, and extended-temperature performance.

Supply support for MAX4275AGESA+ 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

Maxim Integrated (now part of Analog Devices) designs high-performance analog and mixed-signal ICs for power, sensing, communications, and timing applications.

The MAX4275AGESA+ belongs to the GainAmp™ fixed-gain amplifier product line, engineered to replace discrete op-amp-plus-resistor configurations with factory-trimmed accuracy, reduced footprint, and enhanced robustness in space-constrained, low-power systems.

FAQ

What is the exact gain configuration and tolerance of the MAX4275AGESA+?

The MAX4275AGESA+ is a noninverting fixed-gain amplifier with a nominal gain of +5V/V. Its gain accuracy is specified at 0.1% due to factory laser trimming of internal R_F/R_G resistors. This tolerance holds across the full operating temperature range (–40°C to +125°C) and supply voltage range (+2.5V to +5.5V), ensuring consistent signal scaling without calibration in production systems.

Does the MAX4275AGESA+ require external biasing components for single-supply operation?

No. The MAX4275AGESA+ integrates dual 150kΩ resistors that form an internal V_CC/2 bias network at the IN+ pin. This eliminates the need for external resistors or capacitors to establish a mid-supply reference, simplifying design and reducing PCB area - especially valuable in AC-coupled sensor front-ends where the MAX4275AGESA+ is commonly deployed.

What is the maximum capacitive load the MAX4275AGESA+ can drive without oscillation?

The MAX4275AGESA+ is stable with capacitive loads up to 470pF when driving directly from the output pin, per Maxim's Electrical Characteristics table. This specification applies with no series isolation resistor and RL = 100kΩ. For loads exceeding 470pF, a small series resistor (e.g., 10–100Ω) may be added to restore phase margin, as documented in the Capacitive-Load Stability section of the MAX4275AGESA+ datasheet.

How does the ±17V input fault protection work on the MAX4275AGESA+?

The MAX4275AGESA+ employs back-to-back SCR structures at both IN+ and IN– pins, combined with diode clamps to V_CC and V_EE. When either input exceeds the supply rails by up to ±17V, the SCRs conduct limited current (≤3.5mA) to protect the internal op-amp core. This architecture prevents latch-up and allows safe recovery after transient overvoltage - a key advantage over standard op-amps in noisy or uncontrolled signal environments.

Can the MAX4275AGESA+ be used in dual-supply configurations?

Yes. Although optimized for single-supply use with its internal V_CC/2 bias, the MAX4275AGESA+ supports dual supplies from ±1.25V to ±2.75V. In such configurations, V_EE is connected to the negative rail (e.g., –2.5V), and the internal bias network still references the midpoint between V_CC and V_EE. However, for pure dual-supply DC-coupled applications, the MAX4174/MAX4274 variants (without V_CC/2 bias) are typically preferred to avoid unnecessary bias current paths.