Analog Devices Inc./Maxim Integrated MAX492CSA

Overview

MAX492CSA from Maxim Integrated is a dual, micropower, single-supply rail-to-rail operational amplifier optimized for low-voltage battery-powered systems. It operates from +2.7V to +6V, delivers 500kHz gain-bandwidth, draws ≤150µA per amplifier, achieves ±200µV input offset voltage (typ), and drives 1kΩ loads with rail-to-rail output swing. It is used in portable instrumentation signal conditioning where precision, ultra-low power, and wide dynamic range are critical.

For engineers reviewing the MAX492CSA datasheet, MAX492CSA pinout, MAX492CSA application, or MAX492CSA equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed application use cases, and two rigorously cross-checked alternative parts - all grounded in the official MAX492/MAX494/MAX495 datasheet Rev 2 (9/96).

Technical Context

The MAX492CSA integrates two independent op amps sharing a common VCC and VEE supply, each featuring complementary NPN/PNP input stages enabling true rail-to-rail common-mode input range (VEE − 0.25V to VCC + 0.25V) and rail-to-rail output swing (within 50mV of rails at 100kΩ). Its folded-cascode architecture supports unity-gain stability while maintaining 25nV/√Hz input voltage noise and >108dB large-signal voltage gain.

It uses internal back-to-back diode protection (1.7kΩ series resistors) on inputs to limit differential overvoltage damage, and its output stage is designed to drive ≥1nF capacitive loads without external isolation - a key differentiator versus standard CMOS rail-to-rail op amps. No phase reversal occurs even when inputs exceed supply rails.

Key Specifications

Pinout & Package

MAX492CSA is housed in an 8-pin SO (Small Outline) package, industry-standard pinout matching dual op amp footprints. Pin functions are electrically identical to the plastic DIP version (MAX492CPA), enabling drop-in replacement in existing layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual rail-to-rail op amp applications.

Compared with TLV2462IDR and AD8602ARMZ, the MAX492CSA uniquely balances micropower operation (≤150µA), true rail-to-rail input beyond supplies, and robust overvoltage protection - making it irreplaceable in long-life, low-voltage, fault-tolerant analog front-ends.

Availability

MAX492CSA is available at Aetrix Electronics and suitable for portable equipment, battery-powered instruments, and data acquisition systems requiring stable component supply and long-term obsolescence management.

Supply support for MAX492CSA 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) is a fabless semiconductor company specializing in high-performance analog and mixed-signal ICs for power, interface, sensing, and timing applications.

The MAX492/MAX494/MAX495 family was engineered specifically for ultra-low-power, single-supply, rail-to-rail signal conditioning in portable and battery-constrained systems - prioritizing DC accuracy, supply current, and input/output voltage range over raw speed.

FAQ

Is MAX492CSA recommended for new designs?

No. Maxim explicitly states "Not Recommended for New Designs" due to discontinuation of the legacy wafer process. However, MAX492CSA remains available through authorized distributors and Aetrix Electronics for legacy system support, repair, and continuity programs. Engineers designing new products should evaluate modern alternatives like the MAX44267 or AD8602, but MAX492CSA is fully supported for existing designs requiring exact form-fit-function replacement.

What is the operating temperature range of MAX492CSA?

The MAX492CSA is rated for 0°C to +70°C ambient operation, as indicated by the 'C' suffix in its ordering code. This commercial-grade temperature range is validated across all electrical specifications in the datasheet's DC and AC characterization tables for TA = 0°C to +70°C, including supply current (175µA max), offset voltage (±650µV max), and CMRR (72dB min).

Does MAX492CSA support single-supply operation below 3V?

Yes. The MAX492CSA is fully specified down to +2.7V single supply, with all key parameters - including rail-to-rail input common-mode range (VEE − 0.20V to VCC + 0.20V), output swing (within 75mV of rails), and 500kHz gain-bandwidth - guaranteed at VCC = 2.7V. This enables reliable operation from partially discharged Li-ion cells or regulated 2.8V rails.

Can MAX492CSA drive capacitive loads without oscillation?

Yes. The MAX492CSA is characterized to drive >1nF capacitive loads stably, with documented performance up to 10,000pF when combined with a 47Ω isolation resistor (Figure 9b). Even without isolation, it sustains stability with 1000pF pure capacitance (Figure 6) - a result of its internally compensated output stage optimized for low-quiescent-current operation.

Is offset voltage adjustable on MAX492CSA?

No. Offset null pins (NULL1/NULL2) are present only on the single MAX495 variant (8-pin SO/µMAX). The dual MAX492CSA lacks dedicated null terminals; its input offset voltage is trimmed at wafer test and fixed at ±200µV (typ) / ±500µV (max) over temperature. External trimming requires discrete circuitry and is not supported by the MAX492CSA pinout or internal architecture.