Analog Devices Inc./Maxim Integrated MAX4521ESE+T

Overview

MAX4521ESE+T from Maxim Integrated is a quad, low-voltage, normally closed (NC) SPST analog switch IC designed for rail-to-rail signal routing in precision analog and mixed-signal systems. It features 100Ω max on-resistance, 4Ω max channel-to-channel R_ON matching, <1µW quiescent power, ±2V to ±6V dual or +2V to +12V single supply operation, and operates across –40°C to +85°C. It is used in battery-powered data acquisition front-ends where low leakage and signal integrity are critical.

For engineers reviewing the MAX4521ESE+T datasheet, MAX4521ESE+T pinout, MAX4521ESE+T application, or MAX4521ESE+T equivalent, key selection criteria include NC configuration, guaranteed R_ON flatness (≤12Ω), sub-1nA off-leakage at +25°C, TTL/CMOS-compatible logic thresholds, and ESD robustness (>2kV per Method 3015.7).

Technical Context

The MAX4521ESE+T implements four independent CMOS transmission gates with complementary N- and P-channel MOSFETs driven by level-shifted logic, enabling true rail-to-rail analog signal handling from V– to V+. Its internal logic translators accept TTL/CMOS inputs at ±5V or +5V supplies and generate full-swing gate drives referenced to V+ and V–.

Each switch exhibits matched on-resistance (ΔR_ON ≤ 4Ω) and flat on-resistance (R_FLAT(ON) ≤ 12Ω) over the full signal range, ensuring minimal gain error and crosstalk in multiplexed sensor or audio paths. Off-isolation exceeds –90dB at 100kHz, and charge injection is limited to 1–5pC - critical for sample-and-hold and precision ADC interface applications.

Key Specifications

Pinout & Package

MAX4521ESE+T is housed in a 16-pin narrow SO (SOIC-N) package (S16-2), 3.9mm × 9.9mm body, 1.27mm pitch, with exposed pad connected to V+ for thermal and electrical stability.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar analog switch applications.

Compared with MAX4522ESE+T and ADG1412BRUZ, the MAX4521ESE+T uniquely delivers NC default behavior with sub-1nA +25°C leakage and 100Ω R_ON in a cost-optimized SO package - making it optimal for fail-safe, low-power, precision analog multiplexing.

Availability

MAX4521ESE+T is available at Aetrix Electronics and suitable for portable data acquisition, avionics signal routing, and battery-powered test equipment requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for MAX4521ESE+T 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 semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The MAX4521 series belongs to Maxim's precision analog switch product line, engineered for low-leakage, rail-to-rail signal routing in battery-constrained and high-reliability systems where NC default state and ESD resilience are mandatory.

FAQ

What is the default switch state of MAX4521ESE+T?

The MAX4521ESE+T features four normally closed (NC) SPST analog switches. When all IN1–IN4 inputs are logic low (≤0.8V), the corresponding NC–COM paths are conductive. Applying logic high (≥2.4V) opens each switch. This NC default ensures signal continuity during power-up, reset, or controller failure - a critical safety feature in medical and avionics signal paths. The MAX4521ESE+T does not support break-before-make timing.

Does MAX4521ESE+T support single-supply operation?

Yes, MAX4521ESE+T operates from a single +2V to +12V supply by connecting V– to GND. It is fully specified down to +2.7V, delivering 600Ω max R_ON at +2.7V and 100Ω max at +5V. Logic thresholds remain TTL/CMOS-compatible across this range, and off-leakage stays below 10nA at +85°C. No external level shifters are needed - the internal logic translators automatically adapt to the applied V+.

What is the maximum analog signal range supported by MAX4521ESE+T?

The MAX4521ESE+T supports rail-to-rail analog signals from V– to V+. With ±5V supplies, the usable range is ±4.5V; with +5V single supply (V– = GND), it is 0V to +4.5V. Internal ESD diodes clamp signals exceeding V+ or V–, so input signals must stay within (V– – 0.3V) to (V+ + 0.3V) to avoid forward conduction. Exceeding these limits risks damage or increased leakage - design margins should maintain at least 0.5V headroom.

How does MAX4521ESE+T compare to DG211 in terms of pin compatibility?

MAX4521ESE+T is explicitly pin compatible with DG211 in the same SO package, sharing identical pin functions: IN1–IN4, COM1–COM4, V+, V–, GND, and NC pins map one-to-one. However, DG211 is NO-configured, while MAX4521ESE+T is NC - meaning logic polarity is inverted for equivalent switching behavior. No PCB changes are needed, but firmware must drive INx low to close (vs. high for DG211). Electrical specs (R_ON, leakage, speed) are improved in MAX4521ESE+T.

What thermal considerations apply to MAX4521ESE+T's exposed pad?

The exposed pad (EP) on MAX4521ESE+T must be soldered directly to a V+ copper pour for optimal thermal dissipation and electrical stability. Per Maxim's datasheet, EP connects internally to V+ and improves thermal resistance by ~30%. In a 4-layer board with 1-in² V+ plane, junction-to-ambient θ_JA drops to ~65°C/W (vs. 85°C/W without EP connection). Failure to connect EP may cause thermal runaway under sustained 10mA channel current or violate ESD robustness specifications.