Analog Devices Inc./Maxim Integrated MAX4543EKA-T

Overview

The MAX4543EKA-T from Maxim Integrated is a precision dual SPST analog switch with one normally open (NO) and one normally closed (NC) channel, designed for single +2.7V to +12V supply operation. It delivers 60Ω max on-resistance, 2Ω max R_ON matching between channels, 5pC max charge injection, and guaranteed break-before-make switching - enabling reliable signal routing in battery-powered instrumentation and mixed-signal interfaces.

For engineers reviewing the MAX4543EKA-T datasheet, MAX4543EKA-T pinout, MAX4543EKA-T application, or MAX4543EKA-T equivalent, key selection criteria include its SOT23-8 package, -40°C to +85°C industrial temperature range, TTL/CMOS logic compatibility, low leakage (<10nA at +85°C), and verified break-before-make timing (2ns–10ns delay) critical for avoiding signal contention in multiplexed data paths.

Technical Context

The MAX4543EKA-T integrates two independent analog switches in a single die: Channel 1 (COM1/IN1/NO1/NC1) and Channel 2 (COM2/IN2/NO2/NC2), each with complementary NO/NC topology. Its CMOS transmission-gate architecture supports bidirectional analog signal flow from GND to V+ with minimal distortion and flat on-resistance over voltage range.

Break-before-make timing is hardware-guaranteed via internal control logic that delays NC turn-on until NO is fully off - confirmed by test circuit Figure 3a and specified t_D = 2ns–10ns (T_A = +25°C). Input logic thresholds are rail-to-rail compatible across supply voltages, and ESD protection exceeds 2000V per Method 3015.7.

Key Specifications

Pinout & Package

MAX4543EKA-T is housed in an 8-pin SOT23-8 package (top mark: AAAG), with exposed pad not connected internally. Pin functions are validated per datasheet Figures and Pin Configurations section (page 11).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX4543ETA, the MAX4543EKA-T trades thermal capability for lower assembly cost and simpler layout; versus ADG1419BRMZ, it offers guaranteed break-before-make and single-supply simplicity at the expense of bipolar operation - making it the only choice for robust, low-voltage SPDT emulation in portable instrumentation.

Availability

MAX4543EKA-T is available at Aetrix Electronics and suitable for battery-operated medical devices, industrial sensor multiplexers, and portable test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX4543EKA-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) designs precision analog and mixed-signal ICs for industrial, medical, and communications applications, with emphasis on low-power, high-reliability solutions.

The MAX4541–MAX4544 family was engineered specifically for low-voltage, single-supply analog signal routing in space- and power-constrained systems - prioritizing low R_ON, minimal charge injection, and guaranteed switching sequence integrity.

FAQ

What is the maximum supply voltage rating for the MAX4543EKA-T?

The MAX4543EKA-T has an absolute maximum supply voltage (V+) of +13V, but its recommended operating range is +2.7V to +12V. Operation above +12V risks exceeding safe power dissipation limits and may degrade long-term reliability. The device's internal protection diodes clamp signals to V+ + 0.3V, so maintaining V+ ≤ +12V ensures margin for transient spikes while preserving R_ON stability and ESD robustness. Always apply V+ before analog signals per datasheet sequencing guidance.

Does the MAX4543EKA-T support true SPDT functionality?

Yes, the MAX4543EKA-T implements true SPDT functionality through its integrated dual SPST structure: one channel is normally open (NO1), the other normally closed (NC1), both sharing COM1. When IN1 is low, NC1 connects COM1 to its path; when IN1 is high, NO1 connects instead - with hardware-enforced break-before-make timing (2–10ns) preventing overlap. This configuration matches discrete SPDT behavior without external components, unlike the MAX4544 which uses a dedicated SPDT topology. The MAX4543EKA-T's truth table and functional diagrams (page 11) confirm this operation.

What is the guaranteed break-before-make timing for the MAX4543EKA-T?

The MAX4543EKA-T guarantees a break-before-make (B-B-M) time delay (t_D) of 2ns minimum to 10ns maximum at T_A = +25°C, as measured under RL = 300Ω and CL = 35pF conditions (Figure 3a). This parameter is production-tested and applies only to the MAX4543 and MAX4544 variants - not the MAX4541/MAX4542. The delay ensures NC1 disconnects completely before NO1 closes, eliminating signal shorting during transitions. At temperature extremes (-40°C/+85°C), t_D remains within specification due to process characterization, though typical values shift slightly per Figure 4's timing curves.

Can the MAX4543EKA-T operate from a +3.3V supply?

Yes, the MAX4543EKA-T is fully specified for +3.3V operation (V+ = +3.0V to +3.6V), with characterized parameters including 125Ω max R_ON, 80ns–400ns t_ON, and 50ns–175ns t_OFF. Logic inputs remain rail-to-rail compatible: driving IN1/IN2 from 0V to +3.3V ensures valid TTL/CMOS thresholds without external level shifting. Charge injection stays at 1–5pC, and leakage remains <10nA at +85°C. However, R_ON increases ~2× versus +5V operation, so designers should verify voltage drop in high-current paths (e.g., >1mA) using the R_ON vs. V_COM curves on page 5.

Is the MAX4543EKA-T pin-compatible with older Maxim analog switches?

Yes, the MAX4543EKA-T is pin-compatible with the MAX323, MAX324, and MAX325 families in the SOT23-8 package, sharing identical pin assignments for COM1, IN1, GND, NC2, COM2, IN2, V+, and NO1 (per datasheet page 11). This allows direct replacement in legacy designs without PCB modification. However, note that MAX323/MAX324 lack break-before-make guarantee and have higher R_ON (100Ω max), so upgrading to MAX4543EKA-T improves switching integrity and signal fidelity - especially in SPDT-emulation use cases where timing and on-resistance matching are critical.