Analog Devices Inc./Maxim Integrated MAX944ESD+T

Overview

The MAX944ESD+T from Maxim Integrated is a quad high-speed comparator optimized for 3V/5V single-supply systems, featuring rail-to-rail inputs, 80ns propagation delay (5mV overdrive), 350μA per comparator supply current, and CMOS/TTL-compatible outputs. It operates from 2.7V to 5.5V and is used in threshold detection, zero-crossing detection, and line receiver circuits where low power and fast response are critical.

For engineers reviewing the MAX944ESD+T datasheet, MAX944ESD+T pinout, MAX944ESD+T application, or MAX944ESD+T equivalent, key selection considerations include guaranteed 80ns propagation delay at 5mV overdrive, rail-to-rail input common-mode range extending beyond both supply rails, output swing within 0.4V of V+ or GND without pullups, internal hysteresis for noise immunity, and 14-pin SO package compatibility with industrial temperature range (-40°C to +85°C).

Technical Context

The MAX944ESD+T implements a bipolar process-based comparator core with internal hysteresis (1mV typical input-referred width), enabling clean switching on slow-moving or noisy signals without external components. Its rail-to-rail input stage accepts voltages from -0.2V to (V+ + 0.2V), and its current-driven output stage delivers VOH ≥ V+ − 0.4V and VOL ≤ 0.4V at 400μA load.

Designed for single-supply operation, it supports direct interfacing to CMOS and TTL logic, tolerates continuous input short-circuit faults to either rail, and maintains stable performance across 2.7V–5.5V supply and -40°C to +85°C ambient. Propagation delay skew between channels is ≤10ns, ensuring precise timing alignment in multi-channel detection.

Key Specifications

Pinout & Package

MAX944ESD+T is housed in a 14-pin narrow SO (Small Outline) package, RoHS-compliant, with standard 1.27mm pitch and exposed pad not present. Pin 11 is GND; pins 1, 4, 6, 9, 12, and 14 are outputs; pins 2, 3, 5, 7, 8, 10, and 13 are inputs; pin 4 is V+.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad high-speed comparator applications.

Compared with LM339DR, MAX944ESD+T delivers 16× faster response and rail-to-rail input flexibility; versus TLV3704IPW, it trades 270μA higher quiescent current for integrated hysteresis and guaranteed 80ns performance across -40°C to +85°C.

Availability

MAX944ESD+T is available at Aetrix Electronics and suitable for industrial automation, battery-powered instrumentation, and communications line receiver designs requiring stable component supply across extended temperature ranges.

Supply support for MAX944ESD+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, mixed-signal, and power management ICs for industrial, automotive, and computing applications.

The MAX94x family was developed specifically for high-speed, low-power, single-supply comparator applications in portable and 3V/5V systems where rail-to-rail input operation and integrated hysteresis are essential.

FAQ

What is the operating temperature range for the MAX944ESD+T?

The MAX944ESD+T is rated for industrial temperature operation from -40°C to +85°C. This range is confirmed in the Ordering Information table and Absolute Maximum Ratings section of the datasheet. All electrical specifications - including propagation delay, offset voltage, and supply current - are guaranteed across this full range. The "E" grade suffix in MAX944ESD+T explicitly denotes this -40°C to +85°C qualification.

Does the MAX944ESD+T include internal hysteresis, and how does it affect design?

Yes, the MAX944ESD+T includes fixed internal hysteresis with a typical input-referred width of 1mV. This eliminates the need for external positive-feedback resistors typically required to stabilize comparators against noise. As stated in the Detailed Description, the hysteresis creates distinct rising and falling trip points, preventing oscillation during slow input transitions. Designers benefit from reduced component count, smaller PCB area, and guaranteed noise immunity without calculating or tuning external networks.

Can the MAX944ESD+T interface directly with 3.3V CMOS logic?

Yes, the MAX944ESD+T can interface directly with 3.3V CMOS logic. Its outputs swing to within 0.4V of V+ and GND (e.g., VOH ≥ 2.9V and VOL ≤ 0.4V at V+ = 3.3V), satisfying standard CMOS VIH/VIL thresholds. The datasheet explicitly states "CMOS/TTL-Compatible Outputs" and confirms output drive capability of 400μA minimum at those voltage levels. No external pull-up resistors or level translators are required for 3.3V logic families.

What is the maximum supply voltage rating for the MAX944ESD+T?

The absolute maximum supply voltage for the MAX944ESD+T is +6.5V referenced to GND, as specified in the Absolute Maximum Ratings table. However, functional operation is guaranteed only from 2.7V to 5.5V per the Electrical Characteristics. Operating above 5.5V may cause parametric degradation or reliability risk, even if below the 6.5V absolute limit. The device is optimized for 3V and 5V systems, and all timing and accuracy specs assume V+ within 2.7V–5.5V.

Is the MAX944ESD+T pin-compatible with other MAX94x variants like the MAX944EPD?

Yes, the MAX944ESD+T is pin-compatible with all 14-pin MAX944 variants, including MAX944EPD (14-pin PDIP) and MAX944CSD (14-pin SO, commercial temp). The Pin Configurations diagram shows identical pin numbering and function mapping across all 14-pin packages. Differences are limited to package type (SO vs. PDIP), temperature grade (E-grade = -40°C to +85°C), and packaging (T = tape-and-reel). Electrical behavior, pinout, and footprint land patterns are identical per the Package Information table.