Analog Devices Inc./Maxim Integrated MAX908CSD

Overview

MAX908CSD from Maxim Integrated is a quad, high-speed, ultra-low-power, single-supply TTL comparator IC designed for precision threshold detection in battery-powered and timing-critical systems. It delivers 40ns propagation delay with 5mV input overdrive, consumes only 700µA per comparator (3.5mW), and operates from a single +5V supply (4.5V to 5.5V). Its input common-mode range extends from −0.2V to V+ − 1.5V, enabling ground-sensing capability in single-supply configurations.

For engineers reviewing the MAX908CSD datasheet, MAX908CSD pinout, MAX908CSD application, or MAX908CSD equivalent, this page provides verified functional identity, validated 14-pin SOIC package mapping, confirmed quad comparator topology, exact propagation delay and power specs, and two industry-validated alternative parts - all derived from Maxim's official datasheet Rev 7 (Jan 2006) and ordering documentation.

Technical Context

The MAX908CSD implements four independent high-gain bipolar comparators with internal hysteresis (5mV typical hysteresis width), eliminating external feedback components. Each channel features TTL-compatible push-pull outputs-no pull-up resistors required-and full short-circuit protection on all inputs and outputs.

It uses a dedicated ground-referenced architecture (GND pin = Pin 11), supports continuous input voltage operation down to −0.2V (below GND), and maintains stable switching even with slow-moving analog inputs due to built-in hysteresis. Unlike the MAX909, it lacks latch functionality, complementary outputs, or dual-supply support-those are exclusive to the MAX909 variant.

Key Specifications

Pinout & Package

MAX908CSD is housed in a 14-pin Small Outline Integrated Circuit (SOIC) package, 3.9mm wide, with standard JEDEC MS-012AC footprint and 1.27mm pitch. Pin 1 is marked by a beveled corner or dot; the device is not RoHS-compliant per Maxim's legacy process.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM339DR and TLV3704IDR, the MAX908CSD uniquely combines TTL compatibility, internal hysteresis, ground-sensing input range, and 40ns speed in a single quad package-making it irreplaceable for compact, high-speed, single-supply threshold detection where layout area and BOM count are constrained.

Availability

MAX908CSD is available at Aetrix Electronics and suitable for battery-powered instrumentation, high-speed data acquisition front-ends, and industrial line receiver designs requiring stable component supply and long-term obsolescence planning.

Supply support for MAX908CSD 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 U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX907/MAX908/MAX909 family was engineered specifically for single-supply, high-speed comparator applications demanding ultra-low power, TTL compatibility, and integrated hysteresis-targeting portable test equipment, precision data converters, and noise-immune signal conditioning.

FAQ

What is the operating temperature range for MAX908CSD?

The MAX908CSD is specified for commercial-grade operation from 0°C to +85°C. This range is confirmed in Maxim's official ordering information table, where "C" suffix denotes 0°C to +70°C and "E" suffix denotes −40°C to +85°C; MAX908CSD carries the "C" designation and is therefore rated 0°C to +70°C. The device may function outside this range, but electrical parameters are only guaranteed within the stated limits.

Does MAX908CSD support dual-supply operation like MAX909?

No, MAX908CSD does not support dual-supply operation. Per Maxim's datasheet General Description and Absolute Maximum Ratings sections, only the MAX909 variant accepts dual ±5V supplies. The MAX908CSD is strictly a single-supply device, rated for +4.5V to +5.5V on V+, with GND as the sole reference. Its input common-mode range extends to −0.2V (below GND), but that is achieved via internal design-not negative rail support.

Is MAX908CSD pin-compatible with other devices in the MAX907/MAX908/MAX909 family?

Yes, MAX908CSD shares identical pinout with all 14-pin SOIC and DIP variants of the MAX908 (e.g., MAX908CPD, MAX908ESD), as shown in the "Pin Configurations" diagram on page 1 of the datasheet. However, it is not pin-compatible with the 8-pin MAX907 or MAX909 - those have different channel counts, output structures (e.g., QOUT/QOUT on MAX909), and pin assignments (e.g., LE, V−).

Can MAX908CSD drive standard TTL loads directly?

Yes, MAX908CSD outputs are fully TTL-compatible push-pull drivers. As confirmed in the Features list and Electrical Characteristics table, VOH ≥ 2.8V at ISOURCE = 100µA and VOL ≤ 0.55V at ISINK = 3.2mA - meeting standard TTL logic thresholds (VIH ≥ 2.0V, VIL ≤ 0.8V). No external pull-up resistors are needed, unlike open-collector comparators such as LM339.

Why does the datasheet state "Not Recommended for New Designs" for MAX908CSD?

The "Not Recommended for New Designs" notice applies to the entire MAX907/MAX908/MAX909 family because Maxim discontinued the legacy bipolar wafer process used to manufacture them. While MAX908CSD remains available through authorized distributors and Aetrix Electronics' legacy inventory, Maxim advises new designs to consider modern alternatives (e.g., MAX9021, TLV3704) offering improved specs, smaller packages, and active support. Lifecycle management support remains available for existing programs.