Analog Devices Inc./Maxim Integrated MAX1756BAUT

Overview

MAX1756BAUT from Maxim Integrated is a latched SMBus-compatible local temperature comparator IC in 6-pin SOT23 package, featuring ±3°C accuracy (25°C–100°C), 8°C programmable temperature window, and ALERT interrupt output. It operates from +2.375V to +5.5V, draws ≤200µA supply current, and supports thermal monitoring in high-density computing systems where software-controlled trip thresholds are required.

For engineers reviewing the MAX1756BAUT datasheet, MAX1756BAUT pinout, MAX1756BAUT application, or MAX1756BAUT equivalent, this page delivers verified functional identity, validated pin-level circuit roles, confirmed SMBus timing compliance, and real-world thermal windowing use cases - all grounded in Maxim's official 19-1852 Rev 0 datasheet.

Technical Context

The MAX1756BAUT implements a dual-threshold sampling architecture: one DAC sets the rising trip point (TMAX), while a digital subtractor derives the falling threshold (THYST = TMAX − 8°C), enabling precise "windowing" algorithms. Its PTAT voltage generator feeds a low-offset comparator shared between both thresholds via time-multiplexed sampling at ~1kHz.

It uses a static SMBus 2-wire interface supporting Send Byte/Receive Byte protocols only - no command byte, no Alert Response - with strict DC–100kHz clock compliance. The ADD pin selects one of three slave addresses (0011010b for MAX1756B tied to VCC), allowing up to six devices per bus without conflict.

Key Specifications

Pinout & Package

MAX1756BAUT is housed in a 6-pin SOT23 package (JEDEC MO-178AA), with 1.3mm × 2.9mm footprint and 1.0mm max height. Thermal resistance θ_JA = 110°C/W; recommended solder profile follows IPC/JEDEC J-STD-020A paragraph 7.6, Table 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX1756BAUT, MAX1617AESA+ offers tighter accuracy but lacks latched bidirectional interrupt capability, while LM75BIMM/NOPB provides lower-cost single-threshold monitoring without windowing - neither replicates the MAX1756BAUT's software-adjustable 8°C thermal window and guaranteed interrupt persistence.

Availability

MAX1756BAUT is available at Aetrix Electronics and suitable for server thermal management, notebook GPU monitoring, industrial PLC overheat protection, and automotive infotainment SoC thermal supervision requiring stable component supply across extended temperature ranges.

Supply support for MAX1756BAUT 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 precision analog, mixed-signal, and power management ICs for industrial, computing, and automotive markets.

The MAX1755/MAX1756 product line was designed specifically for SMBus-based local thermal monitoring in space-constrained, high-reliability systems - emphasizing low power, small footprint, and software-configurable trip thresholds.

FAQ

What is the function of the ADD pin on the MAX1756BAUT?

The ADD pin on the MAX1756BAUT selects one of three SMBus slave addresses (0011010b when tied to VCC, per Table 3). It is sampled at power-on reset and when exiting software standby mode, then latched to configure bus addressing - enabling up to six MAX1755/MAX1756 devices on a single SMBus without collision. This pin must be hard-wired to VCC, GND, or left floating; dynamic reconfiguration is not supported.

How does the MAX1756BAUT generate its 8°C temperature window?

The MAX1756BAUT generates its 8°C temperature window by subtracting a fixed 8°C offset from the programmed TMAX value to derive THYST (lower threshold). This subtraction is performed digitally within the IC, ensuring consistent hysteresis independent of process variation. When temperature rises above TMAX, ALERT asserts; when it falls to or below THYST, ALERT reasserts - enabling true bidirectional thermal event detection without external components.

Can the MAX1756BAUT operate from a 2.5V supply?

Yes, the MAX1756BAUT supports supply voltages from +2.375V to +5.5V, making it fully compatible with 2.5V system rails. At 2.5V, all specifications remain valid: SMBus timing parameters (e.g., 4.7µs t_LOW) hold, ALERT sink current remains ≥6mA, and temperature accuracy stays within ±5°C across −40°C to +125°C. Undervoltage lockout activates below ~2.2V, preventing erroneous operation during rail ramp-up.

What happens to the ALERT output after a temperature threshold breach?

After a temperature threshold breach, the ALERT output on the MAX1756BAUT latches low and remains asserted until cleared by either reading the status register or writing a new value to the TMAX register. Unlike self-clearing outputs, this latching behavior guarantees interrupt persistence across firmware execution delays - critical for robust thermal management in real-time systems using the MAX1756BAUT.

Is the MAX1756BAUT pin-compatible with the MAX1755BAUT?

No, the MAX1756BAUT is not pin-compatible with the MAX1755BAUT. While both share the same 6-pin SOT23 package and identical pin 1–3 (ADD, SMBDATA, SMBCLK) and pin 5–6 (VCC, GND), pin 4 differs: MAX1756BAUT uses ALERT (latched interrupt), whereas MAX1755BAUT uses OVERT (self-clearing thermostat). Swapping them without board revision will result in nonfunctional interrupt signaling and potential firmware misinterpretation.