Analog Devices Inc./Maxim Integrated MAX6509CAZK/V+T

Overview

The MAX6509CAZK/V+T from Maxim Integrated is a resistor-programmable temperature switch with open-drain output, designed for precise thermal monitoring in microprocessor systems. It sets trip thresholds from −40°C to +125°C using a single 1% external resistor, achieves ±0.5°C typical threshold accuracy, and operates from +2.7V to +5.5V supply while consuming only 32µA. It is used in µP reset circuits where accurate overtemperature detection triggers system shutdown or alarm.

For engineers reviewing the MAX6509CAZK/V+T datasheet, MAX6509CAZK/V+T pinout, MAX6509CAZK/V+T application, or MAX6509CAZK/V+T equivalent, key selection criteria include its SOT23-5 package, pin-selectable 2°C/10°C hysteresis, set-hot/cold configuration support, and compatibility with low-power embedded thermal management architectures requiring minimal external components.

Technical Context

The MAX6509CAZK/V+T integrates dual temperature-dependent references (one positive, one negative TC) and a comparator to determine trip point based on their voltage equality. Its SET pin connects to GND via an external resistor to program the threshold across −40°C to +125°C, while HYST selects hysteresis (2°C at GND, 10°C at VCC).

It features an active-low open-drain output that sinks current only, requires no pull-up for basic µP interrupt/reset use (though external pull-up may be added), and avoids oscillation near threshold via CMOS-compatible hysteresis control-critical for stable operation in high-speed computing thermal monitoring.

Key Specifications

Pinout & Package

SOT23-5 package with 1.6mm × 2.9mm footprint, 0.95mm height, and gull-wing leads - optimized for space-constrained PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6509HAUK+T, the MAX6509CAZK/V+T provides identical accuracy and power performance but asserts output on temperature decrease - making it essential for low-temperature protection. Versus LM75BIMM/NOPB, it delivers faster, deterministic response without MCU involvement, at lower system-level cost and higher reliability in reset-critical paths.

Availability

MAX6509CAZK/V+T is available at Aetrix Electronics and suitable for microprocessor thermal reset, industrial overtemperature alarms, and fan control applications requiring stable component supply and long-term lifecycle support.

Supply support for MAX6509CAZK/V+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, communications, computing, and automotive markets.

The MAX6509/MAX6510 product line delivers resistor-programmable thermal switches for autonomous, low-power temperature monitoring - targeting applications where simplicity, reliability, and minimal external components outweigh digital configurability.

FAQ

What is the function of the HYST pin on the MAX6509CAZK/V+T?

The HYST pin on the MAX6509CAZK/V+T is a CMOS-compatible input that selects hysteresis magnitude: connecting HYST to GND yields 2°C hysteresis, while connecting to VCC yields 10°C. This prevents output oscillation near the temperature threshold. Leaving HYST unconnected increases supply current and is not permitted per datasheet guidance. The MAX6509CAZK/V+T uses this pin exclusively for hysteresis control - no other functions are assigned to it.

How does the MAX6509CAZK/V+T differ from the MAX6510 series?

The MAX6509CAZK/V+T features a fixed open-drain output, whereas the MAX6510 offers three selectable outputs (active-low, active-high, or open-drain with internal pull-up) controlled by the OUTSET pin. The MAX6509CAZK/V+T uses a 5-pin SOT23 package, while the MAX6510 requires 6 pins. Both share identical threshold programming, accuracy, supply range, and hysteresis options - but MAX6509CAZK/V+T is simpler and lower-cost for applications needing only open-drain assertion.

Can the MAX6509CAZK/V+T be used for undertemperature detection?

Yes - the MAX6509CAZK/V+T is a C-suffix (cold-trip) device, meaning its output asserts when temperature falls below the programmed threshold. For example, with R_SET configured for −40°C, the output goes low as temperature drops to −40°C and releases only after rising above −40°C plus selected hysteresis (e.g., −38°C for 2°C hysteresis). This makes MAX6509CAZK/V+T ideal for battery low-temperature cutoff or cryogenic monitoring.

What is the recommended external pull-up resistor value for the MAX6509CAZK/V+T output?

No external pull-up is strictly required for MAX6509CAZK/V+T operation, as its open-drain output can interface directly with µP reset inputs that have internal pull-ups. If added, a 10kΩ to 100kΩ resistor to VCC is typical - values ≤10kΩ ensure fast rise time for high-speed logic, while ≥47kΩ minimize standby current. The MAX6509CAZK/V+T output sink capability (20mA max) supports robust drive into heavy capacitive loads without degradation.

Does the MAX6509CAZK/V+T require calibration or trimming during production?

No - the MAX6509CAZK/V+T is factory-trimmed for ±0.5°C typical threshold accuracy and requires no end-user calibration. Its resistor-programmable architecture relies solely on a 1% external SET resistor; no trimming pots, EEPROM writes, or firmware calibration steps are needed. All specifications - including hysteresis, supply current, and output behavior - are guaranteed over temperature without adjustment, making MAX6509CAZK/V+T suitable for high-volume, zero-calibration manufacturing.