Analog Devices Inc./Maxim Integrated MAX6459UTB+T

Overview

The MAX6459UTB+T from Analog Devices is a dual high-voltage, low-power voltage monitor IC with independent undervoltage (OUTA) and overvoltage (OUTB) open-drain outputs, 5% internal threshold hysteresis, 50μs timeout, and operation from 4V to 28V supply. It features precision bandgap reference (2.25V ±2.5%), 3.5μA typical supply current at 12V, and operates across –40°C to +125°C - used in multicell Li+ battery-stack undervoltage/overvoltage shutdown circuits.

For engineers reviewing the MAX6459UTB+T datasheet, MAX6459UTB+T pinout, MAX6459UTB+T application, or MAX6459UTB+T equivalent, this page delivers verified electrical parameters, SOT23-6 pin mapping, window detection design guidance, and AEC-Q100-qualified alternative options for automotive and industrial power-rail monitoring.

Technical Context

The MAX6459UTB+T integrates two independent comparators: one configured for undervoltage detection (IN+ vs. VTH−) driving OUTA, and one for overvoltage detection (IN− vs. VTH+) driving OUTB. Both share a common 2.25V internal reference and support external resistor-divider programming of trip thresholds.

It implements fixed 50μs timeout logic on both outputs, no latch functionality (unlike MAX6457), and 5% factory-trimmed hysteresis - eliminating need for external hysteresis networks while ensuring noise immunity in noisy 12–24V systems such as automotive ECUs and telecom power supplies.

Key Specifications

Pinout & Package

SOT23-6 package with exposed pad option not specified; JEDEC-compliant outline 21-0058, land pattern 90-0175, thermal resistance θ_JA = 115°C/W (four-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-threshold voltage monitoring applications.

Compared with TLV809EADBZR and MAX6315US29D3+T, the MAX6459UTB+T uniquely delivers simultaneous, independently configurable undervoltage and overvoltage detection in one SOT23-6 package - essential for safety-critical window monitoring where separate fault signaling and 5% hysteresis are mandatory.

Availability

MAX6459UTB+T is available at Aetrix Electronics and suitable for automotive battery management, industrial DC-DC protection, and telecom power shelf supervision requiring stable component supply and long-term lifecycle assurance.

Supply support for MAX6459UTB+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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The MAX6457–MAX6460 family was designed specifically for high-voltage, low-quiescent-current supervision in harsh environments - targeting multicell battery stacks, automotive power domains, and industrial 24V/48V systems requiring AEC-Q100 qualification and extended temperature operation.

FAQ

What is the function of the OUTA and OUTB pins on the MAX6459UTB+T?

OUTA is the open-drain undervoltage output that asserts low when the voltage at IN+ falls below the programmed VTH− threshold. OUTB is the open-drain overvoltage output that asserts low when the voltage at IN− exceeds the programmed VTH+ threshold. Both outputs operate independently with 50μs timeout and require external pullup resistors. This dual-output architecture enables the MAX6459UTB+T to serve as a window detector or two discrete monitors.

Does the MAX6459UTB+T include an internal voltage reference?

Yes, the MAX6459UTB+T includes a precision 2.25V ±2.5% internal bandgap reference. This reference is used internally to set comparator thresholds and is not accessible externally - unlike the MAX6460, which exposes REF as a pin. The MAX6459UTB+T uses this reference to derive VTH+ and VTH− thresholds for its dual comparators, enabling accurate trip-point programming via external resistor dividers on IN+ and IN−.

What is the meaning of the 'B' suffix in MAX6459UTB+T?

The 'B' in MAX6459UTB+T denotes the factory-trimmed 5% internal threshold hysteresis option. Per Analog Devices' Selector Guide (Rev 9, Oct 2024), MAX6459UTA-T = 0.5%, MAX6459UTB-T = 5%, and MAX6459UTC-T = 8.3%. The '+T' suffix indicates lead(Pb)-free/RoHS-compliant packaging. Therefore, MAX6459UTB+T is the 6-pin SOT23 variant with 5% hysteresis and RoHS compliance.

Can the MAX6459UTB+T monitor voltages higher than its VCC supply?

No - the MAX6459UTB+T's IN+ and IN− inputs have absolute maximum ratings of 0V to VCC + 0.3V, so they cannot directly monitor voltages exceeding VCC. However, its open-drain outputs (OUTA, OUTB) are rated to 28V and can be pulled up to a voltage higher than VCC (up to 28V), enabling interface with higher-voltage logic or control circuits. To monitor voltages above VCC, use external resistor dividers to scale the input within the 0–VCC+0.3V range.

Is the MAX6459UTB+T AEC-Q100 qualified?

No - only the /V variants (e.g., MAX6459UTA/V+T, MAX6459UTB/V+T) are explicitly AEC-Q100 qualified per the "Benefits and Features" section (Rev 9, Oct 2024). The MAX6459UTB+T lacks the '/V' suffix and is specified for the same –40°C to +125°C temperature range but does not carry formal AEC-Q100 certification. For automotive applications requiring qualification, select MAX6459UTB/V+T instead.