Analog Devices Inc./Maxim Integrated MAX6790TB+

Overview

MAX6790TB+ from Maxim Integrated is a quad-level overvoltage detector IC with open-drain complementary outputs (OV/OV), 1% accurate trip thresholds (0.6024V–0.6146V), 31mV hysteresis, and 5.7µA supply current at 1.8V - designed for precise battery overvoltage monitoring in space-constrained portable medical devices and cordless phones.

For engineers reviewing the MAX6790TB+ datasheet, MAX6790TB+ pinout, MAX6790TB+ application, or MAX6790TB+ equivalent, this device delivers deterministic overvoltage fault detection with latch-and-clear functionality, low-battery immunity down to VBATT = 1.05V, and robust transient rejection - critical for reliable power-path supervision in Li+-based systems.

Technical Context

The MAX6790TB+ implements four independent overvoltage comparators, each referencing an internal 0.6085V bandgap-derived threshold. It features a dedicated active-low CLEAR input with internal pullup to BATT, enabling nonlatching or latched fault reporting based on external control logic.

Its complementary OV (active-low) and OV (active-high) outputs provide direct interface to microcontroller GPIOs or system supervisors without level-shifting. Propagation delay is tightly specified at 30µs (±100mV overdrive) across -40°C to +85°C, and input leakage remains ≤5nA above 0.3V - ensuring minimal divider error in high-impedance sensing networks.

Key Specifications

Pinout & Package

MAX6790TB+ is housed in a 10-pin TDFN package (3mm × 3mm, 0.75mm height) with exposed pad (EP) for thermal enhancement and grounding. Pin 1 is IN1; pin 10 is BATT. The EP must be soldered to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar overvoltage detection applications.

Compared with MAX6789TB+, MAX6790TB+ trades push-pull OV for open-drain flexibility and lower I_OH drive strength, while retaining identical threshold accuracy and latch timing; versus TLV809E, it adds quad-channel supervision, CLEAR control, and dual-output signaling - enabling more robust system-level fault management.

Availability

MAX6790TB+ is available at Aetrix Electronics and suitable for portable medical devices, cordless phone battery packs, electronic toys with rechargeable packs, and PDAs requiring stable component supply with full RoHS compliance and traceable sourcing.

Supply support for MAX6790TB+ 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 power, sensing, and interface applications, with emphasis on ultra-low-power and high-accuracy performance.

The MAX6782–MAX6790 family was engineered specifically for battery-powered systems needing multi-level voltage supervision - delivering 1% threshold accuracy, sub-6µA quiescent current, and configurable hysteresis in miniature TDFN/TQFN packages.

FAQ

What is the function of the CLEAR pin on the MAX6790TB+?

The CLEAR pin is an active-low input that resets the latched OV and OV outputs when pulled below 0.3×VBATT. It features an internal 25–80kΩ pullup resistor to BATT, allowing the device to default to latched behavior upon power-up. When held low, MAX6790TB+ operates in nonlatching mode - deasserting outputs immediately after the overvoltage condition clears. This enables both fail-safe shutdown and diagnostic-friendly reset control in the same design.

Can the MAX6790TB+ monitor a 4.2V Li+ cell directly?

No - the MAX6790TB+ internal threshold is fixed at ~0.6085V, so a resistive divider is required to scale the 4.2V cell voltage down to the input range. For example, a 6.92:1 divider (R1 = 592kΩ, R2 = 100kΩ) yields 0.607V at 4.2V, staying within the 0.6024V–0.6146V spec. Input leakage ≤5nA ensures minimal divider error, and the device's reverse-battery protection tolerates miswiring if the divider's Thevenin impedance stays ≥1kΩ.

How does the hysteresis work in the MAX6790TB+?

The MAX6790TB+ has fixed 31mV hysteresis between rising and falling thresholds - meaning the rising trip point is 0.6085V and the falling point is 0.5775V. This gap prevents output chatter during slow battery voltage recovery after overvoltage removal. Unlike earlier family members, MAX6790TB+ does not support adjustable hysteresis; its value is factory-trimmed and unchangeable, simplifying design for consistent fault-response behavior across temperature and unit variance.

What is the minimum battery voltage at which MAX6790TB+ guarantees correct output logic states?

MAX6790TB+ guarantees valid OV and OV logic states down to VBATT = 1.05V, as confirmed in the datasheet's "Guaranteed Valid Low-Battery-Output Logic State Down to VBATT = 1.05V" feature list. Below this, output behavior is unspecified. At 1.05V, the device still draws only 5.7µA (typical), making it suitable for end-of-life battery detection in long-life applications like smoke detectors or asset trackers.

Is the MAX6790TB+ RoHS-compliant and lead-free?

Yes - the "+" suffix in MAX6790TB+ explicitly denotes a lead(Pb)-free and RoHS-compliant package per Maxim's ordering nomenclature. The device uses a matte-tin finish on all leads and complies with JEDEC J-STD-020 moisture sensitivity level 1 (MSL-1) for unlimited floor life at ≤30°C/60% RH. Full RoHS documentation and substance declarations are available through Analog Devices' product page for MAX6790TB+.