Analog Devices Inc./Maxim Integrated MAX16024LTBL33+

Overview

The MAX16024LTBL33+ from Maxim Integrated is a low-power, 10-pin TDFN battery-backup circuit with integrated 3.3V LDO regulator, microprocessor reset supervisor, battery switchover control, chip-enable gating, and battery-on indicator. It delivers up to 100mA output current, operates from 1.53V to 5.5V input, consumes only 4µA typical supply current, and supports industrial temperature range (–40°C to +85°C). It is used to back up SRAM or RTCs during main power brownout.

For engineers reviewing the MAX16024LTBL33+ datasheet, MAX16024LTBL33+ pinout, MAX16024LTBL33+ application, or MAX16024LTBL33+ equivalent, key selection considerations include its push-pull reset output, fixed 3.3V regulated output, 4.63V reset threshold, CEIN/CEOUT signal gating with 1.5ns propagation delay, and battery-on status indication - all in a compact 3mm × 3mm TDFN-EP package.

Technical Context

The MAX16024LTBL33+ integrates a low-dropout linear regulator (LDO) with 150mV dropout at 50mA, a precision reset supervisor with 145ms timeout and 20µs VCC-falling delay, and a dedicated battery switchover path that activates when VCC falls below 4.63V, VCC < VBATT, and the LDO enters dropout. Its internal CE gating logic ensures CMOS RAM write protection during power failure by disabling CEOUT for 12µs after reset assertion.

Unlike the MAX16023, this variant includes SET pin for adjustable output (not used here), BATT ON active-high output indicating backup mode, and CEIN/CEOUT transmission gate with 8Ω on-resistance and 1.5ns propagation delay. The device uses an internal 30kΩ MR pullup and supports debounced manual reset with 100ns glitch immunity.

Key Specifications

Pinout & Package

MAX16024LTBL33+ is housed in a 10-pin 3mm × 3mm TDFN-EP package with exposed pad (internally connected to GND) for thermal dissipation. Pin 1 is marked by dot; EP must be soldered to a large ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar battery-backup supervisor applications.

Compared with MAX16024LTBS25+, the MAX16024LTBL33+ offers higher output voltage compatibility with 3.3V peripherals and tighter reset threshold margin for noisy 5V rails; compared with MAX16023LTBL33+, it adds critical CE signal integrity protection and real-time battery-mode visibility - essential for mission-critical data retention.

Availability

MAX16024LTBL33+ is available at Aetrix Electronics and suitable for real-time clock backup, SRAM data retention, GPS module power management, and point-of-sale terminal memory backup requiring stable component supply across industrial temperature ranges and long-life battery operation.

Supply support for MAX16024LTBL33+ 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 semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The MAX16024 belongs to Maxim's battery backup supervisor product line, designed specifically to eliminate external discrete components in memory backup systems while providing integrated reset supervision, CE signal protection, and battery-status awareness.

FAQ

What is the function of the SET pin on the MAX16024LTBL33+?

The SET pin on the MAX16024LTBL33+ is reserved for adjustable-output versions of the MAX16024. Since the MAX16024LTBL33+ has a factory-trimmed fixed 3.3V output, the SET pin must be connected to GND per datasheet guidance. Leaving it floating or applying voltage may cause undefined behavior or damage. This pin is inactive in all fixed-voltage variants including MAX16024LTBL33+.

Does the MAX16024LTBL33+ support open-drain reset output?

No, the MAX16024LTBL33+ features a push-pull RESET output, as indicated by the "L" in its part number suffix (LTBL33+). Push-pull configuration eliminates the need for an external pullup resistor and ensures fast, rail-to-rail reset assertion/deassertion. Open-drain variants exist (e.g., MAX16024PTBL33+) but are distinct orderable parts with different suffixes and electrical behavior.

How does the battery freshness seal work in the MAX16024LTBL33+?

The battery freshness seal in the MAX16024LTBL33+ disconnects the BATT pin from internal circuitry until VCC is applied for the first time. This prevents backup battery self-discharge during storage or assembly. Once VCC rises above ~1.53V, the internal latch engages, enabling BATT to power the LDO during subsequent brownouts. The seal remains active until initial power-up, ensuring full battery capacity at end-user deployment.

Can the MAX16024LTBL33+ monitor a secondary power rail using PFI/PFO?

No - the MAX16024LTBL33+ does not include the PFI (power-fail input) and PFO (power-fail output) pins. These are present only on MAX16023 variants (8-pin TDFN). The MAX16024LTBL33+ replaces those pins with CEIN, CEOUT, BATT ON, and SET - confirming its focus on CE-gated memory backup rather than auxiliary voltage monitoring. For dual-rail monitoring, MAX16023LTBL33+ or separate supervisor ICs are required.

What is the maximum continuous output current supported by the MAX16024LTBL33+?

The MAX16024LTBL33+ supports up to 100mA continuous output current from its 3.3V LDO under specified conditions (VCC ≥ 2V, TA ≤ +85°C). This is validated across temperature and input voltage range per datasheet Electrical Characteristics table. Exceeding 100mA may trigger thermal shutdown or degrade regulation accuracy; short-circuit duration is limited to 10 seconds maximum to prevent permanent damage.