Analog Devices Inc./Maxim Integrated MAX1982EUT-T

Overview

MAX1982EUT-T from Maxim Integrated is a low-voltage, low-dropout linear regulator with external 5V bias supply input, delivering a fixed 1.2V ±3% output at up to 300mA from an input voltage range of 1.25V to 5.5V. It features an open-drain PGOOD output with 1ms rising-edge propagation delay, thermal shutdown, and current limiting - designed specifically for VID power supplies in notebook computers and PDAs.

For engineers reviewing the MAX1982EUT-T datasheet, MAX1982EUT-T pinout, MAX1982EUT-T application, or MAX1982EUT-T equivalent, key selection criteria include dropout voltage (175mV at 150mA), ±3% output accuracy over -40°C to +85°C, 5µA max shutdown current, 6-pin SOT23 package compatibility, and external BIAS-driven N-channel pass transistor architecture.

Technical Context

The MAX1982EUT-T uses an external 4.5V–5.5V BIAS supply to drive the gate of its internal N-channel pass transistor, decoupling control circuitry power from the regulated output path. This architecture enables operation with VIN as low as 1.25V while maintaining regulation at 1.2V output.

It integrates a precision 0.8V reference, error amplifier, current-sense circuitry, and thermal shutdown at +160°C with 20°C hysteresis. The PGOOD comparator monitors VOUT against –9% to –12.5% threshold with 10mV hysteresis and asserts after 1ms stable regulation.

Key Specifications

Pinout & Package

MAX1982EUT-T is housed in a RoHS-compliant, lead-free 6-pin SOT23-6 package (top mark: ABEA), with thermal pad omitted - standard footprint compatible with automated assembly and reflow.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout linear regulator applications.

Compared with TPS79512DCQ and ADP1706ACBZ-1.2-R7, the MAX1982EUT-T uniquely supports sub-1.3V input operation via external BIAS, delivers guaranteed PGOOD timing for CPU sequencing, and achieves lower dropout at mid-load - making it irreplaceable in VID-constrained notebook designs.

Availability

MAX1982EUT-T is available at Aetrix Electronics and suitable for notebook computers, VID power supplies, and mobile PDAs requiring stable component supply with guaranteed long-term lifecycle support and traceable sourcing.

Supply support for MAX1982EUT-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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for computing, communications, and industrial applications.

The MAX1982EUT-T belongs to Maxim's low-voltage LDO family engineered for battery-powered portable systems - prioritizing ultra-low-input operation, tight output accuracy, and robust fault protection in space- and power-constrained environments.

FAQ

What is the minimum input voltage required for MAX1982EUT-T to regulate 1.2V output?

The MAX1982EUT-T requires a minimum input voltage of 1.25V to maintain 1.2V regulation, enabled by its external 5V BIAS supply driving the N-channel pass transistor gate. At 150mA load, dropout is specified at 175mV - meaning VIN must exceed 1.375V for stable operation. Below 1.25V, the device enters dropout and VOUT falls linearly with VIN.

Does MAX1982EUT-T require an external feedback resistor network?

No, the MAX1982EUT-T provides a fixed 1.2V output and does not require external feedback resistors. Unlike the adjustable MAX1983 variant, the MAX1982EUT-T integrates internal resistor division and reference - simplifying layout and eliminating trimming components. Its pin 4 is PGOOD, not ADJ, confirming fixed-output configuration.

How does the PGOOD output of MAX1982EUT-T behave during startup and fault conditions?

The MAX1982EUT-T PGOOD output is an open-drain signal that transitions high ≥1ms after VOUT reaches regulation (within 10% of 1.2V). It pulls low within 10µs if VOUT drops >120mV (e.g., overload or input collapse) or when SHDN is asserted. A 100kΩ pull-up to BIAS is recommended to minimize current draw while ensuring clean logic-level signaling.

Can MAX1982EUT-T operate without the BIAS supply connected?

No - the MAX1982EUT-T requires a valid 4.5V–5.5V BIAS supply to power its control circuitry and drive the gate of the internal N-channel pass transistor. Without BIAS, the device cannot regulate: IN and OUT remain unconnected internally, and PGOOD stays low. BIAS must be present before or simultaneously with VIN to ensure proper startup.

What thermal protection features are implemented in MAX1982EUT-T?

The MAX1982EUT-T includes thermal shutdown triggered at +160°C junction temperature, with 20°C hysteresis - resuming regulation only after die cools to +140°C. It also incorporates current limiting (330–1400mA depending on VIN–VOUT differential) to reduce power dissipation during overload. These features prevent permanent damage during sustained short-circuit or high-ambient conditions in compact SOT23 layouts.