Analog Devices Inc./Maxim Integrated MAX1792EUA33+

Overview

MAX1792EUA33+ from Maxim Integrated is a 500mA, 3.3V fixed-output low-dropout linear regulator featuring an internal PMOS pass transistor, ±1% output voltage accuracy over temperature and load, 130mV dropout at full load, and integrated active-low open-drain reset with 4ms timeout-designed for power rail regulation in portable battery-powered systems such as notebook computers and USB hubs.

For engineers reviewing the MAX1792EUA33+ datasheet, MAX1792EUA33+ pinout, MAX1792EUA33+ application, or MAX1792EUA33+ equivalent, key selection criteria include guaranteed 500mA output under 130mV dropout, 80µA ground current at light load, 0.1µA shutdown current, thermal and short-circuit protection, and compatibility with 3.3µF low-ESR output capacitors for stable operation.

Technical Context

The MAX1792EUA33+ employs a P-channel MOSFET pass element with 0.25Ω R_DS(ON), enabling low dropout and eliminating base-drive current loss typical of PNP-based regulators. Its Dual Mode™ architecture selects between factory-trimmed 3.3V output (SET grounded) or adjustable mode via external resistor divider (SET biased to 1.25V reference).

Internal circuitry includes a 1.25V bandgap reference, error amplifier, thermal shutdown sensor (trip at +170°C, 20°C hysteresis), in-regulation current limit (1.6A), and short-circuit protection (0.55–1.8A). The RST output asserts low when V_OUT falls below 93% of nominal and releases after 4ms once regulation is restored.

Key Specifications

Pinout & Package

The MAX1792EUA33+ is housed in an 8-pin Power-µMAX package (U8E+2 outline) with an exposed thermal pad (EP) on the underside for enhanced heat dissipation. Both IN and OUT pins are dual-bonded to reduce trace inductance and improve current handling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with TPS76333DBVR and MCP1703T-3302E/MB, the MAX1792EUA33+ uniquely combines 500mA capability, 130mV dropout, integrated reset, and full protection suite-making it suitable for demanding portable and infrastructure applications where reliability and feature integration outweigh minimal IQ differences.

Availability

MAX1792EUA33+ is available at Aetrix Electronics and suitable for notebook computers, cellular telephones, and USB hubs requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX1792EUA33+ 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 is a semiconductor company specializing in analog and mixed-signal ICs for power management, sensing, and connectivity applications.

The MAX1792 belongs to Maxim's low-dropout linear regulator product line, engineered for battery-powered portable electronics where efficiency, small size, and integrated supervision functions are critical.

FAQ

What is the maximum input voltage for the MAX1792EUA33+?

The MAX1792EUA33+ supports an input voltage range of +2.5V to +5.5V. Operation above +5.5V violates absolute maximum ratings and may cause permanent damage. For robust design, maintain VIN ≤ VOUT + 0.5V in normal regulation, though the device tolerates up to +5.5V regardless of output setting. The MAX1792EUA33+ also includes undervoltage lockout (UVLO) that disables regulation below ~2.15V to prevent erratic behavior during brownout.

Does the MAX1792EUA33+ require external components to operate?

Yes-the MAX1792EUA33+ requires at minimum a 1µF ceramic capacitor from IN to GND and a 3.3µF low-ESR (≤0.1Ω) capacitor from OUT to GND for stable operation across temperature and load. A 100kΩ pullup resistor from RST to OUT is needed if using the reset function. The SET pin must be tied to GND for fixed 3.3V operation. These external components are mandatory per the datasheet to ensure stability, transient response, and proper reset timing in the MAX1792EUA33+.

Can the MAX1792EUA33+ be used in adjustable-output mode?

Yes-the MAX1792EUA33+ supports adjustable output from 1.25V to 5.0V by connecting the SET pin to a resistive divider between OUT and GND instead of grounding it. The internal 1.25V reference is compared against the SET node voltage; R1 and R2 are selected using R1 = R2 × ((VOUT / 1.25V) − 1). However, the part number MAX1792EUA33+ denotes factory-trimmed 3.3V output, so adjustable mode requires verifying layout and feedback network integrity-not a change to the device itself. The MAX1792EUA33+ retains all specifications (e.g., accuracy, dropout) in adjustable mode per datasheet conditions.

How does the reset output (RST) behave during shutdown?

When SHDN is pulled low, the MAX1792EUA33+ enters shutdown mode: the pass transistor turns off, OUT is discharged through an internal 5kΩ resistor, and the RST pin is actively held low-regardless of the actual VOUT level. This ensures a defined reset state during system sleep. RST returns to high-impedance only after SHDN is released *and* VOUT rises above 93% of 3.3V (≈3.069V) for ≥4ms. Thus, RST is not functional as a POR signal during shutdown; it serves solely as an output-voltage monitor in active mode for the MAX1792EUA33+.

What thermal design considerations apply to the MAX1792EUA33+?

The MAX1792EUA33+ uses an exposed thermal pad (EP) and GND pin as primary heat paths. To achieve its 1.3W continuous power dissipation rating, both EP and pin 5 (GND) must be soldered to a large PCB ground plane with ≥4 thermal vias. Without this, junction temperature can exceed +150°C even at moderate loads. Thermal shutdown activates at +170°C but is a safety limit-not a design target. For reliable operation, calculate power dissipation as P = IOUT × (VIN − 3.3V) and verify θ_JA meets ambient requirements using the MAX1792EUA33+'s recommended land pattern (outline 21-0107).