Analog Devices Inc./Maxim Integrated MAX8559ETAAA+T

Overview

MAX8559ETAAA+T from Maxim Integrated is a dual, low-noise, low-dropout linear regulator delivering two independent 3.3V outputs at up to 300mA each, operating from 2.5V–6.5V input, with 60mV dropout at 100mA, 32µVRMS output noise, and 70dB PSRR at 10kHz - deployed in portable battery-powered systems requiring clean, stable dual-rail power.

For engineers reviewing the MAX8559ETAAA+T datasheet, MAX8559ETAAA+T pinout, MAX8559ETAAA+T application, or MAX8559ETAAA+T equivalent, key selection criteria include factory-preset dual 3.3V outputs, independent logic-controlled shutdown (SHDNA/SHDNB), ultra-low quiescent current (115µA per LDO), TDFN-EP package thermal performance, and bypass-capacitor-free operation capability.

Technical Context

The MAX8559ETAAA+T integrates two independent P-channel MOSFET pass transistors (0.6Ω R_DS(ON)) with internal 1.25V bandgap reference and error amplifiers, enabling load-proportional dropout and eliminating base-drive current loss typical of PNP-based regulators. Each LDO features autonomous current limiting (310mA min), thermal shutdown (+160°C), and internal 385Ω discharge path during shutdown.

Its BP pin accepts a 0.01µF ceramic capacitor to form an RC lowpass filter that reduces broadband output noise to ≤32µVRMS (100Hz–100kHz); removal of BP capacitor enables minimal-footprint designs at the cost of higher noise. The device supports stable operation with 2.2µF output capacitors for ≤150mA loads or 4.7µF for full 300mA per rail.

Key Specifications

Pinout & Package

MAX8559ETAAA+T is packaged in an 8-pin TDFN-EP (3mm × 3mm, 0.8mm height) with exposed thermal pad soldered to PCB ground plane for 1.95W power dissipation capability and enhanced thermal management.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A203333PDBVR and ADP5052ACPZ-3.3, MAX8559ETAAA+T uniquely combines factory-preset dual 3.3V outputs, 60mV dropout, 32µVRMS noise via BP bypass, and 115µA IQ - making it optimal for compact, battery-sensitive designs where rail isolation and ultra-low noise are non-negotiable.

Availability

MAX8559ETAAA+T is available at Aetrix Electronics and suitable for cellular handsets, digital cameras, notebook subsystems, and wireless LAN cards requiring stable component supply across extended production lifecycles.

Supply support for MAX8559ETAAA+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) designs precision analog, mixed-signal, and power-management ICs for demanding industrial, automotive, and portable applications.

The MAX8559 belongs to Maxim's low-noise, low-IQ linear regulator product line - engineered specifically for battery-powered portable electronics needing dual independent rails with minimal solution size and maximum efficiency.

FAQ

What output voltages does the MAX8559ETAAA+T provide?

The MAX8559ETAAA+T is factory-configured with dual 3.3V outputs (VOUTA = VOUTB = 3.3V), as indicated by the "AA" suffix in the top-mark code "APD". This eliminates the need for external feedback resistors and ensures ±3% output accuracy across -40°C to +85°C and 0.1mA–300mA load range. No configuration or programming is required to achieve these fixed outputs.

Can the MAX8559ETAAA+T operate without the BP bypass capacitor?

Yes, the MAX8559ETAAA+T is fully functional without the 0.01µF BP capacitor. Omitting it reduces total solution size and cost but increases output noise from 32µVRMS to 254µVRMS (100Hz–100kHz). The regulator remains stable with standard 2.2µF–4.7µF output capacitors. Use BP only when ultra-low noise is mandatory - e.g., for RF VCO or high-resolution ADC supplies.

What is the thermal performance difference between the TDFN and UCSP packages of the MAX8559?

The MAX8559ETAAA+T uses the 8-pin TDFN-EP package, rated for 1.95W continuous power dissipation at +70°C ambient (derating 24.4mW/°C above). In contrast, the UCSP variant (e.g., MAX8559EBAxy+T) is limited to 379mW (derating 4.7mW/°C). The TDFN's exposed paddle, when soldered to a 4-layer PCB ground plane, achieves significantly lower junction-to-ambient thermal resistance - essential for sustained 300mA operation per rail.

How does the MAX8559ETAAA+T handle short-circuit conditions?

The MAX8559ETAAA+T incorporates two independent current limiters - one per LDO - that clamp output current at 310mA (min) by regulating the gate voltage of its internal P-channel MOSFET pass transistors. During a sustained short to ground, the device remains functional and self-protecting without damage. Thermal shutdown activates if junction temperature exceeds +160°C, cycling the output until safe temperature is restored.

Is the MAX8559ETAAA+T pin-compatible with other MAX8559 variants?

Yes, all MAX8559 variants - including MAX8559ETAAA+T (TDFN), MAX8559EBAxy+T (UCSP), and MAX8559ETAxy-T - share identical pinouts and electrical behavior. The TDFN and UCSP packages have the same 8-terminal arrangement (INA, SHDNA, SHDNB, INB, OUTB, GND, BP, OUTA) and functionally equivalent internal circuitry. Only package dimensions, thermal ratings, and marking differ - enabling drop-in replacement based on board space and thermal needs.