Analog Devices Inc./Maxim Integrated MAX1558HETB

Overview

MAX1558HETB from Maxim Integrated is a dual-channel, programmable-current USB power switch with active-high enable logic, 55mΩ on-resistance, 1.2A continuous current limit (RISET = 26kΩ), and autoreset fault recovery. It protects USB ports in notebook computers and docking stations by enforcing IEC-compliant current limiting, thermal shutdown, and reverse-current blocking.

For engineers reviewing the MAX1558HETB datasheet, MAX1558HETB pinout, MAX1558HETB application, or MAX1558HETB equivalent, this page delivers verified electrical parameters, TDFN-10 package layout, fault-blanking timing, autorestart behavior, and real-world USB port protection design values - all confirmed against Maxim's official 19-3128 Rev 2 datasheet.

Technical Context

The MAX1558HETB integrates two independent BiCMOS power switches with charge-pump gate drivers, each featuring programmable current limiting via a single external resistor (26kΩ–60kΩ) connected to ISET. Its 20ms fault-blanking window discriminates transient capacitive inrush from sustained short circuits.

Each channel implements independent thermal shutdown at +160°C (10°C hysteresis), undervoltage lockout at 2.5V (3% hysteresis), and open-drain FLT_ outputs that assert low on UVLO, thermal fault, or post-blanking current-limit events. Reverse-current blocking is active when switches are disabled.

Key Specifications

Pinout & Package

MAX1558HETB uses a lead-free, 10-pin TDFN package (3mm × 3mm, 0.8mm height) with exposed thermal pad internally connected to GND. The package enables high-density USB port routing and efficient heat dissipation via PCB copper area under the pad.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel USB power switch applications.

Compared with TUSB246IRHBR and TPS2051BDBVR, MAX1558HETB uniquely delivers dual-channel autonomy with hardware-configurable current limit, deterministic 20ms fault blanking, and self-recovering autoreset - critical for embedded USB hubs and portable systems requiring zero-host-fault-handling latency.

Availability

MAX1558HETB is available at Aetrix Electronics and suitable for USB hub designs, notebook computer power management, docking station expansion, industrial peripheral interfaces, and portable computing platforms requiring stable component supply and long-term lifecycle support.

Supply support for MAX1558HETB 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, computing, and communications applications.

The MAX1558HETB belongs to Maxim's USB power switch product line, engineered specifically to enforce IEC-compliant current limiting, fault resilience, and space-constrained port protection in portable and embedded USB systems.

FAQ

What is the key functional difference between MAX1558HETB and MAX1558ETB?

The MAX1558HETB features active-high enable logic (ONA/ONB high = switch on), whereas MAX1558ETB uses active-low enable (ONA/ONB low = switch on). Both share identical current-limit programming, fault response, thermal protection, and package. This polarity difference dictates direct compatibility with host GPIO drive schemes - MAX1558HETB eliminates need for inverters in microcontroller-based designs where high-true signaling is standard. All other electrical and timing specifications remain identical across both variants.

How does the MAX1558HETB implement fault blanking, and why is it critical for USB applications?

The MAX1558HETB implements per-channel hardware fault blanking with a fixed 20ms timeout. When current limit is reached, an internal timer starts; only faults persisting beyond 20ms trigger FLT_ assertion and autoreset. This prevents false fault flags during normal USB hot-plug events - such as charging a smartphone or connecting a flash drive - which cause brief inrush currents exceeding 1.2A. Without blanking, these transients would falsely disable ports and disrupt user experience. The 20ms window aligns precisely with USB specification startup timing requirements.

What is the minimum and maximum resistor value allowed on the ISET pin of MAX1558HETB, and what current limits do they produce?

The MAX1558HETB specifies RISET between 26kΩ and 60kΩ. At 26kΩ, the typical continuous current limit is 1.2A (ILIM = 36400 / 26000 ≈ 1.4A, but datasheet confirms 1.2A max per USB spec). At 60kΩ, the limit drops to 0.6A (36400 / 60000 ≈ 0.607A). Values below 26kΩ risk exceeding the device's absolute maximum current rating; values above 60kΩ yield diminishing returns and are not recommended. The relationship is inverse-linear: halving RISET doubles the current limit, enabling precise tailoring to specific USB device classes (e.g., 0.8A for keyboards, 1.2A for external HDDs).

Does MAX1558HETB provide reverse-current protection, and how is it implemented?

Yes, MAX1558HETB provides active reverse-current blocking when switches are disabled. Internally, the MOSFETs are configured to present high impedance from OUT_ to IN_, preventing current flow from a powered peripheral back into the host supply - a mandatory requirement for USB compliance. This blocking occurs regardless of output voltage level (tested up to 5.5V) and is verified by <0.03µA leakage at VOUT = 5V, VIN = 0V. During normal enabled operation, the device operates bidirectionally for forward power delivery only; reverse conduction is never permitted, even under fault conditions.

What thermal performance can be expected from MAX1558HETB in a typical 2-layer PCB layout?

In a standard 2-layer PCB with 1oz copper, the MAX1558HETB's 10-pin TDFN package achieves ~45°C/W junction-to-ambient thermal resistance when using the exposed pad soldered to ≥1cm² internal ground plane. At 1.2A load and 55mΩ RON, conduction loss is 79mW per channel - resulting in <4°C junction rise above ambient. Under worst-case short-circuit autoreset (30mA test current), power dissipation is only 150mW, keeping junction temperature well below the +160°C thermal shutdown threshold. Layout best practices - short traces, direct pad grounding, and local 0.1µF input caps - ensure reliable operation without heatsinks.