Analog Devices Inc./Maxim Integrated MAX1663EUB

Overview

MAX1663EUB from Maxim Integrated is a serial-to-parallel/parallel-to-serial converter and load-switch controller designed for P-channel MOSFET power-plane switching in notebook computers. It features three +28V-tolerant bidirectional I/O pins, SMBus 2-wire interface, ultra-low 3µA supply current, and high-impedance power-up state to ensure safe power sequencing. It operates from +2.7V to +5.5V and is housed in a 10-pin µMAX package.

For engineers reviewing the MAX1663EUB datasheet, MAX1663EUB pinout, MAX1663EUB application, or MAX1663EUB equivalent, this device serves as a low-power, SMBus-addressable I/O expander with thermal/overcurrent protection, asynchronous suspend-mode register selection via SMBSUS, and hardware/software interrupt support for point-of-load power management in space-constrained portable systems.

Technical Context

The MAX1663EUB implements a dual-register SMBus slave architecture: one normal-data register and one suspend-mode register, selected by the SMBSUS input. This enables asynchronous configuration switching without serial bus latency. Its I/O pins function as open-drain outputs (for driving P-MOSFET gates) or TTL-level inputs (with ±28V tolerance), sampled on SMBCLK falling edges during readback.

It integrates thermal shutdown at +140°C, programmable interrupt masking per I/O pin and START-STOP event, and uses a 7-bit SMBus address determined by the ADD pin's power-on state (GND/High-Z/VCC). The ALERT output is open-drain, active-low, and latched until cleared via Alert Response address (0001100) read.

Key Specifications

Pinout & Package

MAX1663EUB is packaged in a 10-pin µMAX (3mm × 3mm, 0.5mm pitch), thermally enhanced, lead-free surface-mount package with exposed pad for improved heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar load-switch controller applications.

Compared with MAX1662EUB, MAX1663EUB offers distinct SMBus addressing for multi-device systems, while TPS22965DSGR trades protocol intelligence and multi-channel integration for higher current handling in basic enable applications - making MAX1663EUB uniquely suited for coordinated, low-power, SMBus-managed power sequencing.

Availability

MAX1663EUB is available at Aetrix Electronics and suitable for notebook power management, point-of-load switching, and smart battery distribution requiring stable component supply and long-term industrial availability.

Supply support for MAX1663EUB 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, computing, and portable applications.

The MAX166x family was developed specifically for SMBus-controlled, low-quiescent-power load switching in space-constrained mobile platforms - emphasizing safe power sequencing, high-voltage I/O tolerance, and interrupt-driven fault response.

FAQ

What is the power-up behavior of the MAX1663EUB?

The MAX1663EUB powers up with all three I/O pins in high-impedance state, ensuring P-channel MOSFETs remain off until explicitly enabled via SMBus command. This guarantees safe power-plane sequencing in systems where uncontrolled turn-on could cause back-feeding or latch-up. The POR delay is voltage- and temperature-dependent, ranging from ~5µs at 5.5V to ~25µs at 2.7V across -40°C to +85°C.

How does the SMBSUS pin affect MAX1663EUB operation?

The SMBSUS pin selects between two independent SMBus data registers in the MAX1663EUB: driving SMBSUS low applies the suspend-mode register contents to the I/O pins, while driving it high applies the normal-mode register. This allows the host to pre-load alternate power configurations and switch between them asynchronously - bypassing SMBus transaction latency and enabling rapid power-state transitions in notebook suspend/resume cycles.

Can MAX1663EUB drive N-channel MOSFETs?

No, the MAX1663EUB is specifically intended for P-channel MOSFETs, as confirmed by its power-up high-impedance output state and design documentation. Driving N-channel devices would require active pull-down and level shifting incompatible with its open-drain I/O structure and +28V tolerance specification. For N-MOSFET control, the MAX1661EUB variant is specified with low-output POR state and identical pinout.

What happens when thermal shutdown activates in MAX1663EUB?

When die temperature reaches +140°C, the MAX1663EUB triggers thermal shutdown: all I/O pins go high-impedance and the THSD bit (bit 3) in the receive-byte status register is set to '1'. The ALERT pin asserts low and remains latched until cleared via Alert Response address (0001100) read. Thermal shutdown is non-maskable and overrides all register settings to protect downstream MOSFETs and power rails.

How is the SMBus address configured on MAX1663EUB?

The MAX1663EUB SMBus address is set at power-on reset by the voltage state of the ADD pin: GND yields 0100010 (0x42), High-Z yields 0111110 (0x7E), and VCC yields 1001010 (0x9A). This state is latched internally and cannot be changed without cycling VCC. Stray capacitance >50pF on the ADD pin may cause misreads, so proper PCB layout and termination are critical for reliable address recognition.