Analog Devices Inc./Maxim Integrated MAX6956ATL/V+

Overview

The MAX6956ATL/V+ from Maxim Integrated is a 28-port, I²C-compatible LED display driver and GPIO expander operating from 2.5V to 5.5V, supporting constant-current LED sink outputs (16-step programmable, up to 24mA), Schmitt-trigger inputs with selectable pullups, and transition-detection interrupts on seven ports (P24–P30). It targets automotive-grade panel meters and industrial controllers requiring robust, mixed-signal I/O expansion.

For engineers reviewing the MAX6956ATL/V+ datasheet, MAX6956ATL/V+ pinout, MAX6956ATL/V+ application, or MAX6956ATL/V+ equivalent, key selection criteria include its 40-pin thin QFN-EP package with exposed thermal pad, -40°C to +125°C automotive qualification (/V), RoHS-compliant lead-free finish (+), and support for 16 I²C addresses via AD0/AD1 logic-level addressing.

Technical Context

The MAX6956ATL/V+ implements a dual-role port architecture: each of ports P4–P31 is individually configurable as a constant-current LED sink (CA segment driver), push-pull logic output (10mA sink / 4.5mA source), or Schmitt-trigger input (with optional internal pullup). Its I²C interface complies with 400kbps Fast Mode and supports auto-incrementing register access for efficient multi-port writes.

Seven dedicated ports (P24–P30) feature maskable transition detection logic that asserts interrupt on P31 when logic level changes occur; shutdown mode forces all ports to high-impedance inputs while preserving register contents. Current scaling is set globally via external resistor RISET connected to ISET pin, enabling precise per-segment current control across all 28 ports.

Key Specifications

Pinout & Package

MAX6956ATL/V+ is housed in a 40-pin thin QFN package with exposed thermal pad (EP), optimized for high-density PCB layouts and thermal performance in automotive modules. Pin numbering follows standard top-view orientation with pin 1 at bottom-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED driver and I/O expander applications.

Compared with MAX6956ATL/V+, MAX6957ATL/V+ trades I²C compatibility for SPI flexibility and MAX7300ATL+ removes LED driver circuitry to reduce cost and complexity - both retain the same automotive temperature range and QFN-40 packaging but serve distinct system-level roles.

Availability

MAX6956ATL/V+ is available at Aetrix Electronics and suitable for automotive instrument clusters, industrial panel meters, and white goods control panels requiring stable component supply across extended temperature and long product lifecycles.

Supply support for MAX6956ATL/V+ 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 and mixed-signal ICs for demanding industrial, automotive, and communications applications.

The MAX6956 belongs to Maxim's LED display driver and I/O expander product line, engineered specifically for space-constrained, thermally harsh systems needing integrated constant-current LED control and configurable digital I/O in a single chip.

FAQ

What is the package type and thermal pad configuration for MAX6956ATL/V+?

The MAX6956ATL/V+ uses a 40-pin thin QFN package with an exposed thermal pad (EP). The EP is not internally connected but must be soldered to the PCB ground plane to ensure proper thermal dissipation and meet the -40°C to +125°C operating specification. This configuration supports 2105mW continuous power dissipation at TA = +70°C before derating.

How does the MAX6956ATL/V+ achieve 16-step LED current control?

The MAX6956ATL/V+ achieves 16-step LED current control through internal digital-to-analog conversion referenced to the external resistor RISET connected to the ISET pin. Each step scales linearly from 1/16 to 16/16 of the maximum current set by RISET (e.g., 24mA at V+=5.5V with 39kΩ), enabling precise per-segment brightness tuning without external PWM circuitry.

Which ports support transition detection and how is the interrupt signaled?

Ports P24 through P30 support configurable transition detection. A change in logic level on any enabled port triggers a status flag in the transition detect register and asserts an active-low interrupt signal on port P31. The interrupt remains latched until cleared by reading the status register, allowing the host MCU to respond asynchronously without polling.

Can the MAX6956ATL/V+ drive common-anode (CA) LED digits and discrete LEDs simultaneously?

Yes, the MAX6956ATL/V+ can drive both common-anode numeric/alphanumeric digits and discrete LEDs simultaneously. All 28 ports (P4–P31) are independently configurable as constant-current LED sinks. When used with CA digits, the MAX6956ATL/V+ sinks current from segment anodes tied to V+, while discrete LEDs connect cathode-to-port for direct segment control.

What is the significance of the "/V" and "+" suffixes in MAX6956ATL/V+?

The "/V" suffix indicates AEC-Q100 automotive qualification, confirming reliability under automotive stress conditions including temperature cycling, ESD, and latch-up testing. The "+" denotes RoHS-compliant, lead-free packaging. Together, MAX6956ATL/V+ meets stringent automotive standards while adhering to environmental regulations - critical for dashboard and powertrain applications.