The MAX6956 is a multi-function LED display driver/I/O expander from Texas Instruments that has 28 ports that can be individually configured as logic inputs, logic outputs, or common-anode (CA) LED constant-current segment drivers.
The MAX6956 is a compact, serial‑interfaced LED display driver and I/O expander that provides up to 28 configurable ports. Each port can operate as a constant‑current LED segment driver, a push‑pull logic output, or a Schmitt‑trigger logic input, with optional internal pull‑up resistors. Seven ports include transition‑detection logic that can generate an interrupt on level changes.
The device is controlled via an I²C‑compatible 2‑wire interface supporting up to 400 kbps and offers a wide operating voltage range (2.5 V to 5.5 V) and temperature range (‑40 °C to +125 °C). Various package options are available, including 36‑pin SSOP, 40‑pin thin QFN, 28‑pin SSOP, and 28‑pin DIP, allowing flexibility for different board layouts.
| Operating Supply Voltage | 2.5 V to 5.5 V |
|---|---|
| Number of I/O Ports | 20 or 28 ports |
| LED Current Steps | 16 steps from 1.5 mA to 24 mA |
| Shutdown Current | 11 pA (max) |
| Operating Temperature Range | -40 °C to +125 °C |
| I²C Interface Speed | 400 kbps |
| Package Options | 36‑pin SSOP, 40‑pin thin QFN, 28‑pin SSOP, 28‑pin DIP |
The MAX6956 operates from 2.5 V to 5.5 V.
It provides either 20 or 28 configurable ports depending on the package.
The driver offers 16 programmable current steps ranging from 1.5 mA to 24 mA per segment.
Shutdown mode is entered by setting the S bit in the configuration register; all ports become inputs and pull‑up currents are turned off.