Description
●The MAX6956 compact, serial-interfaced LED display driver/I/O expander provide microprocessors with up to 28 ports. Each port is individually user configurable to either a logic input, logic output, or common-anode (CA) LED constant-current segment driver. Each port configured as an LED segment driver behaves as a digitally controlled constant-current sink, with 16 equal current steps from 1.5mA to 24mA. The LED drivers are suitable for both discrete LEDs and CA numeric and alphanumeric LED digits.
●Each port configured as a general-purpose I/O (GPIO) can be either a push-pull logic output capable of sinking 10mA and sourcing 4.5mA, or a Schmitt logic input with optional internal pullup. Seven ports feature configurable transition detection logic, which generates an interrupt upon change of port logic level. The MAX6956 is controlled through an I²C-compatible 2-wire serial interface, and uses four-level logic to allow 16 I²C addresses from only 2 select pins.
●The MAX6956AAX and MAX6956ATL have 28 ports and are available in 36-pin SSOP and 40-pin thin QFN packages, respectively. The MAX6956AAI and MAX6956ANI have 20 ports and are available in 28-pin SSOP and 28-pin DIP packages, respectively.
●For an SPI-interfaced version, refer to the MAX6957 data sheet. For a lower cost pin-compatible port expander without the constant-current LED drive capability, refer to the MAX7300 data sheet.
