4-Wire-Interfaced, 2.5V to 5.5V, 20-Port and 28-Port LED Display Driver and I/O Expander
DescriptionThe MAX6957 compact, serial-interfaced LED display driver general-purpose I/O (GPIO) peripheral provides 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 constantcurrent 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 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 MAX6957 is controlled through an SPI-compatible 4-wire serial interface.
The MAX6957AAX and MAX6957ATL have 28 ports and are available in 36-pin SSOP and 40-pin TQFN (6mm x 6mm) packages, respectively. The MAX6957AAI and MAX6957ANI have 20 ports and are available in 28-pin SSOP and 28-pin DIP packages, respectively.
For a 2-wire interfaced version, refer to the MAX6956 data sheet.
For a lower cost pin-compatible port expander without the constant-current LED drive capability, refer to the MAX7301 data sheet.
- High-Speed 26MHz SPI-/QSPI-™/MICROWIRE®-Compatible Serial Interface
- 2.5V to 5.5V Operation
- -40°C to +125°C Temperature Range
- 20 or 28 I/O Ports, Each Configurable as
- Constant-Current LED Driver
- Push-Pull Logic Output
- Schmitt Logic Input
- Schmitt Logic Input with Internal Pullup
- 11µA (max) Shutdown Current
- 16-Step Individually Programmable Current Control for Each LED
- Logic Transition Detection for Seven I/O Ports
- Bar Graph Displays
- Industrial Controllers
- Panel Meters
- Set-Top Boxes
- System Monitoring
- White Goods
|Part Number||LCD or LED||Digits or Char.||Output Format||Display Type||Interface||VSUPPLY|
|MAX6957||LED||28-Segment||Any digit type||Common Anode||Serial SPI 26Mbit||2.5||5.5|
|See All Display Drivers (45)|
| Pricing Notes: |
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.
Technical DocumentsApp Note 4021 MAX6956 Programming Guide
App Note 2197 Driving LEDs with Constant Current Port Expander Outputs
Tutorial 1883 LEDs Are Still Popular (and Improving) after All These Years
App Note 1879 Using Maxim SPI-compatible Display Drivers with other SPI Peripherals
App Note 1193 Electronic Displays Comparison
App Note 1142 Experimenting with the MAX6956 and MAX6957 SPI and I²C GPIO and LED Display Drivers from a PC
App Note 1141 Adding Global Intensity Control to the MAX6956 and MAX6957 Static LED Drivers
Quality and Environmental DataProduct Reliability Reports: MAX6957.pdf
Lead-Free Package Tin (Sn) Whisker Reports
|Device||Fab Process||Technology||Sample size||Rejects||FIT at 25°C||FIT at 55°C|
- High Integration
- Integrated Watchdog Timer
- Robust and Low EMI
|App Note||4021||MAX6956 Programming Guide|
|App Note||2197||Driving LEDs with Constant Current Port Expander Outputs|
|Tutorial||1883||LEDs Are Still Popular (and Improving) after All These Years|
|App Note||1879||Using Maxim SPI-compatible Display Drivers with other SPI Peripherals|
|App Note||1193||Electronic Displays Comparison|
|App Note||1142||Experimenting with the MAX6956 and MAX6957 SPI and I²C GPIO and LED Display Drivers from a PC|
|App Note||1141||Adding Global Intensity Control to the MAX6956 and MAX6957 Static LED Drivers|