MAX6955

2-Wire Interfaced, 2.7V to 5.5V LED Display Driver with I/O Expander and Key Scan

2-Wire Interfaced, 2.7V to 5.5V LED Display Drivers with GPIO and Key Scan


Description

The MAX6955 is a compact display driver that interfaces microprocessors to a mix of 7-segment, 14-segment, and 16-segment LED displays through an I2C-compatible 2-wire serial interface. The MAX6955 drives up to 16 digits 7-segment, 8 digits 14-segment, 8 digits 16-segment, or 128 discrete LEDs, while functioning from a supply voltage as low as 2.7V. The driver includes five I/O expander or general-purpose I/O (GPIO) lines, some or all of which can be configured as a key-switch reader. The key-switch reader automatically scans and debounces a matrix of up to 32 switches.

Included on chip are full 14- and 16-segment ASCII 104-character fonts, a hexadecimal font for 7-segment displays, multiplex scan circuitry, anode and cathode drivers, and static RAM that stores each digit. The maximum segment current for the display digits is set using a single external resistor. Digit intensity can be independently adjusted using the 16-step internal digital brightness control. The MAX6955 includes a low-power shutdown mode, a scan-limit register that allows the user to display from 1 to 16 digits, segment blinking (synchronized across multiple drivers, if desired), and a test mode, which forces all LEDs on. The LED drivers are slew-rate limited to reduce EMI.

For an SPI-compatible version, refer to the MAX6954 data sheet. An evaluation kit (EV kit) for the MAX6955 is available.
MAX6955: Functional Diagram MAX6955: Functional Diagram Enlarge+

Key Features

  • Simplifies Driving 5 x 7 Matrix LED Displays
    • Drives Common-Cathode Monocolor and Bicolor LED Displays
    • Drives Up to 16 Digits 7-Segment, 8 Digits 14-Segment, 8 Digits 16-Segment, 128 Discrete LEDs, or a Combination of Digit Types
    • 2.7V to 5.5V Operation
  • Standard 2-Wire Interface Supports a Variety of Microprocessor Architectures
    • 400kbps 2-Wire I2C-Compatible Interface
  • Integrated Flexibility Supports Different Application Requirements
    • Built-In ASCII 104-Character Font for 14-Segment and 16-Segment Digits and Hexadecimal Font for 7-Segment Digits
    • 16-Step Digit-by-Digit Digital Brightness Control
    • Display Blanked on Power-Up
    • Automatic Blinking Control for Each Segment
    • 10µA (typ) Low-Power Shutdown (Data Retained)
  • Five GPIO Port Pins Can Be Configured as Key-Switch Reader to Scan and Debounce Up to 32 Switches with n-Key Rollover
    • IRQ Output when a Key Input Is Debounced
  • Slew-Rate-Limited Segment Drivers for Lower EMI
  • 36-Pin SSOP and 40-Pin DIP and TQFN Packages
  • Automotive Temperature Range Standard Covers Usage in Harsh Environments

Applications/Uses

  • Audio/Video Equipment
  • Bar Graph Displays
  • Panel Meters
  • Set-Top Boxes
  • White Goods
Part Number LCD or LED Digits or Char. Output Format Display Type Interface Fonts Segment Blinking VSUPPLY
(V)
VSUPPLY
(V)
Package/Pins Budgetary
Price
min max See Notes
MAX6955  LED
8-Digit 16-Segment
8-Digit 14-Segment
16-Digit 7-Segment
7 segments
14 segments
16 segments
Common Cathode Serial 2-Wire 400kbit
104 char ASCII
Hexadecimal
Yes 2.7 5.5
SSOP/36
TQFN/40
$9.67 @1k
See All Display Drivers (48)
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.


MAX6955EVKIT: Evaluation Kit for the MAX6955
 

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