Add to Signal Chain Designer

ADP5588:  Mobile I/O Expander and QWERTY Keypad Controller

Product Details

The ADP5588 is an I/O port expander and keypad matrix designed for QWERTY type phones that require a large keypad matrix and expanded I/O lines. I/O expander ICs are used in mobile platforms as a solution to the limited number of GPIOs available in the main processor.

In its small 4 mm × 4 mm package, the ADP5588 contains enough power to handle all key scanning and decoding and flag the processor of key presses and releases via the I2C® interface and interrupt. It frees the main microprocessor from having to monitor the keypad, thereby minimizing current drain and increasing processor bandwidth. It is also equipped with a buffer/FIFO and key event counter to handle and keep track of up to 10 unprocessed key or GPI events with overflow wrap and interrupt capability.

The ADP5588 has a keylock capability with an option to trigger or not trigger an interrupt at key presses and releases. All communication to the main processor is done using one interrupt line and two I2C-compatible interface lines. The ADP5588 can be configured to have a keypad matrix of up to 8 rows × 10 columns (a maximum of 80 keys).

When used for smaller keypad matrices, unused row and column pins can be reconfigured to act as general-purpose inputs, outputs, or light sensor inputs. R0, R1, R2, R3, R4, R5, R6, and R7 denote the row pins of the matrix, while C0, C1, C2, C3, C4, C5, C6, C7, C8, and C9 denote the column pins. At power-up, all rows and columns default as GPIs and must be programmed to function as part of the keypad matrix, GPOs, or light sensor inputs. In addition to keypad and GPIO functionalities, C8 and C9 can also be configured as light sensor inputs.

When configured as keypad lines, the function of the C8 and C9 lines is straightforward: the control interface disconnects these lines from the comparator inputs, disables the light sensor comparator, and connects them to the keypad columns of the keypad matrix. When used as light sensor comparator inputs, the control interface disconnects these pins from the keypad, enables the comparators, and connects these lines to the comparator inputs. Two external capacitors (0.1 μF) are required when these pins are configured as light sensor inputs. When used as GPIOs, these pins are removed from the keypad and the light sensor interface, and the light sensor comparators are disabled, along with the logic for the sensors.

  • Keypad and I/O expander designed for QWERTY type phones that require a large keypad matrix


  • 18-GPIO port expander or 10 × 8 keypad matrix
  • GPIOs configurable to GPIs, GPOs, and keypad rows or columns
  • Dual light sensor inputs (C8 and C9)
  • I2C interface
  • I2C register read autoincrement
  • 1.8 V to 3.0 V operation
  • Keypad lock capability
  • Open-drain interrupt output
  • Key press and key release interrupts
  • GPI interrupt with level programmability
  • Programmable pull-ups
  • See data sheet for additional features

ADP5588 Functional Block Diagram


Title Content Type File Type
ADP5588: Mobile I/O Expander and QWERTY Keypad Controller Data Sheet (Rev C, 02/2012) (pdf, 531 kB) Data Sheets PDF
Introduction to ADIsimPower
ADIsimPower is a smart selector and a collection of downloadable tools that produce complete and optimized power designs. Schematic, bill of materials, and performance data are customized to your specific needs in minutes.
Videos HTML
Isolating Power in Communication Bus and Gate Drive Applications
Starting with a communications application overview of small power options through the process of selecting the right power products this webcast is a great resource for your communications applications designs.
Webcasts WEBCAST
Innovative Power Reduction Techniques Enable Handset Manufacturers to Provide Media Rich Devices
The demand for mobile devices with high-end features has been rapidly increasing. Features like text messaging, gaming, GPS navigation, web browsing and video playback on high resolution color displays are becoming the norm in today’s portable consumer electronics market.
(LED Journal, August/September 2009)
Technical Articles HTML
RAQs index Rarely Asked Questions HTML
Glossary of EE Terms Glossary HTML

Design Tools,Models,Drivers & Software

Title Content Type File Type
ADP5588 GPIO Linux Driver Device Drivers HTML
ADP5588 Input Keyboard and GPIO Linux Driver Device Drivers HTML

Evaluation Kits & Symbols & Footprints

Evaluation Boards & KitsView the Evaluation Boards and Kits page for documentation and purchasing

Symbols and Footprints— Analog Devices offers Symbols & Footprints which are compatible with a large set of today’s CAD systems for broader and easier support.

SampleSample & Buy

Price, packaging, availability

Price Table Help

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

ADP5588 Evaluation Board
Model Description Price RoHS View PCN/ PDN Check Inventory/
ADP5588-EVALZ Status: Production Evaluation Board $160.00 Yes -

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.

Check Inventory & Purchase

View Sales and Distribution Offices

content here.
content here.

Review this Product