Flexible Display Controller in FPGA for LCD and E-BOOK

Flexible Display Controller in FPGA for LCD and E-BOOK Yvonne Lin – Solutions Manager, Strategic Marketing

Challenges in Consumer Products Design

Consumer Product Challenges 

Cost competitive



Fast time to Market



Low Power Consumption



Small, Compact, Lightweight



Unique Feature set



Portability & Flexibility

Actel Corporation Confidential © 2010

3

Why Displays?

Trend

Actel Corporation Confidential © 2010

5

Trend & Adoption 

LCDs 

Technology matured, many suppliers 







As $ drop, adaptation increased Even price sensitive consumer portables will use LCDs

Major Drawback: Power Consumption

Epaper 

Start of a ramp, E-Book gaining popularity, limited suppliers 

 

Pricing not optimum yet for mass application

Technology advantage for low power application Major Drawback: Color & Refresh time

Actel Corporation Confidential © 2010

6

What is an Display Controller? 

Displays 



Controller 



Graphical output devices made of rows & columns Device used to control and manage the output content

System diagrams Other Video Source

Processor

Display Controller

Memory

Actel Corporation Confidential © 2010

7

Challenges of Display Control 

Processor bandwidth 



Non-standard Displays   



Without built-in LCD controller, constant output to display

Especially for displays less than 10 inches Each Epaper has unique drive requirement Different manufacturers, resolution, BPP, control signals, etc.

Varying requirement on user end 

Custom function, varying video interface & input

Actel Corporation Confidential © 2010

8

Various types & functions of display controller  Application Features 

Advantage



to processor, target flexibility in range Example:specific Qualcomm, TI, Infineon LCD determined

No flexibility, can’t support all LCD types, no processor offload

Drawback

ASSP graphic controller 

Example:Control nVIDIA, Epson LCDRenesas, for that Limited video/processor processor



Limited flexibility & features, may be overkill for simple needs

Feature intensive, target wider range of displays

Main features 

interface and control LCD

FPGAs as graphic controller 

FPGA

Processor

Designed for specific displays in mind Typically in application Pre-determined functions, Usually cheapest way to go ($ wise) processor, single-chip, easy to target, some 



Embeddedbuilt-in with processor controller Standard ASSP

Can implement unique and flexible solution based on user needs, change on the fly User implementation required, hardware designer, knowledge of video and HDL Multiple video and processor interface, custom function, resolution, LVDS display, solve EOL

Most flexible solution for graphic, custom to your application

Target LCD resolution Specific resolution  Example: Actel, Altera, Memory interface Pre-defined

Xilinx

Limited range

Flexible

Pre-defined

Flexible

Power management

Limited

Limited

Flexible

Example suppliers

iMX, PXA, Blackfin

Epson, Renesas, Zoran

Actel, Altera, Xilinx

Actel Corporation Confidential © 2010

9

Benefits of FPGAs as Display Controllers 

Flexibility  



One of a kind implementation  



Design customized logic or algorithms Include additional functions

Processor off-loading  



Quickly designed to meet different display specifications Reprogram with new features, fix

Offload processor intensive tasks into hardware Free up CPU bandwidth to perform other tasks

I/O expansion & Other tasks 

Handling several video sources requires extensive IO ports Actel Corporation Confidential © 2010

10

Sample Applications Using FPGA Display Controller Products

FPGA functions

Why use FPGA

Car entertainment

Mux videos into different LCDs

Custom

Backup camera

Merge various camera source into one

Custom

Cell Phones

Drive LCDs

Flexible, low power

Camera

Extend image to second LCD

Flexible, low power

Hand-held scanner Upgrade to LCD with minimal change

Flexible, low power

Medical device

Used to drive LCDs on handheld tester

No EOL issue

E-Book

Used to drive Epaper

Low power, TTM

Actel Corporation Confidential © 2010

11

Designing a Display Controller in an FPGA

Considerations & Questions to ask 

Functions and features  



Sources  



Will there be external video sources? What will their format be? Frame rate? Resolution?

Output display  



What will the this controller do? Are any additional features required?

What output device will be used? What is the resolution, bits per pixel, refresh rate?

Memory requirement  

Is an external frame buffer required? What kind of memory element makes the most sense & cents?

Actel Corporation Confidential © 2010

13

Typical Block Diagram of an LCD Controller

RAW image data source #1

RAW image data source #2

DSP or MCU

Frame Buffer

Font, image storage

SRAM / SDRAM

Flash

Digital data: RGB, YUV, BT656 etc.

LCD timing data

FPGA

LCD

DSP or MCU Optional off chip buffer

Video Sources / CPU

External Interface

Memory Interface

Display Interface

LCD

Custom Functions FPGA Actel Corporation Confidential © 2010

14

Typical Design Blocks – Display Controller in FPGA 

External interface  



Memory interface 



Frame buffer controller  Partition, read and write image into buffer

Display interface 



Frame grabber  Grabs a frame of input video source Microcontroller interface  Interface to microcontroller

Video Timing Generator  Generates valid timing controls

Custom function 

  

Color conversion  Converts from one color space to another De-interlace  Converts interlaced video into progressive format Scaling  Scales image from one aspect to another Alpha blending  Blends two sources of video into one Actel Corporation Confidential © 2010

15

Same FPGA for LCD and E-PAPER? 

Yes! Different design implemented.



For LCD  



Speed is critical Bandwidth

For EPAPER  

LOW POWER Processor interface

Actel Corporation Confidential © 2010

16

Selecting the right FPGA

FPGA Fundamentals  

A field-programmable gate array (FPGA) is a programmable semiconductor device The characteristics of an FPGA are primarily dictated by the technology used to make it programmable

SRAM

Reprogrammable and volatile

Flash

Reprogrammable and nonvolatile Actel Corporation Confidential © 2010

Antifuse

Nonvolatile

18

Actel’s Low-Power Advantage Larger Density IGLOO 1000x – 1700x lower power consumption than competition

Small Density IGLOO 15x – 25x lower power consumption than competition

Actel Corporation Confidential © 2010

19

IGLOO® nano: Breaking New Ground 

Introducing IGLOO nano FPGAs 

nanoPower 



nanoSize 



–20ºC to 70ºC Zero lead-time

nanoPrice  



package

nanoLead-time 



Industry’s only 3x3 mm

nanoTemp 



As low as 2 µW

50+ devices for under $1 As low as $0.49

Known Good Die program

Actel Corporation Confidential © 2010

20

Summary 

Benefit of a Display controller in an FPGA   



Flexible Customized to your unique application needs Portable design

Choosing the right FPGA is the key  

Actel’s Lowest Power FPGA Find ideal part based on your needs

Actel Corporation Confidential © 2010

21

Questions