1. Presenter：梁正勳 Number:97662003
SoC Design of An Auto-Focus Driving Image Signal Processor for Mobile Camera Applications
Presenter：梁正勳
Number:
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

2. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Outline
Introduction
Auto Focus Camera System
SoC Implementation
Experimental Results
Conclusions
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

3. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Index Terms
Image Signal Processor (ISP)
Auto Focus(AF)
Camera system
Voice Coil Motor (VCM)
AF lens driver
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

4. AF mobile phone camera system
(b) The proposed AF camera configuration
(a) A conventional AF camera configuration
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

5. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Auto Focus (AF) Theory
(a) The focusing mechanism
(b) The focusing algorithm
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

6. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
AF lens driver and Lens
Lens type
Driver type
Factors
Power consumption
AF speed
Module Size
Cost
Stepping motor
H-bridge
High
Slow
Big
VCM
DAC
Medium
Small
Low
Piezo motor
Fast
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

7. AF Control Block (AF filter & MCU)
AF block diagram
AF control flow
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

8. A detailed VCM lens module
(a) AF camera module
(b) Focus values
(c) AF lens driver outputs
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

9. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
AF lens driver
Architecture of AF lens driver
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

10. Shows the architecture
Buffer Amplifier
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

11. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Chip Design
(a) The AF camera module
using the AF_ISP
(b) The die photo of
the AF_ISP
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

12. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Experimental Results
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

13. The results of comparison against other
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

14. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Experimental Results
(a) defocused image
(b) focused image
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

15. (d) The measured output voltage (c) the measured focus values
Experimental Results
(d) The measured output voltage
of the AF (VCM) driver
(c) the measured focus values
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

16. VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C
Conclusions
This paper describes an auto-focus driving image signal processor and the AF solution with it.
Phone manufacturers are becoming more cost effective and low power consumption.
We developed the SoC of an AF driving ISP which has all-in-one AF solution, such as AF statistics, AF control and AF lens driver.
In addition, this SoC solution also allows for fast and optimal AF performance of mobile camera applications.
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C

17. Thank you for your attentions !
The End
Thank you for your attentions !
VLSI.Lab.,National Changhua University of Education,Taiwan,R.O.C