C328-7640 JPEG Compression VGA Camera Module General Description The C328 JPEG compression module performs as a video camera or a JPEG compressed still camera and can be attached to a wireless or PDA host. Users can send out a snapshot command from the host in order to capture a full resolution single-frame still picture. The picture is then compressed by the JPEG engine and transferred to the host. Block Diagram OV7640 VGA Image Sensor OV528 Compression Engine VCC GND TxD RxD EEPROM (program) Features Low-cost, & low-powered solution for high resolution image capture Built-in down-sampling, clamping and windowing circuits for VGA/CIF/SIF/QCIF/160x128/80x64 image resolutions RS-232: 115.2K bps for transferring JPEG still pictures or 160x128 preview @8bpp with 0.75~6 fps JPEG CODEC for different resolutions Built-in color conversion circuits for 4 gray/16 gray/256 gray/12-bit RGB/16-bit RGB preview images Auto detect baud rate and make connection to the host System Configuration Camera Sensors The C328 uses OmniVision OV7640/8 VGA CameraChips with an 8-bit YCbCr interface. OV528 Serial Bridge The OV528 Serial Bridge is a controller chip that can transfer image data from CameraChips to external device. The OV528 takes 8-bit YCbCr 422 progressive video data from an OV7640 CameraChip. The camera interface synchronizes with input video data and performs down-sampling, clamping and windowing functions with desired resolution, as well as color conversion that is requested by the user through serial bus host commands. The JPEG CODEC with variable quality settings can achieve higher compression ratio & better image quality for various image resolutions. Program Memory A serial type program memory is built-in for C328, which provides user-friendly commands to interface external control units. Pin Description Pin VCC TxD RxD GND Description Power 3.3VDC Data Transmit (3.3V) Data Receive (3.3V) Power Ground VCC TxD RxD GND Electrical Specification VDD = 3.3V+10%, TA = 0 to 25oC Symbol VDD Parameter Condition DC supply voltage Min Typ Max Unit 3.0 3.3 3.6 V Io Normal Operation Current Operating 60 mA Is Suspend Current Suspend 100 uA VIH High level input voltage TTL VIL Low level input voltage TTL 2.0 V 0.8 Lens Specification Description Parameter Imager Format 1/4" F/# 2.8 Focal length (mm) 4.63 Field of View Diagonal (deg) 57 Horizontal (deg) 42 Vertical (deg) 16.5 Distortion -3.3% Relative Illumination 67% Filter Option IR-cut filter included Board Measurement Rev 2 Updated: May 10, 2004 V