Introduction
STV0681
1.1.6 “Delete Last” function
An additional user interface function is available in STV0681 with either audio record or playback
hardware fitted. With these, the user can delete the last image or continuous clip to be captured, or
the last audio memo to be recorded. The standard “Clear all” (“CL”) function remains, whether or not
audio hardware is fitted.
1.1.7 Backward compatibility with STV0680B
STV0681 is electrically and functionally compatible with cameras designed for STV0680B, and uses
the same PC/Mac drivers, however the change of device pinout means that some PCB re-design
will be required.
Precise design guidelines are available from ST as a reference design (see Chapter 10). A software
development kit (SDK) for PC is available from ST to interface to the camera and provide the basis
to develop a custom software application for stills and/or video. It includes colour processing
software.
Figure 1: Typical camera system block diagram
LED
Flashgun
Enable/Trigger
Audio
Speaker
2 x 7 seg. LCD
Push
Buttons:
“Shutter
/Record”
Amplifier
“Mode”
CMOS Sensor
VV6411 (CIF)
Microphone
OEM Flashgun
Module
Comparator
VV6501 (VGA)
16MBit or 64MBit
SDRAM
GPIO
LCD
Driver
memory
I/F
Enable/Trigger
Audio DAC
Audio
Pre-Amp
RS232 interface
to PC
RS232
I/F
Transceiver
Sensor data
Sensor
I/F
Circuit (Discretes)
STV0681
Sensor clock
USB
I/F
Detect Low
Battery
Image Array
VReg
Power
Management
Circuit (Discretes)
USB interface
to PC
Piezo
Buzzer
PWM
4.5 - 6v Battery e.g.
3-4 x AA, AAA, etc.
12MHz XTAL
Lens +
IR Filter
Subject
3v3 supply
4-5v (Nominal) supply from Battery or USB
1.2
Key system features
The key features of a typical camera based on the STV0681 chipset are listed here below.
1.2.1 Image features
● Support for CIF resolution sensor - 352 x 288 pixels
● Support for VGA resolution sensor - 640 x 480 pixels
● 80 picture storage capacity possible for CIF, with 64MB memory
● 26 picture storage capacity for VGA, with 64MBit memory
● A greater number of images can be stored when ‘Low’ resolution mode is enabled (e.g. 80 QCIF
images with 16Mbit memory, 107 QVGA images with 64Mbit memory). See Table 1.
● Automatic anti-flicker exposure and gain control
● Support for flashgun.
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ADCS 7283313C
STMICROELECTRONICS [ ST ]
