Hand Held Products IT4000, Руководство по интеграции

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1 - 4 IMAGETEAM™ 4X00 Series Integration Manual
Electrical Interface Considerations
When designing the host system circuitry with a switched V
In
imager, you must make sure there is no leakage path from the host
into the imager I/O lines. Leakage back into the imager I/O causes the imager V
In
to be back powered via the imager’s internal
pull-ups, protection diodes, and parasitic FET diodes. This results in unwanted current draw and causes the imager's power up
reset system to fail. A power up reset failure causes the imager to behave erratically and it may not respond correctly to I
2
C
commands.
11 Vin LED +3V to +9V - Power supply input for LED illumination and aiming.
12 D0 Output - Pixel data. Data lines change on each falling edge of pixel clock. Data is considered valid on
the rising edge of pixel clock.
13 Vin Imager Vin Imager, +3.3V - Power supply for the imager. Care must be taken to ensure this supply is heavily
decoupled and is protected from cross coupling to high frequency signals of the processing/decoding cir-
cuitry. A broad band filter may be needed to obtain adequate isolation. See
Considerations and Methods
for the Power Supply on page C-1.
When designing the host system circuitry with a switched V
In
imager, you must guarantee there is no
leakage path from the host into the imager I/O lines. Leakage back into the imager I/O causes the
imager V
In
to be back powered via the imager’s internal pull-ups, protection diodes, and parasitic FET
diodes. This results in unwanted current draw and the imager's power up reset system will fail. The
imager behaves erratically and may not respond correctly to I2C commands when there is a power up
reset failure.
14 D1
Output - Pixel data. Data lines change on each falling edge of pixel clock. Data is considered valid on
the rising edge of pixel clock.
15 D2
16 D3
17 D4
18 D5
19 D6
20 D7
21 Pixel Clock (PCLK) Output - Imager timing signal that clocks pixel data. Data is valid on the rising edge of this signal.
Pin Signal Description