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D026227_08 CR822x Single Board Decoded Scan Engine Integration Guide
4.2 – Electrical System Block Diagram
4.1 – System Requirements
4 - Electrical Specifications
The CR822x is a complete barcode scanning system that can be easily
integrated into any device.
The block diagram below shows the main components of the system.
Power Supply:
The CR822x is powered from the host via the
V
in
and
Gnd pins.
V
in
must be within the range specified in section 4.13 when
measured at the decode board.
V
in
must be maintained with varying
loads, such as when the illumination is turned ON and OFF.
Host Ribbon Cable (FFC):
The impedance of the cable for the USB data
lines should be 90 ohm differential. For 3.3V operation, a ribbon cable of
no more than 6.0” in length can be used with a 0.28 mm [.011”] trace
width and 0.3 mm trace thickness. Longer cables can be used at higher
voltages.
Power Sequencing:
There is no special power sequence needed for the
CR822x as long as the max and min voltage and current specifications
are met. However, if the voltage on a pin is greater than
V
in
, such as when
powering on, then current will flow from the pin to
V
in
through
the pull up resistors.
Thermal Requirements:
The operating temperature range for the CR822x
is -20 ºC to 55 ºC (-4º F to 131 ºF) unenclosed. Special care should be
taken to ensure the temperature at the image sensor does not exceed 70
ºC and the temperature at the processor does not exceed 100 ºC.
DECODE
PCBA
FLEX CABLE
RIBBON CABLE (RS232/USB)
NU = Not Used on USB Model
Power
Illum. Control
TXD/nGoodRead
CTS/USB D+
RTS/NU
PwrDwn
nBeeper
nGoodRead/NU
nWakeUp
nTrigger
RXD/USB D-
GND
V
IN
RS232 Polarit/NU
12C Bus
Image Control
Image Data
OPTICAL
ENGINE
