HP HBCC-0500 Low current bar code digitizer ic Datasheet

H
Low Current Bar Code
Digitizer IC
Technical Data
HBCC-0500
Features
• Compatible with HP Bar
Code Sensors
– HBCC-1570 - 0.013 in.
0.33 mm
- HBCC-1580 - 0.007 in.
0.185 mm
- HBCC-1590 - 0.005 in.
0.13 mm
• Ambient Light Rejection
> 100 K Lux
• Accurate Digitizing of a
Wide Range of Bar Code
Labels
Description
The Hewlett-Packard Low Current
Bar Code Digitizer IC allows
designers to incorporate the high
ambient light rejection and low
power consumption features of
the HBCS-AXXX/TXXX wands
into their own bar code circuitry.
The HBCC-0500 is packaged in a
24 pin SOIC plastic package.
output of different sensor “bins”
is equalized by varying the
amplitude of the LED drive
current.
The sensor output has two components; DC due to ambient light,
and AC from the bar code label.
Photocurrent from the sensor is
amplified and high pass filtered
to remove the ambient light
signal. The AC component is
amplified and sent to an AM
detector to recover the bar code
information. The recovered bar
code signal is low pass filtered to
eliminate the 30 kHz carrier. The
signal is input to a digitizer
consisting of positive and negative
Block Diagram
SENSOR
LED DRIVER
Theory of Operation
The digitizer IC uses the techniques in US Patent 4,682,015 to
reduce power consumption and
sensitivity to ambient light.
Power is reduced by pulsing the
LED every 33 microseconds with
a 1 microsecond pulse. The
5964-1563E
peak detectors and a comparator.
The comparator threshold is
generated from the peak
detectors using a resistor ladder.
This threshold, along with the
current bar code signal, is input
to a comparator. The output of
the comparator drives an external
output transistor.
AM
DETECTOR
AMPLIFIER
HIGH PASS
FILTER
LOW PASS
FILTER
DIGITIZER
AMPLIFIER
OUTPUT
4-33
Sensor Pinout
Pinout
RPER
1
24
LEDD
RPWD
2
23
GND
CTIM
3
22
LPFO
VCC
4
21
LPFI
AGND
5
20
IWSR
EMIN
6
19
CMPO
PREO
7
18
CTHR
VCCA
8
17
CMPI
PPKD
9
16
NPKD
PRBP
10
15
PSTI
PSTB
11
14
CMPA
ACMP
12
13
AMDT
HBCC-0500
Sensor Marking
Sensors are marked with an eight
digit code, the last digit being the
“bin” number. The bin number is
used to determine the bin
resistor, Rb, using the Bin Table.
8
1
7
2
6
3
5
4
TOP VIEW
Function
LED Anode
LED Cathode
Detector Anode
Detector Cathode
Parts List
Pin #
6
2
8
1
Pin Description
Mnemonic
RPER
RPWD
CTIM
VCC
AGND
EMIN
PREO
VCCA
PPKD
PRBP
PSTB
ACMP
AMDT
CMPA
PSTI
NPKD
CMPI
CTHR
CMPO
IWSR
LPFI
LPFO
GND
LEDD
Description
Timer Period
Timer Pulse Width
Timer Capacitor
Filtered Power
Analog Ground
Preamp Emitter Input
Preamp Output
Analog Power
Positive Peak Detector
Preamp Bias Point
Postamp Bypass
Compensation Cap
AM Detector
Compensation Cap
Postamp Input
Negative Peak Detector
Comparator Input
Comparator Threshold
Comparator Output
White State Return Current
Low Pass Filter Input
Low Pass Filter Output
Ground
LED Drive
Bin Table
Bin #
1
2
3
4
5
6
7
4-34
1570, 1580 Rb Ω
8.2
11
15
18
24
30
36
1590 Rb Ω
22
27
36
47
56
75
91
Quantity
1
1
1
1
1
1
2
1
2
2
1
2
1
1
1
2
1
1
1
1
1
2
1
1
4
3
1
Part
Sensor
HBCC-0500
1N4148
2N3904
2N4403
2N5088
39 Ω
9.1 kΩ
20 kΩ
56 kΩ
390 kΩ
470 kΩ
680 kΩ
1.3 MΩ
2.0 MΩ
6.8 MΩ
Bin resistor Rb
12 pF
75 pF
330 pF
680 pF
1.0 nF
2.2 nF
8.2 nF
0.1 µF
0.22 µF
0.47 µF
Optional Parts List
Quantity
1
1
1
2
1
1
1
1
1
Part
1N4148
2N5088
2N3904
10 kΩ
220 kΩ
1.0 MΩ
2.0 MΩ
3.3 nF
1.0 µF
3. A 1.0 µF ceramic cap may be
used in place of the 0.47 µF
cap.
4. Place the 0.22 µF cap attached
to pins 4 and 23 close to the
IC.
5. Use a single point ground close
to pin 23.
Recommended Schematic
Shown is the recommended
schematic for the HBCC-0500.
Here are some construction tips.
1. Place the sensor, 2N4403, bin
resistor, and the 0.47 µF cap
close to each other to minimize
loop area.
2. If the 0.47 µF cap is tantalum,
its ESR must be used in series
with Rb to determine the
correct value for Rb.
Options
There are four options on the
recommended schematic.
1. Output pull up resistor
2. Inverted output
3. Black state return
4. Threshold adjust
Pull Up Resistor
The 10 kΩ pull up resistor on the
standard or inverted output
transistor is optional. If the
transistor is driving a cable, the
resistor should be on the far end
of the cable.
Schematic
+5 V
Rb Ω
2N4403
24 LEDD
+5 V
39 Ω
39 Ω
0.47
µF
0.22
µF
LED ANODE 6
LED CATHODE 2
8.2 nF
DETECTOR
CATHODE 1
8
DETECTOR
ANODE
SENSOR
680 KΩ
10 KΩ (OPTIONAL)
OUTPUT
CMPI 17
0.22
µF
23 GND
LPFO 22
AMDT 13
15
7
6
2N5088
5
470 KΩ
PSTI
21
PREO HBCC- LPFI
0500
EMIN
CMPA 14
ACMP 12
AGND
IWSR 20
1 RPER
V A 8
CC
9.1 KΩ
6.8 MΩ
20 KΩ
56 KΩ
2.2 nF 330 pF
NC
0.22 µF
16
CTHR NPKD
18
470 KΩ
390 KΩ
1N4148
INVERTED OUTPUT
(OPTIONAL)
12 pF
0.1 µF
1 nF
+5 V
10 KΩ
(OPTIONAL)
INVERTED
OUTPUT
680 pF
56 KΩ
0.1 µF
0.1 µF 9
PPKD
2N3904
2.0 MΩ
PRBP 10
PSTB 11
2 RPWD
75 pF 3
CTIM
+5 V
20 KΩ
CMPO 19
4 V
CC
0.1 µF
+5 V
3.3 nF
1.0 MΩ
220 KΩ
2N5088
2.0 MΩ
1.3 MΩ
1.0 pF
1N4148
1 nF
BLACK STATE RETURN
(OPTIONAL)
4-35
Inverted Output
The standard output of the
HBCC-0500 is high when the
sensor is looking at black bars,
and low when the sensor is looking at white spaces. If inverted
output is needed, add the extra
circuitry in the inverted output
block. Make sure that the 10 kΩ
pull up resistor on the normal
output transistor is loaded.
Black State Return
The HBCC-0500 normally returns
to the white state 100 milliseconds after the last transition. The
extra circuitry forces the black
state after a time out period set
by the 1.0 µF cap. The normal
time out period is about 1.5 seconds. If a longer time is needed,
increase the values of the 1.0 µF
and the 3.3 nF caps. The ratio of
values should be no more than
300:1.
its option, replace products that
prove to be defective in material
or workmanship under proper
use during the warranty period.
Threshold Adjustment
NO OTHER WARRANTIES ARE
EXPRESSED OR IMPLIED,
INCLUDING BUT NOT LIMITED
TO THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR
PURPOSE. HEWLETT-PACKARD
IS NOT LIABLE FOR
CONSEQUENTIAL DAMAGES.
The standard circuit uses a
threshold designed for most bar
codes. If the bar codes to be read
consistently have narrow bars
that are lighter than the wide
bars, then the 470 kΩ and the
390 kΩ resistors attached to pin
18 should be swapped.
Warranty and Service
HP Digitizer ICs are warranted
for a period of one year after
purchase covering defects in
material and workmanship.
Hewlett-Packard will repair or, at
Recommended Operating Conditions
Parameter
Scan Velocity
Edge Contrast
VCC
Ambient Temperature
Ambient Light
Min.
7.6 (3)
40
4.5
-20
Max.
76 (30)
6.0
+65
100,000
Units
cm/sec (in/sec)
%
V
°C
Lux
Notes
1
2
3
Notes:
1. Narrow element width = 0.19 mm (0.0075 in.).
2. Contrast is defined as Rw - Rb, where Rw is the reflectance of the spaces in Rb is the
reflectance of the bars, measured at the sensor wavelength (655 or 820 nm). 100%
reflectance is barium sulfate.
3. Power supply ripple and noise should be less than 100 mV peak to peak.
Electrical Characteristics
Parameter
Symbol Typical
Supply Current, IC and Sensor
ICC
2.7
High Level Output Current
IOH
Low Level Output Voltage
VOL
Output Rise Time
tr
4.5
Output Fall Time
tf
0.3
Wake Up Time
tw
50
Max.
4.0
1.0
0.4
20
20
200
Units
mA
µA
V
µs
µs
ms
Notes
4
4
5
Notes:
4. Rise and fall time will be dependent upon the capacitance of the cable.
5. Wake up time is defined as the time from initial power turn on until the circuit is
digitizing bar codes within data sheet limits.
4-36
For additional warranty or service
information, please contact your
local Hewlett-Packard sales
representative or authorized
distributor.
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