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R.ohm LAB-B-2 Nine-Digit Calculator LED Display

Features

These Nine-Digit Calculator Numeric Seven-Segment LED Displays are intended for use under pulsed conditions by enabling the common cathode of each digit sequentially and enabling the desired Segment and Decimal Point anodes in phase with the character enabling pulse. The pulse rate is kept high enough so that light from each character appears to the eye to be constant.

The LAB-B-2 Nine-Digit display assembly uses Chip-on-Board (COB) technology with each character formed by bonding a tiny LED chip integrating both their seven Segment Bars and Decimal Point directly to a printed circuit board (PCB) and both protecting and magnifying them with a one-piece lens.

The leftmost character of the featured display is not populated with the /8 Version.

0.1”/2.54 mm Characters
Seven-Segment Digits with Right-Hand Decimals
Continuous Uniform Segments
Common-Cathode Configuration for Multiplex Applications
0.200”/5.1 mm Character Spacing
Integrated Clear Plastic Lens

Family Members and Applications

Type Products Digits Comments
LAB-B-2/8 Canon LE-83, LE-84  
LAB-B-2/9 Canon LE-85  

 

Genealogy

Type Products Relationship Comments
SK-3-307 Canon LE-83, LE-84 Second Source ANTEX

 

Technical Specifications

Item Min Typ Max Unit Comments
Display
Width
  2.39
60.7
  inch
mm
  
Display
Height
  0.75
19.0
  inch
mm
  
Display
Depth
  0.28
7.2
  inch
mm
 Including Printed Circuit Board,
 without Pins
PCB
Thickness
  0.06
1.6
  inch
mm
 FR4 
Lens
Width
  1.95
49.5
  inch
mm
  
Lens
Height
  0.51
12.9
  inch
mm
  
Lens
Depth
  0.22
5.6
  inch
mm
 
Character
Height
  0.100
2.54
  inch
mm
 At 0.4" / 10 mm Viewing Distance
 w/o lens 0.060" / 1.52 mm
Character
Width
  0.080
2.00
  inch
mm
 w/o Decimal Point
 w/o lens 0.048" / 1.22 mm
Character
Slant Angle
  5.0   degrees   
Character
Spacing
  0.200
5.08
  inch
mm
 

Technology

The displays are formed by bonding monolithic GaAsP (Gallium Arsenide Phosphide) LED chips integrating one character with seven Segment Bars and one Decimal Point, each directly to a double-sided FR4 printed circuit board (PCB) and placing a one-piece clear acrylic magnifying lens with cylindrical shaped surface on top of the assembly with four heat stakes.

The die size of the LED chip is approximately 71 mils * 68 mils / 1.8 mm * 1.7 mm, the magnification of the lens is about 1.7 at a viewing distance of 0.4" / 10 mm.

Packaging

The LAB-B-2 uses a 2.39" / 60.7 mm by 0.75” / 19.0 mm rectangular printed circuit board (PCB) with 17 solder tabs with a 0.1” / 2.54 mm pitch arranged on the bottom of the display module.

Pin Configuration



Pin Pol. Function
1 C Digit 9 (Minus Sign)
2 A C Segments
3 C Digit 8 (MSD)
4 A Decimal Points
5 C Digit 7
6 A A Segments
7 C Digit 6
8 A E Segments
9 C Digit 5
10 A D Segments
11 C Digit 4
12 A G Segments
13 C Digit 3
14 A B Segments
15 C Digit 2
16 A F Segments
17 C Digit 1 (LSD)
The Anode of the Segments A-G and Right-Hand Decimals and the Cathode of the Digits 1-9 are connected to the display in the pictured way. 
horizontal rule

If you have additions to the above datasheet please email: joerg@datamath.org.

© Joerg Woerner, January 10, 2022. No reprints without written permission.