3-1/2 DIGIT A/D CONVERTERS
TC7106
TC7106A
TC7107
TC7107A
fewer segments are “ON,” each “ON” output drops more
voltage and current. For the best case of six segments (a
“111” display) to worst case (a “1888” display) the resistor
will change about 230mW, while a circuit without the resistor
will change about 470mW. Therefore, the resistor will re-
duce the effect of display dissipation on reference voltage
drift by about 50%.
The change in LED brightness caused by the resistor is
almost unnoticeable as more segments turn off. If display
brightness remaining steady is very important to the de-
signer, a diode may be used instead of the resistor.
Figure 15. Diode or Resistor Limits Package Power Dissipation
1
APPLICATIONS INFORMATION
Liquid Crystal Display Sources
Several LCD manufacturers supply standard LCD dis-
plays to interface with the TC7106A 3-1/2 digit analog-to-
digital converter.
Manufacturer
Crystaloid
Electronics
AND
2
Part Numbers
1
C5335, H5535,
T5135, SX440
FE 0201,0701
FE 0203, 2201
FE 0501
LD-B709BZ
LD-H7992AZ
3902, 3933, 3903
Address/Phone
5282 Hudson Dr.
Hudson, OH 44236
216/655-2429
720 Palomar Ave.
Sunnyvale, CA 94086
408/523-8200
3415 Kashikawa St.
Torrance, CA 90505
213/534-0360
612 E. Lake St.
Lake Mills, WI 53551
414/648-2361
3
4
5
6
7
APPLICATIONS INFORMATION
+5V
+
1 M
Ω
TP3
IN
–
–5V
Epson
150Ω
24kΩ
1kΩ
100
pF
TP5
100
kΩ
40
TP2
TP1
Hamlin, Inc.
0.01
µF
0.1
µF
0.47
µF
0.22
µF
DISPLAY
Note:
1. Contact LCD manufacturer for full product listing/specifications.
47
kΩ
30
TP
4
Light Emitting Diode Display Sources
21
TC7107A
1
10
20
Several LED manufacturers supply seven segment
digits with and without decimal point annunciators for the
TC7107A.
Manufacturer
Address
640 Page Mill Rd.
Palo Alto, CA 94304
720 Palomar Ave.
Sunnyvale, CA 94086
Display Type
LED
LED
DISPLAY
5.1Ω 1/4W
1N4001
Hewlett-Packard
Components
AND
8
TELCOM SEMICONDUCTOR, INC.
3-197
TELCOM [ TELCOM SEMICONDUCTOR, INC ]
