herunterladen
3-183
TELCOM SEMICONDUCTOR, INC.
7
6
5
4
3
1
2
8
TC7106
TC7106A
TC7107
TC7107A
Figure 1. TC7106/A/7/A Typical Operating Circuit
AVAILABLE PACKAGES
40-Pin Plastic DIP
40-Pin CERDIP
44-Pin Plastic Quad Flat
Package Formed Leads
44-Pin Plastic Chip
Carrier PLCC
V
REF
+
TC7106/A
TC7107/A
9V
V
REF
33
34
24kΩ
1kΩ
29
36
39 38 40
0.47µF
0.1µF
V
–
1
OSC
3
OSC
2
OSC
TO ANALOG
COMMON (PIN 32)
3 CONVERSIONS/SEC
200mV FULL SCALE
C
OSC
100kΩ
47kΩ
0.22µF
C
REF
–
C
REF
+
V
IN
+
V
IN
–
ANALOG
COMMON
V
INT
V
BUFF
C
AZ
20
21
SEGMENT
DRIVE
2–19
22–25
POL
BP
V
+
MINUS SIGN
BACKPLANE
DRIVE
28
R
OSC
100pF
LCD DISPLAY (TC7106/A) OR
COMMON ANODE LED
DISPLAY (TC7107/A)
27
100mV
1
26
35
V
REF
–
+
31
0.01µF
ANALOG
INPUT
+
–
1MΩ
30
32
ORDERING INFORMATION
PART CODE TC710X X X XXX
6 = LCD
7 = LED
A or blank*
R (reversed pins) or blank (CPL pkg only)
* "A" parts have an improved reference TC
Package Code (see below):
}
Package Temperature
Code Package Pin Layout Range
CKW 44-Pin PQFP Formed Leads 0°C to +70°C
CLW 44-Pin PLCC — 0°C to +70°C
CPL 40-Pin PDIP Normal 0°C to +70°C
IPL 40-Pin PDIP Normal – 25°C to +85°C
IJL 40-Pin CerDIP Normal – 25°C to +85°C
GENERAL DESCRIPTION
The TC7106A and TC7107A 3-1/2 digit direct-display
drive analog-to-digital converters allow existing 7106/7107
based systems to be upgraded. Each device has a preci-
sion reference with a 20ppm/°C max temperature coeffi-
cient. This represents a 4 to 7 times improvement over
similar 3-1/2 digit converters. Existing 7106 and 7107 based
systems may be upgraded without changing external pas-
sive component values. The TC7107A drives common
anode light emitting diode (LED) displays directly with 8mA
per segment. A low-cost, high-resolution indicating meter
requires only a display, four resistors, and four capacitors.
The TC7106A low power drain and 9V battery operation
make it suitable for portable applications.
The TC7106A/TC7107A reduces linearity error to less
than 1 count. Rollover error – the difference in readings for
equal magnitude but opposite polarity input signals – is
below ±1 count. High impedance differential inputs offer
1pA leakage current and a 10
12
Ω input impedance. The
differential reference input allows ratiometric measurements
for ohms or bridge transducer measurements. The
15µV
P–P
noise performance guarantees a “rock solid” read-
ing. The auto-zero cycle guarantees a zero display read-
ing with a zero-volts input.
FEATURES
■ Internal Reference with Low Temperature Drift
TC7106/7 ....................................... 80ppm/°C Typical
TC7106A/7A..................................20ppm/°C Typical
■ Drives LCD (TC7106) or LED (TC7107) Display
Directly
■ Guaranteed Zero Reading With Zero Input
■ Low Noise for Stable Display
■ Auto-Zero Cycle Eliminates Need for Zero
Adjustment
■ True Polarity Indication for Precision Null
Applications
■ Convenient 9 V Battery Operation (TC7106A)
■ High Impedance CMOS Differential Inputs.... 10
12
Ω
■ Differential Reference Inputs Simplify Ratiometric
Measurements
■ Low Power Operation..................................... 10mW
3-1/2 DIGIT A/D CONVERTERS
TC7106/6A/7/7A-7 11/4/96
Verzeichnis
