TC7135 Datasheet, PDF (1/13 Pages) TelCom Semiconductor, Inc – 4-1/2 DIGIT ANALOG-TO-DIGITAL CONVERTER

1
TC7135
4-1/2 DIGIT ANALOG-TO-DIGITAL CONVERTER
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FEATURES
GENERAL DESCRIPTION
s Low Roll-Over Error ......................... ±1 Count Max
s Guaranteed Nonlinearity Error ........ ±1 Count Max
s Guaranteed Zero Reading for 0V Input
s True Polarity Indication at Zero for Null Detection
s Multiplexed BCD Data Output
s TTL-Compatible Outputs
s Differential Input
s Control Signals Permit Interface to UARTs and
µProcessors
s Auto-Ranging Supported With Overrange and
Underrange Signals
s Blinking Display Visually Indicates Overrange
Condition
s Low Input Current ............................................. 1 pA
s Low Zero Reading Drift ............................... 2 µV/°C
s Interfaces to TC7211A (LCD) and TC7212A (LED)
Display Drivers
s Available in DIP and Surface-Mount Packages
The TC7135 4-1/2 digit analog-to-digital converter (ADC)
offers 50 ppm (1 part in 20,000) resolution with a maximum
nonlinearity error of 1 count. An auto-zero cycle reduces zero
error to below 10 µV and zero drift to 0.5 µV/°C. Source
impedance errors are minimized by a 10 pA maximum input
3 current. Roll-over error is limited to ±1 count.
By combining the TC7135 with a TC7211A (LCD) or
TC7212A (LED) driver, a 4-1/2 digit display DVM or DPM can
be constructed. Overrange and underrange signals support
automatic range switching and special display blanking/flash-
ing applications.
Microprocessor-based measurement systems are sup-
ported by BUSY, STROBE, and RUN/HOLD control signals.
Remote data acquisition systems with data transfer via UARTs
are also possible. The additional control pins and multiplexed
4
BCD outputs make the TC7135 the ideal converter for dis-
play or microprocessor-based measurement systems.
ORDERING INFORMATION
Part No.
TC7135CBU
TC7135CLI
TC7135CPI
Package
64-Pin Plastic
Flat Package
28-Pin PLCC
28-Pin Plastic DIP
5 Temperature
Range
0°C to +70°C
0°C to +70°C
0°C to +70°C
TYPICAL 4-1/2 DIGIT DVM WITH LCD
4-1/2 DIGIT LCD
6.8 k Ω
+5V
+5V
TC04
0.1 µF
ANALOG
GROUND
1 µF
0.1
INPUT
µF
100 k Ω
–5V
1
V
28
UR
2
REF IN
27
OR
100 k Ω 3 _ANALOG
0.47 µF
4
COMMON
INT OUT
26
STROBE
25
RUN/HOLD
1 µF 5
AZ IN
24
DGND
6
BUFF OUT
23
POL
100 k Ω
7
8
9
CC+RR– _EEFF
–INPUT
22
CLOCK
21
BUSY
20
D1
10
+INPUT
19
D2
+5V ¹¹ V ⁺
18
D3
12
D5
17
D4
13
B1
TC7135
16
B8
14
B2
B4 ¹⁵
1 16 15 14 12 5 3 4
CD4054A
7 8 13 11 10 9 2 6
120 Hz = 3 READING/SEC
CLOCK IN
1/4 CD4030
CD4081
+5V
SEGMENT
D
R
I
V
BACKPLANE
E
+5V
1
5 BP V+
31 _D1
32 _D2
SEG
33 _D3
OUT
34 _D4
2,3,4
6–26
37–40
30 _B3 TC7211A
29
B2
OSC ³⁶
+5V
28
B1
OPTIONAL
CAP
27 _B0
GND ³⁵
6
7
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TELCOM SEMICONDUCTOR, INC.
TC7135-10 11/6/96
3-113