TC7116
TC7116A
TC7117
TC7117A
3-1/2 Digit Analog-To-Digital Convereters with Hold
FEATURES
GENERAL DESCRIPTION
■ Low Temperature Drift Internal Reference
TC7116/TC7117 ............................ 80 ppm/°C Typ.
TC7116A/TC7117A....................... 20 ppm/°C Typ.
■ Display Hold Function
■ Directly Drives LCD or LED Display
■ Guaranteed Zero Reading With Zero Input
■ Low Noise for Stable
Display .......... 2V or 200mV Full-Scale Range (FSR)
■ Auto-Zero Cycle Eliminates Need for Zero
Adjustment Potentiometer
■ True Polarity Indication for Precision Null
Applications
The TC7116A/TC7117A are 3-1/2 digit CMOS analog-
to-digital converters (ADCs) containing all the active
components necessary to construct a 0.05% resolution
measurement system. Seven-segment decoders, polarity
and digit drivers, voltage reference, and clock circuit are
integrated on-chip. The TC7116A drives liquid crystal
displays (LCDs) and includes a backplane driver. The
TC7117A drives common anode light emitting diode (LED)
displays directly with an 8mA drive current per segment.
These devices incorporate a display hold (HLDR)
function. The displayed reading remains indefinitely, as
long as HLDR is held high. Conversions continue, but
output data display latches are not updated. The reference
low input (VR–EF) is not available as it is with the TC7106/
7107. VR–EF is tied internally to analog common in the
TC7116A/7117A devices.
■ Convenient 9V Battery Operation
(TC7116/TC7116A)
■ High Impedance CMOS Differential Inputs.... 1012Ω
■ Low Power Operation..................................... 10mW
The TC7116A/7117A reduces linearity error to less
than 1 count. Roll-over error (the difference in readings for
equal magnitude but opposite polarity input signals) is
below ±1 count. High-impedance differential inputs offer 1
pA leakage current and a 1012Ω input impedance. The
15µVP-P noise performance guarantees a “rock solid”
reading. The auto-zero cycle guarantees a zero display
reading with a 0V input.
ORDERING INFORMATION
PART CODE
TC711X X XXX
6 = LCD
7 = LED
}
A or blank*
The TC7116A and TC7117A feature a precision, low-
drift internal reference, and are functionally identical to the
TC7116/TC7117. A low-drift external reference is not
normally required with the TC7116A/TC7117A.
* "A" parts have an improved reference TC
Package Code (see below):
Package
Code
Temperature
Range
Package
CKW
CLW
CPL
IJL
44-Pin PQFP
0°C to +70°C
0°C to +70°C
0.1 µF
33
DISPLAY
HOLD
LCD DISPLAY (TC7116/7116A)
OR COMMON ANODE LED
DISPLAY (TC7117/7117A)
44-Pin PLCC
1
34
+
–
C
REF
40-Pin Plastic DIP
40-Pin CerDIP
0°C to +70°C
HLDR
C
REF
1 MΩ
31
SEGMENT
DRIVE
+
2–19
22–25
+
V
– 25°C to +85°C
IN
ANALOG
INPUT
–
0.01 µF
TC7116/A
TC7117/A
20
POL
–
30
32
V
IN
BACKPLANE
DRIVE
MINUS SIGN
21
35
BP/GND
AVAILABLE PACKAGES
ANALOG
COMMON
+
V
40-Pin PDIP
40-Pin CDIP
24 kΩ
28
V
BUFF
+
47 kΩ
9V
36
26
V
REF
0.47 µF
+
V
REF
1 kΩ
C
AZ
100 mV
29
27
0.22 µF
–
V
V
INT
44-Pin PQFP
OSC OSC OSC
2
3
1
TO ANALOG
Formed Leads
COMMON (PIN 32)
C
OSC
39
38
40
3 CONVERSIONS/SEC
R
100 pF
OSC
100 kΩ
44-Pin Plastic Chip
Carrier PLCC
Figure 1. Typical TC7116/A/7/A Operating Circuit
© 2001 Microchip Technology Inc. DS21457A
TC7116/A/7117/A-7 9/17/99