TC811 Datasheet, PDF (1/12 Pages) TelCom Semiconductor, Inc – 3-1/2 DIGIT A/D CONVERTER WITH HOLD AND DIFFERENTIAL REFERENCE INPUTS

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TC811
3-1/2 DIGIT A/D CONVERTER WITH HOLD AND DIFFERENTIAL
REFERENCE INPUTS
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FEATURES
TYPICAL APPLICATIONS
s Differential Reference Input
s Display Hold Function
s Fast Over-Range Recovery, Guaranteed Next
Reading Accuracy
s Low Temperature Drift Internal
Reference ....................................... 35ppm/°C (Typ)
s Guaranteed Zero Reading With Zero Input
s Low Noise ..................................................... 15µV_p-p
s High Resolution (0.05%) and Wide Dynamic
Range (72 dB)
s High Impedance Differential Input
s Low Input Leakage Current ....................... 1pA Typ
10pA Max
s Direct LCD Drive – No External Components
s Precision Null Detection with True Polarity at Zero
s Crystal Clock Oscillator
s Available in DIP, Compact Flat Package or PLCC
s Convenient 9V Battery Operation with
Low Power Dissipation (600µA Typical, 1mW
Maximum)
FUNCTIONAL BLOCK DIAGRAM
s Thermometry
s Digital Meters
— Voltage/Current/Power
— pH Measurement
— Capacitance/Inductance
— Fluid Flow Rate/Viscosity
3
— Humidity
— Position
s Panel Meters
s LVDT Indicators
s Portable Instrumentation
s Digital Scales
s Process Monitors
s Gaussometers
4
s Photometers
ORDERING INFORMATION
Part No. Package
Temp.
Range
Max V_REF
Tempco
5 ^{TC811CKW 44-PQFP}
0°C to +70°C 75 ppm/°C
TC811CPL 40-Pin Plastic DIP 0°C to +70°C 75 ppm/°C
TC811CPL
C
+
REF
CREF
VR+EF
VR–EF
35 36
33
RINT
C
–
REF
VBUFF
V+
34
28 38
10
µA
V
+
IN
31
INT
A/Z
ANALOG ³²
COMMON
V
–
IN
30
INT
ZI & A/Z
ZI &
A/Z
–
+
ZI
DE DE
(–) (+)
DE (+) DE (–)
AZ & DE (±)
–
+
V+– 3.0V
26
V–
LOW
TEMPCO
VREF
TYPICAL SEGMENT OUTPUT
V+
0.5mA
2mA
SEGMENT
OUTPUT
LCD DISPLAY
INTERNAL DIGITAL GROUND
BACKPLANE
21
CAZ
CINT
VINT
29
27
INTEGRATOR
–
+
+
–
A/Z
TO
DIGITAL
SECTION
LCD SEGMENT DRIVERS
7 SEGMENT 7 SEGMENT 7 SEGMENT
DECODE
DECODE
DECODE
200
DATA LATCH
COMPARATOR
THOUSANDS HUNDREDS
TENS
UNITS
TO SWITCH DRIVERS
FROM COMPARATOR OUTPUT
CLOCK
fOSC
4
≈70kΩ
CONTROL LOGIC
40
OSC ₁
39
22MΩ
OSC2
INTERNAL DIGITAL GOUND _VTH
= 1V
1
HLDR
38 _V+
6.2V
500Ω
TEST
26 _V–
TELCOM SEMICONDUCTOR, INC.
10pF
V+
470k
20pF
V+
kH
TC811-7 11/5/96
3-137
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