MICROCHIP TC7116A, TC7117, TC7117A Technical data

TC7116/A/TC7117/A

3-1/2 Digit Analog-to-Digital Converters with Hold

Features

• 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

• Zero Reading with Zero Input

• Low Noise for Stable Display

- 2V or 200mV Full Scale Range (FSR)

• Auto-Zero Cycle Eliminates Need for Zero

• AdjustmentPotentiometer

• True Polarity Indication for Precision Null
Applications

• Convenient 9V Battery Operation:
(TC7116/TC7116A)

• High Impedance CMOS Differential Inputs: 10

• Low Power Operation: 10mW

12

Applications

• Thermometry

• Bridge Readouts: StrainGauges, Load Cells,
Null Detectors

• Digital Meters: Voltage/Current/Ohms/Power, pH

• Digital Scales, Process Monitors

• PortableInstrumentation

Device Selection Table

Package Code Package Temperature Range

CPL 40-Pin PDIP 0°Cto+70°C

IJL 40-Pin CERDIP -25°Cto+85°C

CKW 44-Pin PQFP 0°Cto+70°C

CLW 44-Pin PLCC 0°Cto+70°C

General Description

The TC7116A/TC7117A are 3-1/2 digit CMOS analog­to-digital converters (ADCs) containing all the active
componentsnecessarytoconstructa 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 l ow input (V

Ω

TC7106/7107. V
mon in the TC7116A/7117A devices.

The TC7116A/7117A 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
ance. The 15µV
solid” reading. The auto-zero cycle ensuresa zero dis­play reading with a 0V input.

The TC7116A and TC7117A feature a precision, low
drift internal reference, and ar e functionally identical to
the TC7116/TC7117. A low drift external reference is
not normally required with the TC7116A/TC7117A.

-) is not available, as it is with the

REF

-istiedinternallytoanalogcom-

REF

12

Ω input imped-

noise performance enables a “rock

P-P



2002 Microchip TechnologyInc. DS21457B-page 1

TC7116/A/TC7117/A

Package Type

40-Pin PDIP 40-Pin CERDIP

40

OSC1

39

OSC2

38

OSC3

37

TEST

36

35

34

33

32

31

30

29

28

27

26

25

24

23

22

21

+

V

REF

V+

C

+

REF

C

-

REF

COMMON

+

V

IN

-

V

IN

C

AZ

V

BUFF

V

INT

V-

G

2

C

3

100's

A

3

G

3

BP/GND

(TC7116/7117)
(TC7116A/TC7117A)

1's

10's

100's

1000's

(Minus Sign)

HLDR

D

C

B

A

F

G

E

D

C

B

A

F

E

D

B

F

E

AB

POL

1

2

1

3

1

4

1

5

1

6

1

7

1

8

1

TC7116CPL

9

TC7116ACPL

2

TC7117CPL

10

2

TC7117ACPL

11

2

12

2

13

2

14

2

15

3

16

3

17

3

18

3

19

4

20

1's

10's

100's

1000's

(Minus Sign)

HLDR

D

C

B

A

F

G

E

D

C

B

A

F

E

D

B

F

E

AB

POL

1

2

1

3

1

4

1

5

1

6

1
1

7

8

1

9

2

10

2

11

2

12

2

13

2

14

2

15

3

16

3

17

3

18

3

19

4

20

TC7116IJL

TC7116AIJL

TC7117IJL

TC7117AIJL

40

OSC1

39

OSC2

38

OSC3

37

TEST

36

35

34

33

32

31

30

29

28

27

26

25

24

23

22

21

+

V

REF

V+

C

+

REF

-

C

REF

COMMON

+

V

IN

-

V

IN

C

AZ

V

BUFF

V

INT

V-

G

2

C

3

100's

A

3

G

3

BP/GND

(TC7116/7117)
(TC7116A/TC7117A)

44-Pin PLCC 44-Pin PQFP

+

+

1

A

6543 1442

F

7

1

G

8

1

E

9

1

D

10

2

C

11

2

12

NC

B2

13

A

2

F

2

E

2

D

3

18 19 20 21 23 24

3

B

Note 1: NC = No internal connection.

2: Pins 9, 25, 40 and 56 are connected to the die substrate. Thepotential at thesepins is approximately V+. No external

connections should be made.

1

B1C1D

TC7116CLW

TC7116ACLW

TC7117CLW

TC7117ACLW

4

3

3

F

E

AB

22

HLDR

NC

NC

POL

OSC1

OSC242OSC341TEST40V

43

25 26 27 28

3A3C3G2

G

BP/

GND

REF

39

38

37

36

35

34

33

3214

3115

3016

2917

V+

C

+

REF

-

C

REF

COMMON

VIN+

NC

V

-

IN

C

AZ

V

BUFF

V

INT

V-

NC

NC

TEST

OSC3

NC

OSC2

OSC1

HLDR

D

C

B

+

REF

V

44 43 42 41 39 3840

1

2

3

4

5

6

7

8

9

1

10

1

11

1

12 13 14 15 17 18

1F1G1E1

A

-

REF

REF

V+

C

C

TC7116CKW

TC7116ACKW

TC7117CKW

TC7117ACKW

16

+

-

IN

IN

COMMON

V

V

2B2A2F2E2

D2C

AZ

BUFF

C

V

37

36

35

19 20 21 22

V

INT

34

V-

33

NC

32

G

3

C

31

3

30

A

3

29

G

3

BP/

28

GND

27

POL

26

AB

4

E

25

3

F

24

3

23

B

3

3

D

DS21457B-page 2



2002 Microchip TechnologyInc.

Typical Application

TC7116/A/TC7117/A

TC7116/A
TC7117/A

+

Analog

Input

–

1MΩ

0.01µF

47kΩ

0.22µF

0.47µF

34

31

V

30

V

ANALOG

32

COMMON

28

V

C

29

27

V

OSC2

39 38

0.1µF

REF

+

IN

-

IN

BUFF

AZ

INT

R

100kΩ

+

OSC

33

C

REF

100pF

Display
Hold

HLDR

-C

2–19

22–25

POL

BP/GND

V

REF

OSC1OSC3

C

OSC

LCD Display (TC7116/7116A)

1

V+

+

V-

40

3 Conversions Per Second

or Common Anode LED Display

(TC7117/7117A)

Segment
Drive

20

Minus Sign

21

35

24kΩ

V

36

REF

100mV

26

1kΩ

To Analog
Common (Pin 32)

Backplane Drive

+

9V



2002 Microchip TechnologyInc. DS21457B-page 3

TC7116/A/TC7117/A

1.0 ELECTRICAL
CHARACTERISTICS

Absolute Maximum Ratings*

Supply Voltage:

TC7116/TC7116A (V+ to V-) ...........................15V

TC7117/TC7117A (V+ to GND).......................+6V

V- to GND.........................................................-9V

Analog Input Voltage(Either Input) (Note 1)... V+ to V-

Reference Input Voltage (Either Input)............V+ to V-

Clock Input:

TC7116/TC7116A............................... TEST to V+

TC7117/TC7117A.................................GND to V+

Package Power Dissipation;T

40-Pin CDIP ................................................2.29W

40-Pin PDIP ................................................1.23W

44-Pin PLCC ...............................................1.23W

44-Pin PQFP...............................................1.00W

Operating Temperature:

C (Commercial) Device ................... 0°C to +70°C

I (Commercial) Device.................... 0°C to +70°C

Storage Temperature..........................-65°C to +150°C

≤ 70°C (Note 2)

A

*Stresses above those listed under "Absolute Maximum
Ratings" may cause permanent damage to the device. These
are stress ratings only and functional operation of the device
at these or any other conditions above those indicated in the
operation sections of the specifications is not implied.
Exposure to Absolute Maximum Rating conditions for
extended periods may affectdevice reliability.

TC7116/A AND TC7117/A ELECTRICAL SPECIFICATIONS

Electrical Characteristics: Unless otherwise noted, specifications apply to both the TC7116/A and TC7117/A at TA=25°C,

f

= 48kHz. Partsare testedin the circuitof the Typical Operating Circuit.

CLOCK

Symbol Parameter Min Typ Max Unit Test Conditions

Z

IR

R/O RolloverError(DifferenceinReading f or

CMRR Common Mode Rejection Ra ti o

e

N

I

L

Note 1: Inputvoltages may exceed the supply voltages providedtheinputcurrent is limited to ±100µA.

Zero Input Reading — ±0 — Digital

Ratiometric Reading 999 999/1000 1000 Digital

-1 ±0.2 +1 Counts V
Equal Positive and Negative
Readings Near Full Scale)

Linearity (MaximumDeviation fromBest
Straight Line Fit)

(Note 3)

Noise (Peak to Peak 95% of Time) — 15 — µVVIN=0V

Leakage Current at Input — 1 10 pA VIN=0V
Zero Reading Drift — 0.2 1 µV/°C V

2: Dissipationratingassumes device is mounted with all leads solderedtoprinted circuit board.
3: Refer to “Differential Input” discussion.
4: Backplane drive is in phasewithsegment drive for “OFF” segment,180°out of phase for “ON” segment. Frequency is

20 times conversion rate. Average DC component is less than 50mV.

5: The TC7116/TC7116A logicinputs have aninternal pull-down resistor connectedfrom HLDR, Pin 1 to TEST, Pin 37.The

TC7117/TC7117A logic inputs have an internal pull-down resistor connected from HLDR, Pin 1 to GND, Pin 21.

-1 ±0.2 +1 Counts Full Scale = 200mV or 2V

—50—µV/V V

—1.02µV/°C “I”Device=-25°Cto+85°C

Reading

Reading

VIN=0V
Full Scale= 200mV

V

IN=VREF

V

=100mV

REF

-=+VIN+ ≅ 200mV

IN

or ≈ 2V

=±1V,VIN=0V

CM

Full Scale= 200mV

Full Scale= 200mV

=0V

IN

“C” Device= 0°C to +70°C

DS21457B-page 4



2002 Microchip TechnologyInc.

TC7116/A/TC7117/A

TC7116/A AND TC7117/A ELECTRICAL SPECIFICATIONS (CONTINUED)

Electrical Characteristics: Unless otherwise noted, specifications apply to both the TC7116/A and TC7117/A at TA= 25°C,

f

= 48kHz. Partsare testedin the circuitof the Typical Operating Circuit.

CLOCK

Symbol Parameter Min Typ Max Unit Test Conditions

TC

I

DD

V

C

V

CTC

V

SD

V

BD

Note 1: Inputvoltages may exceed the supply voltages providedtheinputcurrent is limited to ±100µA.

Scale FactorTemperatureCoefficient — 1 5 ppm/°C VIN=199mV,

SF

“C” Device= 0°C to +70°C
(Ext. Ref = 0ppm°C)

— — 20 ppm/°C “I” Device = -25°C to + 85°C

Input Resistance,Pin 1 30 70 — kΩ (Note 5)

Pin 1 — — Test + 1.5 V TC7116/A Only

V

IL,

Pin 1 — — GND + 1.5 V TC7117/A Only

V

IL,

Pin 1 V+- 1.5 — — V Both

V

IH,

SupplyCurrent (Does not Include LED

—0.81.8mAV

IN

=0V

Current for TC7117/A)
AnalogCommonVoltage

(with Respectto PositiveSupply)
T emperature Coefficient of Analog

Common (with Respectto Positive
Supply)

TC7116/TC7117A ONLYPeakto Peak
SegmentDriveVoltage

TC7116A/TC7116AONLY Peakto Peak
Backplane Drive Voltage

TC7117/TC7117A ONLY
SegmentSinking Current

2.4 3.05 3.35 V 25kΩ BetweenCommon
and Positive Supply

“C” Device: 0°C to +70°C

——

20
80

—
50
—

—
ppm/°C
ppm/°C

TC7116A/TC7117A
TC7116/TC7117

456VV+toV-=9V

(Note 4)

456VV+toV-=9V

(Note 4)

5 8 — mA V+=5.0V

Segment Voltage = 3V

(Except Pin 19)
TC7117/TC7117A ONLY

SegmentSinking Current (Pin19 Only)

10 16 — mA V+=5.0V

Segment Voltage = 3V

2: Dissipationratingassumes device is mounted with all leads solderedtoprinted circuit board.
3: Refer to “Differential Input” discussion.
4: Backplane drive is in phasewithsegment drive for “OFF” segment,180°out of phase for “ON” segment. Frequency is

20 times conversion rate. Average DC component is less than 50mV.

5: The TC7116/TC7116A logicinputs have aninternal pull-down resistor connectedfrom HLDR, Pin 1 to TEST, Pin 37.The

TC7117/TC7117A logic inputs have an internal pull-down resistor connected from HLDR, Pin 1 to GND, Pin 21.



2002 Microchip TechnologyInc. DS21457B-page 5

TC7116/A/TC7117/A

2.0 PIN DESCRIPTIONS

The descriptions of the pins are listed in Table 2-1.

TABLE 2-1: PIN FUNCTION TABLE

Pin Number

(40-Pin PDIP)

(40-Pin CERDIP)

1 8 HLDR Hold pin, Logic 1 holdspresent display reading.
29D
310C
411B
512A
613F
714G
815E
916D

10 17 C

11 18 B
12 19 A
13 20 F
14 21 E
15 22 D
16 23 B
17 24 F
18 25 E
19 26 AB
20 27 POL Activates the negative polarity display.
21 28 BP/

22 29 G
23 30 A
24 31 C
25 32 G
26 34 V- Negative power supply voltage.
27 35 V

28 36 V

29 37 C

30 38 V
31 39 V
32 40 COMMON This pin is primarilyusedto set the Analog Common mode voltagefor battery

33 41 C
34 42 C

Pin Number

(44-Pin PQFP)

Symbol Description

1
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3

4

GND

3
3
3
2

INT

BUFF

AZ

- The analog LOW input is connectedto this pin.

IN

+ The analog HIGH input signalis connected to this pin.

IN

-SeePin34.

REF

+A0.1µF capacitor is used in most applications. If a large Common mode voltage

REF

Activates the D section of the units display.
Activates the C section of the units display.
Activates the B section of the units display.
Activates the A section of the units display.
Activates the F section of the unitsdisplay.
Activates the G section of the unitsdisplay.
Activates the E section of the units display.
Activates the D section of the t ens display.
Activates the C section of the t ens display.
Activates the B section of the tens display.
Activates the A section of the tens display.
Activates the F section of the tensdisplay.
Activates the E section of the tens display.
Activates the D section of thehundreds display.
Activates the B section of the hundreds display.
Activates the F section of the hundreds display.
Activates the E section of the hundreds display.
Activates both halves of the 1 in the thousands display.

LCD backplane drive output (TC7116/TC7116A).Digital ground
(TC7117/TC7117A).

Activates the G section of the hundreds display.
Activates the A section of the hundreds display.
Activates the C section of thehundreds display.
Activates the G section of thetensdisplay.

Integrator output. Connection point for integration capacitor.
See Section4.3, IntegratingCapacitorfor more details.

Integration resistor connection. Use a 47kΩ resistor for a 200mV full scale range
and a 470kΩ resistorfor 2V full scale range.

The size of the auto-zerocapacitorinfluences systemnoise. Use a 0.47µF
capacitor for 200mV full scale, and a 0.047µF capacitor for 2V full scale.
See Section4.1,Auto-Zero Capacitor for more details.

operation,orinsystems wheretheinput signalisreferencedtothepower supply.
It also acts as a reference voltage source. See Section3.1.6,Analog Common
for more details.

exists (for example,the V
used, a 1µF capacitoris recommended and will hold the rollover errorto

- pin is not at analog common),anda 200mV scaleis

IN

0.5 count.

DS21457B-page 6



2002 Microchip TechnologyInc.

TABLE 2-1: PIN FUNCTION TABLE (CONTINUED)

Pin Number

(40-Pin PDIP)

(40-Pin CERDIP)

35 43 V+ Positive Power SupplyVoltage.
36 44 V

37 3 TEST Lamp test. When pulled HIGH (to V+), all segments will be turned on and the dis-

38 4 OSC3 See Pin 40.
39 6 OSC2 See Pin 40.
40 7 OSC1 Pins 40, 39, 38 make up the oscillator section. For a 48kHz clock (3 readings per

Pin Number

(44-Pin PQFP)

Symbol Description

+ The analog input required to generate a full scale output (1999 counts). Place

REF

100mVbetween Pins 32 and 36 for 199.9mV full scale. Place 1V between
Pins 35 and 36 for 2V full scale.See Section 4.6, ReferenceVoltage.

play should read -1888. It may also be used as a negative supply for externally
generated decimal points. See Section 3.1.7, TEST for additional information.

section), connect Pin 40 to the junction of a 100kΩ resistor and a 100pF capaci­tor. The 100kΩ resistoris tied to Pin 39 andthe 100pF capacitor is tied to Pin 38.

TC7116/A/TC7117/A

3.0 DETAILED DESCRIPTION

(All Pin Designations Refer to 40-Pin PDIP.)

3.1 Analog Section

Figure 3-1 shows the block diagram of the analog sec­tion for the TC7116/TC7116A and TC7117/TC7117A.
Each measurement cycle is divided into three phases:
(1) Auto-Zero (AZ), (2) Signal Integrate (INT), and
(3) Reference Integrate (REF), or De-integrate (DE).

3.1.1 AUTO-ZERO PHASE

Highand low inputsaredisconnected from the pins and
internally shorted to analog common. The reference
capacitor is charged to the reference voltage. A feed­back loop is closed around the system to charge t he
auto-zerocapacitor (C
ages in the buffer amplifier, integrator,and comparator.
Since the comparator is included in the loop, AZ accu­racy is limited only by systemnoise.The offsetreferred
to the input is less than 10µV.

) to compensate for offset volt-

AZ

3.1.2 SIGNAL INTEGRATE PHASE

The auto-zero loop is opened, the internal short is
removed, and the internal high and low inputs are con­nected to the external pins. The converter then inte­grates the differential voltages between V
for a fixed time. This differential voltage can be within a
wide Common mode range: 1V of either supply. How­ever,i f the input signal has no returnwith respectto the
converter power supply, V

- can be tied to analog

IN

common to establish the correct Common m ode volt­age. At the end of this phase, the polarity of the
integrated signal is determined.

+ and VIN-

IN



2002 Microchip TechnologyInc. DS21457B-page 7