TelCom Semiconductor Inc TC7107CPL, TC7107ARIJL, TC7107ARIPL, TC7107ARCPL, TC7107ARCLW Datasheet

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 preci­sion reference with a 20ppm/°C max temperature coeffi­cient. 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 pas­sive 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 1012Ω 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” read­ing. The auto-zero cycle guarantees a zero display read­ing 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.... 1012Ω

■ 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

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ELECTRICAL CHARACTERISTICS (Note 3)

TC7106/A & TC7107/A

Parameters Test Conditions Min Typ Max Unit

Zero Input Reading VIN = 0.0 V – 000.0 ±000.0 +000.0 Digital

Full-Scale = 200.0mV Reading

Ratiometric Reading VIN = V

REF

999 999/1000 1000 Digital

V

REF

= 100 mV Reading

Roll-Over Error (Difference in V

–
IN

= +V

+
IN

≅ 200mV – 1 ±0.2 +1 Counts
Reading for Equal Positive and
Negative Reading Near Full-Scale)

Linearity (Max. Deviation From Full-Scale = 200mV – 1 ±0.2 +1 Counts
Best Straight Line Fit) or Full-Scale = 2.000 V

Common-Mode V

CM

= ±1V, VIN = 0V, — 50 — µV/V

Rejection Ratio (Note 4) Full Scale = 200.0 mV
Noise (Pk – Pk Value Not V

IN

= 0 V — 15 — µV

Exceeded 95% of Time) Full-Scale = 200.0mV
Leakage Current @ Input VIN = 0 V — 1 10 pA
Zero Reading Drift VIN = 0 V

“C” Device = 0°C to +70°C — 0.2 1 µV/°C
VIN = 0 V
“I” Device = – 25°C to +85°C — 1.0 2 µV/°C

Scale Factor VIN = 199.0mV,
Temperature Coefficient “C” Device = 0°C to +70°C — 1 5 ppm/°C

(Ext. Ref = 0ppm°C)
V

IN

= 199.0mV — — 20 ppm/°C

“I” Device = – 25°C to +85°C

Supply Current (Does Not VIN = 0 — 0.8 1.8 mA
Include LED Current For TC7107/A)

ABSOLUTE MAXIMUM RATINGS*
TC7106A

Supply Voltage (V+ to V–)...........................................15 V

Analog Input Voltage (either input) (Note 1)......... V+ to V

–

Reference Input Voltage (either input) ................. V+ to V

–

Clock Input ........................................................ Test to V

+

Package Power Dissipation (Note 2) (TA ≤ 70°C)

CerDIP..............................................................2.29W

Plastic DIP ........................................................1.23W

PLCC ................................................................1.23W

PQFP................................................................1.00W

Operating Temperature

“C” Devices............................................ 0°C to +70°C

“I” Devices ........................................– 25°C to +85°C

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

Lead Temperature (Soldering, 60 sec) ...................300°C

TC7107A

Supply Voltage

V

+

................................................................................................ +6 V

V

–

............................................................................................... – 9 V

Analog Input Voltage (either input) (Note 1)......... V+ to V

–

Reference Input Voltage (either input) ................. V+ to V

–

Clock Input ....................................................... GND to V

+

Power Dissipation (Note 2) (TA ≤ 70°C)

40-Pin CerDIP Package ...................................2.29W

40-Pin Plastic DIP.............................................1.23W

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

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

Operating Temperature

“C” Devices............................................ 0°C to +70°C

“I” Devices ........................................– 25°C to +85°C

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

Lead Temperature (Soldering, 10 sec) .................+300°C

*Static-sensitive device. Unused devices must be stored in conductive
material. Protect devices from static discharge and static fields. 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 operational sections of the specifications is not implied.
Exposure to Absolute Maximum Rating Conditions for extended periods
may affect device reliability.

TC7106
TC7106A
TC7107
TC7107A

3-1/2 DIGIT A/D CONVERTERS

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7

6

5

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ELECTRICAL CHARACTERISTICS (Cont.) (Note 3)

TC7106/A & TC7107/A

Parameters Test Conditions Min Typ Max Unit

Analog Common Voltage 25kΩ Between Common 2.7 3.05 3.35 V
(With Respect to Pos. Supply) and Pos. Supply

Temp. Coeff. of 25kΩ Between Common
Analog Common and Pos. Supply
(With Respect 0°C ≤ TA ≤ +70°C 7106A/7A 20 50 ppm/°C
to Pos. Supply) ("C", Commercial Temp. Range Devices) 7106/7 80 — ppm/°C

Temp. Coeff. of 25kΩ Between Common
Analog Common and Pos. Supply
(With Respect – 25°C ≤ T

A

≤ 85°C — — 75 ppm/°C

to Pos. Supply) (“I,” Industrial Temp. Range Devices)
TC7106A ONLY Pk – Pk V

+

to V– = 9V 4 5 6 V

Segment Drive Voltage (Note 5)
TC7106A ONLY Pk – Pk V+ to V– = 9V 4 5 6 V

Backplane Drive Voltage (Note 5)
TC7107A ONLY V+ = 5.0V 5 8.0 — mA

Segment Sinking Current (Except Pin 19) Segment Voltage = 3V
TC7107A ONLY V+ = 5.0V 10 16 — mA

Segment Sinking Current (Pin 19) Segment Voltage = 3V

NOTES: 1. Input voltages may exceed the supply voltages provided the input current is limited to ±100µA.

2. Dissipation rating assumes device is mounted with all leads soldered to printed circuit board.

3. Unless otherwise noted, specifications apply to both the TC7106/A and TC7107/A at TA = 25°C, f

CLOCK

= 48 kHz. Parts are tested in the

circuit of Figure 1.

4. Refer to “Differential Input” discussion.

5. Backplane drive is in phase with segment drive for “OFF” segment, 180° out of phase for “ON” segment. Frequency is 20 times
conversion rate. Average DC component is less than 50mV.

TC7106

TC7106A

TC7107

TC7107A

3-1/2 DIGIT A/D CONVERTERS

3-186

TELCOM SEMICONDUCTOR, INC.

TC7106
TC7106A
TC7107
TC7107A

3-1/2 DIGIT A/D CONVERTERS

PIN CONFIGURATIONS

TC7106ACPL

TC7107AIPL

1
2
3
4

OSC

1

5
6
7
8

9
10
11
12

TEST
V

ANALOG
COMMON

C

AZ

V

+

D

NORMAL PIN

CONFIGURATION

13
14
15
16
17
18
19
20

40
39
38
37
36
35
34
33
32
31
30
29

28

27
26
25
24
23
22
21

2

C

2

B

2

A

2

F

2

E

2

D

3

B

3

F

3

E

3

AB

4

(MINUS SIGN)

10's

100's

1000's

(7106A/7107A)

100's

OSC

2

OSC

3

+
REF

V

–
REF

C

+

REF

C

–

REF

V

+
IN

V

–
IN

V

BUFF

V

INT

V

–

G
C
A
G
BP/GND

POL

3

3

3

2

TC7106AIJL
TC7107AIJL

1
2
3
4
5
6
7
8
9

10

11
12
13
14
15

16

17
18
19
20

100's

1000's

100's

REVERSE PIN

CONFIGURATION

40
39
38
37
36
35
34
33
32
31
30
29

28

27
26
25
24
23
22
21

D

1

C

1

B

1

A

1

F

1

G

1

E

1

1's

V

+

D

2

C

2

B

2

A

2

F

2

E

2

D

3

B

3

F

3

E

3

AB

4

(MINUS SIGN)

POL

D

1

C

1

B

1

A

1

F

1

G

1

E

1

1's

10's

OSC

TEST

V

ANALOG

COMMON

C

AZ

OSC

2

OSC

+
REF

V

–
REF

C

+

REF

C

–

REF

V

+
IN

V

–
IN

V

BUFF

V

INT

V

–

G
C
A
G

BP/GND

3

3

3

2

(7106A/7107A)

3

1

27
26
25
24
23

7
8

9
10
11

NC
G

2

NC
NC

TEST

OSC

3

NC

OSC

2

OSC

1

V

+

D

1

C

1

B

1

12 13 14 15 16 17 18 19 20 21 22

38 37 36 35 34

REF HI

A

1F1

TC7106ACKW
TC7107ACKW

(FLAT PACKAGE)

394041424344

28

29

30

31

32

33

6

5

4

3

2

1

REF LO

C

REFCREF

COM

IN HI

IN LO

A/Z

BUFF

INT

V

–

G

1E1D2C2B2A2F2E2D3

C

3

A

3

G

3

BP/GND
POL
AB

4

E

3

F

3

B

3

33
32
31
30
29

13
14
15
16
17

REF LO
C

REF

F

1

G

1

E

1

D

2

C

2

NC
B

2

A

2

F

2

E

2

D

3

18 19 20 21 22 23 24 25 26 27 28

44 43 42 41 40

A

1

B

3F3

TC7106ACLW
TC7107ACLW

(PLCC)

123456

34

35

36

37

38

39

12

11

10

9

8

7

B1C1D1V+NC

OSC1OSC2OSC3TEST

REF HI

E

3AB4

POL

NC

BP/GND

G

3A3C3G2

C

REF

COMMON
IN HI
NC
IN LO
A/Z
BUFF
INT
V

–

3-187

TELCOM SEMICONDUCTOR, INC.

7

6

5

4

3

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2

8

PIN DESCRIPTION

Pin No. Pin No.

40-Pin PDIP 40-Pin PDIP

(Normal) (Reverse) Symbol Description

1 (40) V

+

Positive supply voltage.

2 (39) D

1

Activates the D section of the units display.

3 (38) C

1

Activates the C section of the units display.

4 (37) B

1

Activates the B section of the units display.

5 (36) A

1

Activates the A section of the units display.

6 (35) F

1

Activates the F section of the units display.

7 (34) G

1

Activates the G section of the units display.

8 (33) E

1

Activates the E section of the units display.

9 (32) D

2

Activates the D section of the tens display.

10 (31) C

2

Activates the C section of the tens display.

11 (30) B

2

Activates the B section of the tens display.

12 (29) A

2

Activates the A section of the tens display.

13 (28) F

2

Activates the F section of the tens display.

14 (27) E

2

Activates the E section of the tens display.

15 (26) D

3

Activates the D section of the hundreds display.

16 (25) B

3

Activates the B section of the hundreds display.

17 (24) F

3

Activates the F section of the hundreds display.

18 (23) E

3

Activates the E section of the hundreds display.

19 (22) AB

4

Activates both halves of the 1 in the thousands display.
20 (21) POL Activates the negative polarity display.
21 (20) BP LCD Backplane drive output (TC7106A).

Digital ground (TC7107A).
22 (19) G

3

Activates the G section of the hundreds display.
23 (18) A

3

Activates the A section of the hundreds display.
24 (17) C

3

Activates the C section of the hundreds display.
25 (16) G

2

Activates the G section of the tens display.
26 (15) V

–

Negative power supply voltage.
27 (14) V

INT

Integrator output. Connection point for integration capacitor. See

INTEGRATING CAPACITOR section for more details
28 (13) V

BUFF

Integration resistor connection. Use a 47kΩ resistor for a 200mV full-

scale range and a 470kΩ resistor for 2V full-scale range.
29 (12) C

AZ

The size of the auto-zero capacitor influences system noise. Use a

0.47µF capacitor for 200mV full scale, and a 0.047µF capacitor for

2V full scale. See Paragraph on AUTO-ZERO CAPACITOR for more

details.
30 (11) V

–
IN

The analog LOW input is connected to this pin.
31 (10) V

+
IN

The analog HIGH input signal is connected to this pin.
32 (9) ANALOG This pin is primarily used to set the analog common-mode voltage

for battery operation or in systems where the input signal is

referenced to the power supply. It also acts as a reference voltage

source. See paragraph on ANALOG COMMON for more details.
33 (8) C

–
REF

See pin 34.

COMMON

GND

TC7106

TC7106A

TC7107

TC7107A

3-1/2 DIGIT A/D CONVERTERS

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TC7106
TC7106A
TC7107
TC7107A

3-1/2 DIGIT A/D CONVERTERS

GENERAL THEORY OF OPERATION
DUAL SLOPE CONVERSION PRINCIPLES

(All Pin Designations Refer to the 40-Pin DIP)

The TC7106A and TC7107A are dual slope, integrating
analog-to-digital converters. An understanding of the dual
slope conversion technique will aid in following the detailed
operation theory.

The conventional dual slope converter measurement
cycle has two distinct phases:

• Input Signal Integration

• Reference Voltage Integration (Deintegration)

The input signal being converted is integrated for a fixed
time period (TSI). Time is measured by counting clock
pulses. An opposite polarity constant reference voltage is
then integrated until the integrator output voltage returns to
zero. The reference integration time is directly proportional
to the input signal (TRI). (Figure 2A).

In a simple dual slope converter a complete conversion
requires the integrator output to “ramp-up” and “ramp­down.”

A simple mathematical equation relates the input signal,
reference voltage and integration time:

VIN(t)dt =

Figure 2A. Basic Dual Slope Converter

1

RC

∫

T

SI

VRT

RI

RC

0

where:
VR = Reference Voltage

TSI = Signal Integration Time (Fixed)
TRI = Reference Voltage Integration Time (Variable)

For a constant VIN:
VIN = V

R

T

RI

T

SI

+

–

REF

VOLTAGE

ANALOG

INPUT

SIGNAL

+

–

DISPLAY

SWITCH

DRIVER

CONTROL

LOGIC

INTEGRATOR

OUTPUT

CLOCK

COUNTER

POLARITY CONTROL

PHASE
CONTROL

V

IN

V

IN

V

FULL SCALE

1/2 V

FULL SCALE

VARIABLE
REFERENCE
INTEGRATE
TIME

FIXED

SIGNAL

INTEGRATE

TIME

INTEGRATOR

C

COMPARATOR

≈
≈

+/–

PIN DESCRIPTION (Cont.)

Pin No. Pin No.

40-Pin PDIP 40-Pin PDIP

(Normal) (Reverse) Symbol Description

34 (7) C

+
REF

A 0.1µF capacitor is used in most applications. If a large common­mode voltage exists (for example, the V

–

IN

pin is not at analog
common), and a 200mV scale is used, a 1µF capacitor is recom­mended and will hold the roll-over error to 0.5 count.

35 (6) V

–
REF

See pin 36.

36 (5) V

+
REF

The analog input required to generate a full-scale output (1999
counts). Place 100mV between pins 35 and 36 for 199.9mV
full-scale. Place 1V between pins 35 and 36 for 2V full scale. See
paragraph on REFERENCE VOLTAGE.

37 (4) Test Lamp test. When pulled HIGH (to V

+

) all segments will be turned on
and the display should read –1888. It may also be used as a negative
supply for externally-generated decimal points. See paragraph under
TEST for additional information.

38 (3) OSC

3

See pin 40.

39 (2) OSC

2

See pin 40.

40 (1) OSC

1

Pins 40, 39, 38 make up the oscillator section. For a 48kHz clock
(3 readings per section), connect pin 40 to the junction of a 100kΩ
resistor and a 100pF capacitor. The 100kΩ resistor is tied to pin 39
and the 100pF capacitor is tied to pin 38.