MICROCHIP TC14433 Technical data
TC14433/A
3-1/2 Digit, Analog-to-Digital Converter
Features
• Accuracy: ±0.05% of Reading ±1 Count
• Two Voltage Ranges: 1.999V and 199.9 mV
• Up to 25 Conversions Per Second
> 1000M Ohms
•Z
IN
• Single Positive Voltage Reference
• Auto-Polarity and Auto-Zero
• Overrange and Underrange Signals Available
• Operates in Auto-Ranging Circuits
• Uses On-Chip System Clock or External Clock
• Wide Supply Range: ±4.5V to ±8V
Applications
• PortableInstruments
• Digital Voltmeters
• Digital Panel Meters
• Digital Scales
• Digital Thermometers
• Remote A/D Sensing Systems
• MPU Systems
Device Selection Table
Package Type
24-Pin CERDIP (Wide)
V
AG
V
REF
V
X
R
1
R1/C
1
C
1
CO
1
CO
2
DU
CLK1
CLK0
V
EE
24-Pin PDIP (Wide)
24-Pin SOIC (Wide)
1
2
3
4
5
TC14433/A
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
28-Pin PLCC
V
DD
Q
3
Q
2
Q
1
Q
0
DS
DS
DS
DS
OR
EOC
V
SS
1
2
3
4
Part Num ber Package
TC14433AEJG 24-Pin CERDIP
Temperature
Range
-40°C to +85°C
(Wide)
TC14433AELI 28-Pin PLCC -40°C to +85°C
TC14433AEPG 24-Pin PDIP
-40°C to +85°C
(Wide)
TC14433COG 24-Pin SOIC
0°C to +70°C
(Wide)
TC14433EJG 24-Pin CERDIP
-40°C to +85°C
(Wide)
TC14433ELI 28-Pin PLCC -40°C to +85°C
TC14433EPG 24-Pin PDIP
-40°C to +85°C
(Wide)
3
EOC
2
Q
OR
25
24
23
22
21
20
19
Q
Q
DS
DS
DS
DS
1
0
1
2
3
4
REF
X
V
4 3 2 1 27 2628
R
5
1
R1/C
6
1
C
7
1
8
NC NC
CO
9
1
CO
10
2
11
DU
12 13 14 15 17 18
CLK1
Note 1: NC = No internal connection (In 28-Pin PLCC).
2: 24-Pin SOIC (Wide) package, only for
TC14433 device.
AG
V
NC
V
TC14433/A
16
EE
NC
V
CLK0
VDDQ
SS
V
2002 Microchip TechnologyInc. DS21394B-page 1
TC14433/A
General Description
The TC14433 is a low power, high performance,
monolithic CMOS 3-1/2 di git A/D converter. The
TC14433 combines both analog and digital circuits on
a single IC, thus minimizing the number of external
components.
This dual slope A/D converter provides automatic
polarity and zero correction with the addition of two
external resistors and two capacitors. The full scale
voltage range of this ratiometric IC extends from 199.9
millivolts to 1.999volts.TheTC14433can operateover
a wide range of power supply voltages, including
batteries and standard 5-volt supplies.
Typical Application
MCP1525
+5V
1µF
V
X
0.1µF**
0.1µF**
*R
= 470kΩ for 2V Range
1
R
= 27kΩ for 200mV Range
1
**Mylar Capacitor
300k
R
*
R
1
20k
1µF
C
11 10 2 12 24
3
1
4
TC14433
5
6
7
8
19 18 17 16
15
DS
DS
1
DS
2
23
22
21
20
13
9
14
14013B
DS
3
+5V
0.1
-5V
5
3
4
9
11
-5V
4
The TC14433A features improved performance over
the industry standard TC14433. Rollover, which is the
measurement of identical positive and negative
signals, i s specified to have the same reading within
one count f or the TC14433A. Power consumption of
the TC14433A is typically 4mW, approximately onehalf that of the industry standard TC14433.
The TC14433/A is available in 24-Pin PDIP, 24- Pin
CERDIP, 24-Pin SOI C (TC14433 device only), and
28-Pin PLCC packages.
-5V
+5V
0.1µF
1
16
4
2
3
5
4543B
8
67
-5V
-5V
6
1
S
Q
D
2
Q
C
R
8
S
13
Q
D
12
Q
C
R
714
10
+5V
10
11
12
13
14
15
9
+5V
+5V
7
6
5
4
3
2
1
1413
-5V
-5V
MPS-A12
-5V
51k
50µF
-5V
10
11
12
13
14
15
16
Minus Sign
Common
Anode Led
Display
0.1µF
MPS-A12
Segment
Resistors
150Ω (7)
200Ω
(4)
fgedcba
DS21394B-page 2
2002 Microchip TechnologyInc.
TC14433/A
1.0 ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings*
Supply Voltage (VDD–VEE)................... -0.5V to +18V
*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.
Voltage on Any Pin:
ReferencetoV
.....................-0.5V to (VDD+0.5)
EE
DC Current, Any Pin: ........................................ ±10mA
Power Dissipation (T
≤ 70°C):
A
Plastic PLCC .................................................1.0W
Plastic PDIP.................................................. 940W
SOIC.............................................................940W
CERDIP .......................................................1.45W
Operating Temperature Range ...............0°C to +70°C
StorageTemperature Range..............-65°Cto +160°C
TC14433/A ELECTRIC AL SPECIFICATIONS
Electrical Characteristics: VDD=+5V,VEE=-5V,C1=0.1µF,(Mylar), C0=0.1µF, RC=300kΩ,R1=470kΩ @V
R
=27kΩ @V
1
Symbol Parameter Min Typ Max Min Typ Max Units Test Conditions
Analog Input T
SYE Rollover Error (Positive) and
Negative Full Scale
Symmetry
NL LinearityOutput Reading
(Note 1)
SOR Stability Output Reading
(Note 2)
ZOR Zero Output Reading — 0 0 ———LSD V
I
IN
CMRR Common mode Rejection — 65 — — —— dB V
Note 1: Accuracy - The accuracyof the meter at full scale is the accuracy of the setting of the referencevoltage. Zero is
Bias Current: Analog Input
recalculated during each conversion cycle. The meaningful specification is linearity. In other words, the deviation from
correct reading for all inputsother than positive full scaleand zero is definedas the linearity specification.
2: The LSD stability for 200mV scale is defined as the range that the LSD will occupy 95% of the time.
3: Pinnumbersreferto24-pinPDIP.
= 200mV, unless otherwise specified.
REF
-1 — +1 — — — Counts 200mV Full Scale
-0.05 +0.05 +0.05 — — — %rdg V
-1 count — +1 count — — — %rdg V
—— 2———LSDV
—— 3———LSDV
—
Reference Input
AnalogGround
—
—
= +25°C
A
±20
±20
±20
±100 —
±100 —
±100 —
=+25°C
T
A
—
—— pA
—— pA
V
V
V
—
pA
F
REF
IN-VIN
=2V
REF
=200mV
REF
=1.99V,
X
=2V
REF
=199mV,
X
=200mV
REF
=0V,V
X
=1.4V,V
X
=32kHz
OC
=2V,
=+V
REF
IN
=2V
REF
=2V,
2002 Microchip TechnologyInc. DS21394B-page 3
TC14433/A
TC14433/A ELECTRICA L SPECIFICATIONS (CONTINUED)
Electrical Characteristics: VDD=+5V,VEE=-5V,C1=0.1µF,(Mylar), C0=0.1µF, RC=300kΩ,R1=470kΩ @V
R
=27kΩ @V
1
= 200mV, unless otherwise specified.
REF
Symbol Parameter Min Typ Max Min Typ Max Units Test Conditions
Digital
V
OL
Output Voltage
— 0 0.05 — — 0.05 V VSS= 0 V, "0" Level
(Pins14to23)(Note 3)
— -5 -4.95 — — -4.95 V V
V
OH
Output Voltage
4.95 5 — 4.95 — — V VSS= 0V, "1" Level
(Pins14to23)(Note 3)
4.95 5 — 4.95 — — V V
I
OH
Output Current
(Pins14to23)
-0.2 -0.36 — -0.14 — — mA VSS=0V,VOH=4.6V
Source
- 0.5 -0.9 — -0.35 — — mA V
Source
I
OL
Output Current
(Pins14to23)
0.51 0.88 — 0.36 — — mA VSS=0V,VOL=0.4V
Sink
1.3 2.25 — 0.9 — — mA V
V
f
CLK
I
DU
Clock Frequency — 66 — — — — kHzRC=300kΩ
Input Current -DU — ±0.00001 ±0.3 — — ±1 µA
Power
I
Q
Quiescent Current: 14433A: — — — — — — — VDDto VEE,ISS=0
— 0.4 2 — — 3.7 mA V
— 1.4 4 — — 7.4 mA V
Quiescent Current: 14433: — — — — — — — V
— 0.9 2 — — 3.7 mA V
— 1.8 4 — — 7.4 mA V
PSRR Supply Rejection — 0.5 — — — — mV/V V
V
V
Note 1: Accuracy - The accuracyof the meter at full scale is the accuracy of the setting of the referencevoltage. Zero is
recalculated during each conversion cycle. The meaningful specification is linearity. In other words, the deviation from
correct reading for all inputsother than positive full scaleand zero is definedas the linearity specification.
2: The LSD stability for 200mV scale is defined as the range that the LSD will occupy 95% of the time.
3: Pinnumbersreferto24-pinPDIP.
=2V,
REF
= -5V, "0" Level
SS
= -5V, "1" Level
SS
=-5V,VOH=5V
SS
=-5V,
SS
= -4.5V Sink
OL
=5,VEE=-5
DD
=8,VEE=-8
DD
to VEE,ISS=0
DD
=5,VEE=-5
DD
=8,VEE=-8
DD
to VEE,ISS=0,
DD
=2V,
REF
=5,VEE=-5
DD
DS21394B-page 4
2002 Microchip TechnologyInc.
2.0 PIN DESCRIPTIONS
ThedescriptionsofthepinsarelistedinTable2.0.
TABLE 2-1: PIN FUNCTION TABLE
Pin No.
(24-Pin PDIP)
(24-Pin CERDIP)
(24-Pin SOIC)
12V
23V
34V
45R
56R
67C
79CO
810CO
9 11 DU Display update input pin. When DU is connected to the EOC output, every
10 12 CLK
11 13 CLK
12 14 V
13 16 V
14 17 EOC End of conversion output generates a pulse at the end of each conversion cycle.
15 18 OR
16 19 DS
17 20 DS
18 21 DS
19 23 DS
20 24 Q
Pin No.
(28-Pin PLCC)
Symbol Description
This is the analog ground. It has a high input impedance. The pin determines the
AG
reference level for the unknown input voltage (V
Reference voltage- Full scale outputisequalto the voltageapplied to V
REF
Therefore, full scale voltage of 1.999V requires 2V reference and 199.9mV full scale
requires a 200mV reference.V
to V
, the system is reset to the beginningof the conversioncycle.
EE
The unknowninput voltage (VX) is measured as a ratio of the reference voltage
X
(V
) in a rationetric A/D conversion.
REF
This pin is for external components used for the integration functionin the dual
1
slope conversion. Typical values are 0.1µF (mylar) capacitor for C
1/C1R1
1
=470kΩ (resistor)for2V fullscale.
R1=27kΩ (resistor)for 200mV full scale.Clock frequencyof66kHzgives 250msec
conversion time.
These pins are used for connecting the offset correction capacitor.
1
The recommended value is 0.1µF.
These pins are used for connecting the offset correction capacitor.
2
The recommended value is 0.1µF.
conversion is displayed. New data will be strobed into the output latches during the
conversion cycleif a positiveedgeis received on DU, prior to the ramp down cycle.
When this pin is driven from an external source, the voltageshould be referenced
to V
.
SS
Clock input pins. The TC14433 has its own oscillator system clock. Connecting a
1
single resistor between CLK
A crystalor OC circuit may be inserted in lieu of a resistor for improved CLK1,the
0
clock input, can be driven from an external clock source, which need only have
standardCMOSoutput drive.This pin is referenced to V
A300kΩ resistor yieldsa clock frequency of about66kHz.See Section5.0Typical
Characteristics. (Also see Figure 4-3 for alternatecircuits.)
Negative power current. Connection pin for the most negativesupply. Please note
EE
the current for the output drive circuit is returned through V
current is 0.8mA.
Negative powersupplyfor output circuitry. This pin sets the lowvoltage levelforthe
SS
outputpins (BCD,DigitSelects,EOC,OR). When connectedto analogground, the
output voltage is from analog ground to V
is from V
V
-3 volts and VEE.
DD
This generated pulse width is equal to one half the period of the system clock.
Overrange pin. Normally this pin is set high. When VXexceedsV
Digit select pin. The digit select output goes high when the respective digit is
4
selected. The MSD (1/2 digitturnson immediately afteran EOC pulse).
The remaining digits turn on in sequence from MSD to LSD.
3
To ensure that the BCD data has settled, an inter digitblanking time of two clock
2
periods is included.
Clock frequency divided by 80 equals multiplex rate. For example, a system clock of
1
60kHz gives a multiplex rate of 0.8kHz.
See Figure 4-4 for digit select timingdiagram.
0
TC14433/A
) and the reference voltage (V
X
functions as system reset also. When switched
REF
.
1
and CLK0sets the clock frequency.
1
forexternalclockinputs.
EE
. Typical supply
SS
. If connected to VEE, the output swing
to VDD. The recommended operating range for VSSis between the
EE
DD
the OR is low.
REF
REF
).
REF
.
2002 Microchip TechnologyInc. DS21394B-page 5
TC14433/A
TABLE 2-1: PIN FUNCTION TABLE (CONTINUED)
Pin No.
(24-Pin PDIP)
(24-Pin CERDIP)
(24-Pin SOIC)
21 25 Q
22 26 Q
23 27 Q
24 28 V
— 8 NC Not Used.
—15NCNotUsed.
—22NCNotUsed.
Pin No.
(28-Pin PLCC)
1NCNotUsed.
Symbol Description
BCD data outputpin. MultiplexedBCDoutputs contain threefulldigits of
1
informationduring digit selectDS
During DS1, the 1/2 digit, overrange,underrangeand polarity information
2
is available.
Refer to the Truth Table 4-1.
3
Positive power supply. This is the most positive power supply pin.
DD
,DS3,DS4.
2
DS21394B-page 6
2002 Microchip TechnologyInc.
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