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DATEL, Inc., Mansfield, MA 02048 (USA)   

   Tel: (508)339-3000, (800)233-2765  Fax: (508)339-6356 

  •

   Email: sales@datel.com 

 •

  Internet: www.datel.com

Features

Figure 1. DMS-30PC Series Simplified Schematic

The DMS-30PC Series is a broad line of self-contained, fully operational, 3½

digit voltmeters with large, easy-to-read LED displays.  The 0.56"(14.2mm) high

LED's are available in a wide variety of colors including red, orange, amber, yellow,

green, aqua, blue-green, and super-blue.  A high-intensity version of the red display is

optional, as are low-power versions of the red, orange, and green displays.

The small size (2.17" x 0.92" x 0.56") of DMS-30PC meters is achieved by

integrating their display, display drivers, reference circuit, and A/D converter into in a

single, epoxy-encapsulated assembly. The device's 12-pin, component-like, DIP

package is both vibration and moisture proof.  Each package incorporates a built-in

color filter and bezel and is easily mounted in either panels or pc cards.

These meters are available in four differential input voltage ranges (±200mV,

±2V, ±20V and ±200V).  Input impedance is 1,000 megohms for the ±200mV and

±2V inputs and 1 megohm for the ±20V and ±200V inputs.  CMRR for all devices is

86dB, and inputs are overvoltage protected to ±250V.

Each meter incorporates an extremely stable, double-regulated reference and is

fully calibrated prior to potting.  We guarantee outstanding initial accuracy (±1 count)

and excellent stability (±0.15 counts/°C).  All models operate from a single +5V

supply, and the low-power models draw as little as 10mA (50mW total power).  A

DISPLAY TEST function is standard on each device.

For popular applications (4-to-20mA, rms-to-dc conversion, ac line power, J and

K thermocouples, etc.), the DMS-30PC Series includes a complete line of optional

"plug-on" application boards that conveniently convert your meter into an applica-

tion-specific instrument.

Large (0.56"/14.2mm) LED display

8 LED colors

Low-power LED’s optional

Epoxy-encapsulated, 12-pin DIP with

built-in color filter and bezel

Miniature size:

2.17"  x 0.92" x 0.56"

55mm x 23mm x 14mm

Panel or pc-board mountable

4 differential input voltage ranges

Auto-calibration, ±1 count accuracy

User-selectable decimal point placement

Single +5V supply (60mW for low-power

models)

0 to +60°C temperature range

Numerous "plug-on" application boards

Low cost

Actual Size

3½ Digit, LED Display

Low-Power, Miniature

Digital Panel Voltmeters

DMS-30PC Series

®

®

+1.23V REFERENCE OUT

(+) INPUT HI

(–) INPUT LO

ANALOG

COMMON

REFERENCE OUT

REFERENCE IN

+5V SUPPLY

R1

DP 1

DP 2

DP 3

6

5

4

9

11

12

10

8

7

1

3

DC/DC

CONVERTER

2

DISPLAY TEST

5V RETURN

+5V

–5V

+5V

1.23V

REF.

R2 

+2.0V

DATA

909k

R2 is not used on ±200mV (-0) models or ±2V (-1) models.

R2 = 100k on ±20V (-2) models and 9.1k on ±200V (-3) models.

V+

V–

A/D

CONVERTER

0 Vdc

0.01µF

1.82k

NEW!

 Super-Bright Blue

and Blue-Green LED Models

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2

Performance/Functional Specifications

Typical at T

A

 = +25°C and supply voltage = +5V using the single-ended input circuit,

unless otherwise noted.

DMS-30PC

3 ½   D I G I T ,   L E D   D I S P L A Y   D I G I T A L   P A N E L   V O L T M E T E R S

DMS-30PC - 1 - R S

LED Color:

AS = Standard Amber

BS = Super Blue

GS = Standard Green

OS = Standard Orange

QS = Standard Aqua

RS = Standard Red

YS = Standard Yellow

RH = High-Intensity Red

GL = Low-Power Green

OL = Low-Power Orange

RL = Low-Power Red

VFS = Blue-Green

Technical Notes

1. +1.23V REFERENCE OUTPUT (Pin 9):  This pin is the output of the

meter’s precision +1.23V internal reference, and it is referenced to

ANALOG COMMON (pin 10) which sits at a potential of approxi-

mately +2V.  This output should be buffered if used to drive external

loads since sourcing more than 15µA from pin 9 can affect both the

initial accuracy and temperature drift of the meter.

2. ANALOG COMMON (Pin 10):  This pin is connected to an internal,

low-noise, "relative" ground.  It is used in certain differential and

"floating" measurements as described in the Applications section of

this data sheet and Ap Note 3 of the DATEL Panel Meter Catalog.

Pin 10 should not be connected to pin 3 (5V RETURN) or to your

system’s analog ground.

3. REFERENCE OUTPUT (Pin 8) and INPUT (Pin 7): Pin 8 is a

precision reference actively trimmed at the factory.  In normal

operation, pin 8 must be tied to pin 7 to achieve all listed accuracy

and drift specifications.

Accessories:

DMS-30-CP

Panel cutout punch

DMS-BZL1

DMS-30 bezel assembly

DMS-BZL2

DMS-30 bezel assembly with sealing gasket

RN-DMS

Gain/offset potentiometer kit for DMS-EB,

DMS-EB-AC/DC and DMS-EB-DC/DC

Add-On Application Boards:

DMS-EB

Multi-purpose (gain/offset, 4-20mA, etc.)

DMS-EB-HTB

High-accuracy temperature probe sensing for

±200mV models

DMS-EB-DC/DC

Provides isolated +5V power

DMS-EB-TCJ

J-type thermocouple inputs for ±2V models

DMS-EB-TCK

K-type thermocouple inputs for ±2V models

DMS-EB-RMS

For true rms measurements of ac voltages

DMS-EB-AC/DC

For ac line-powered applications

DMS-EB-LP

For 4-to-20mA loop-powered applications

Input Range:

0 = ±200mV

1 = ±2V

2 = ±20V

3 = ±200V Available on the

following models only:

-BS (Super Blue)

-GS (Standard Green)

-RS (Standard Red)

-RL (Low-Power Red)

-VFS (Blue-Green)

Ordering Information

Œ

Applies for transient or continuous overvoltages applied to (+) INPUT HI (pin 11)

with (–) INPUT LO (pin 12) properly connected. Pin 12 is not overvoltage protected

(see Figure 1). Voltages applied to pin 12 should not exceed the supply voltage.



See Technical Notes.

A panel-mount retaining clip is supplied with each model.

Analog Inputs

Min.

Typ.

Max.

Units

Full Scale Input Range:

DMS-30PC-0

--

±200

--

mV

DMS-30PC-1

--

±2

--

Volts

DMS-30PC-2

--

±20

--

Volts

DMS-30PC-3

--

±200

--

Volts

Input Impedance:

DMS-30PC-0, -1

100

1000

--

M

DMS-30PC-2, -3

0.8

1

--

M

Overvoltage Protection  Œ

--

--

±250

Volts

Common Mode Voltage Range

--

--

±2

Volts

CMRR (dc to 60Hz)

--

86

--

dB

Control Inputs

  

Decimal Point Placement (Pins 4-6)

Tie to pin 3 to activate

Display Test  (Pin 2)

Tie to +5V to activate all segments

Performance

Sampling Rate

2.5 samples per second

Accuracy (3 minute warm-up):

DMS-30PC-0 (V

IN

 = +0.19V)

--

±1

±2

Counts

DMS-30PC-1 (V

IN

 = +1.9V)

--

±1

±2

Counts

DMS-30PC-2 (V

IN

 = +19V)

--

±2

±3

Counts

DMS-30PC-3 (V

IN

 = +190V)

--

±2

±3

Counts

Zero Reading (V

IN

 = 0 Volts)

"– 001"

"000"

"001"

Temperature Drift (0 to +60°C)

--

±0.15

±0.3

Cnts/°C

+1.23V Reference Output (Pin 9)  

+1.20

+1.23

+1.25

Volts

Power Supply Requirements

Supply Voltage

+4.75

+5.00

+5.25

Volts

Supply Current:

Standard Models

--

+150

+225

mA

Low-Power Models:

Red display

--

+12

+17

mA

Green or orange display

--

+60

+100

mA

Display

Display Type and Size

3½ Digit LED, 0.56"/14.2mm high

Polarity Indication

Autopolarity ("–" for negative V

IN

)

Overrange Indication

"–1_ _ _ " for negative V

IN

"1_ _ _ " for positive V

IN

Physical/Environmental

Operating Temperature

0

--

+60

°C

Storage Temperature

– 40

--

+75

°C

Humidity (Non-condensing)

0

--

95

%

Case Material

Polycarbonate

Weight

0.75 ounces (21 grams)

Order on-line at www.datel.com

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3 ½   D I G I T ,   L E D   D I S P L A Y   D I G I T A L   P A N E L   V O L T M E T E R S

DMS-30PC

Applications

1. Single-Ended Input Configurations:  True single-ended

measurements can be made with any DMS-30PC meter.  The

circuit of Figure 2 avoids problems normally associated with

ground-loop currents.  Separate ground runs should be used for

5V RETURN (pin 3) and (–) INPUT LO (pin 12). This will ensure

that large LED currents will not flow in the wiring that connects

V

IN

 to (–) INPUT LO (pin 12). Ground-loop currents can cause

unstable readings.

Figure 2. Single-Ended Input Configuration

DMS-30PC meters are highly versatile devices that can be used in

hundreds of applications. The application circuits chosen for this

section have historically received many inquiries. Every attempt has

been made to ensure technical accuracy, and all of the following

circuits have been prototyped and tested to ensure functionality.

Please keep in mind, however, that real-world applications are

seldom as straightforward as the approaches presented here. Most

applications have many more components — and many more

connections — than the illustrations show.

The simplified schematic shown in Figure 1 can be very useful when

debugging a malfunctioning panel meter circuit, particularly if the

user has some knowledge of operational amplifiers (op amps). The

meter's high-impedance input consists of an op amp powered from a

±5Vdc power supply (the –5V is internally generated). Knowing this,

one can easily see why input signals applied to (–) INPUT LO and

(+) INPUT HI have to be kept within the power supply rails of ±5V.

Also note that only pin 11 has a current-limiting 909k

 series

resistor. High input voltages that have a common ground with pin 3

(5V RETURN) should only be applied to pin 11 ((+) INPUT HI) and

never to pin 12. In these high-voltage cases, pin 12 should always

be tied to pin 3 (5V RETURN).

One of the simplified schematic's noteworthy features is that it

shows internal voltage values.  It also shows that pin 3 is the meter's

zero-volt reference point — regardless of the type of power or signal

source used. This is an important point to keep in mind when a

digital or analog multimeter is used to make system measurements.

The multimeter's negative lead (usually the black one) must be

connected to pin 3 (5V RETURN).

4. DISPLAY TEST (Pin 2):  Connecting pin 2 to +5V SUPPLY (pin

1) will activate all LED segments, except the decimal points, and

the display will read "1888" regardless of the actual applied input.

If a negative input is applied, DISPLAY TEST will also activate

the minus sign.  

To protect the LED's, the display should not

be left in the "test" mode for more than 10 seconds.

5. Decimal Point Placement: The location of the decimal point is

user-selectable, and the decimal point control pins (DP1-DP3)

are active low functions.  Select the desired decimal point by

tying the appropriate pin (pin 4, 5 or 6) to pin 3 (5V RETURN).

Unused decimal point location pins should be left open.

Hard wiring is preferable, however, you can use logic gates to

exercise dynamic control over the location of the decimal point if

the following drive conditions are met:

Model

Applied "0" Voltage Load Current*

DMS-30PC-X-RL

+0.05V max.

0.7mA max.

All Others

+0.4V max.

6mA max.

* The driving gates must be able to sink this much current

(I

OL

) with a logic "0" output.

6. Gain Adjust:  There is a gain-adjust potentiometer on the back

of each meter.  It has approximately ±50 counts (±2.5%) of

adjustment range.  Since these devices essentially have no zero/

offset errors, a gain adjustment is effectively an overall accuracy

adjustment.  Though they may be performed at any point (except

zero), accuracy adjustments are most effective when performed

with higher level input signals.  The circuit shown in Figure 10

provides ±10% range of adjustment.

7. Soldering Methods:  All models in the DMS-30PC Series easily

withstand most common wave soldering operations.  We

recommend, however, that you evaluate the effects your

particular soldering techniques may have on the meter's plastic

case and high-precision electrical performance.  We recommend

the use of water-soluble solders and thorough cleaning

procedures.

8. Suggested Mating Connectors:

Panel mounted:

Connector housing

DATEL P/N 39-2079400

Terminal type

DATEL P/N 39-2099090

Crimping tool

DATEL P/N 39-2099000

Wire size

22 to 26 AWG

Insulation diameter

0.062" (1.57mm) maximum

Stripping length

0.100 to 0.125" (2.54 to 3.17mm)

Board mounted:

Socket

DATEL P/N 39-2359625

1

12

3

+5V SUP

(–) IN LO

5V RET

DATEL

UPA-5/500

120 VAC

11

(+) IN HI

6

DP1

+

AC to DC Converter

V

IN

DMS-30PC-1

8

7

REF OUT

REF IN

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4

DMS-30PC

3 ½   D I G I T ,   L E D   D I S P L A Y   D I G I T A L   P A N E L   V O L T M E T E R S

Figure 3. Differential Input Configuration

R2

R1 + R2

x V

IN 

 = Reading

50k

 < R1 + R2 < 10M

Figure 6. Floating Input Measurements

(Alternate Configuration)

Figure 5. Floating Input Measurements

Figure 4. Input Attenuation Circuit

Connecting pin 10 (ANALOG COMMON) or pin 3 (5V RETURN)

to (–) INPUT LO (pin 12) provides the reference point for the

meter's input.

A "floating" input is a signal that has no galvanic connection to

the meter's power supply. In the figures below, the 1.5V battery

illustrates a true floating input.

R

Shunt

= R1 = V

Fsr

/ I

Fsr

Where:

V

Fsr

= Full scale reading (in Volts)

I

Fsr

= Relative full scale current (in Amps)

5. Process Control (4-to-20mA) Measurements:  In many

common process-control applications, a 4-to-20mA current loop

is used to transmit information.  Because DMS-30PC meters have

such high input impedance, a simple shunt resistor across the

meter's input can be used to convert the loop current to a voltage.

See Figure 7.  The value of the shunt resistor is a function of the

scaling requirements of the particular application and can be

calculated using the following equation:

Applications

2. Differential Input Configurations:  Differential measurements

can be made with all DMS-30PC meters.  Figure 3, though not a

practical real-world application, uses a voltage divider to

demonstrate the concept of a differential input signal. Be careful

not to exceed the ±2V common mode voltage limitation for 5V-

powered meters.

3. Engineering Scaling:  For measuring voltages greater than the

full scale input range of a given meter, the input signal must be

attenuated.  A simple voltage divider (similar to that shown in

Figure 4) will scale the input to within the range of the selected

meter.  R1 and R2 should be precision, ±1%, metal-film resistors

with absolute TCR's less than 50ppm/°C. See Ap Note 4 for more

information on engineering scaling.

4. Floating Signal Source Measurements:  Floating signals can

be measured using the circuits shown in Figures 5 and 6.

1

12

3

+5V SUP

(–) IN LO

5V RET

DATEL

UPA-5/500

120 VAC

11

(+) IN HI

6

AC to DC Converter

R2

R1

R3

1k

1k

1k

8

7

REF IN

DP1

REF OUT

DMS-30PC-1

R2

11

12

(+) IN HI

(–) IN LO

V

IN

R1

+

1

3

+5V SUP

5V RET

DATEL

UPA-5/500

120 VAC

AC to DC Converter

8

7

REF OUT

REF IN

DMS-30PC-1

1

3

+5V SUP

5V RET

DATEL

UPA-5/500

120 VAC

6

DP1

AC to DC Converter

DMS-30PC-1

12

(–) IN LO

11

(+) IN HI

1.5V

CELL

+

8

REF OUT

REF IN

12

7

1

3

5V RET

6

DP1

12

(–) IN LO

10

ANA COMM

11

(+) IN HI

1.5V

CELL

+

8

7

REF OUT

REF IN

DMS-30PC-1

+5V SUP

DATEL

UPA-5/500

120 VAC

AC to DC Converter

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3 ½   D I G I T ,   L E D   D I S P L A Y   D I G I T A L   P A N E L   V O L T M E T E R S

DMS-30PC

Figure 10. External Gain Adjustment

Figure 8. 4.5-18V Power Supply Monitor

Figure 9. Basic DC Ammeter Circuit

Figure 7. 4-to-20mA Current Loop Operation

To calibrate the circuit of Figure 7, perform the following:

1. With 4mA applied, adjust the 50k

 potentiometer (R2) to

display a reading of "000" (assuming that is the desired

reading).

2. With 20mA applied, adjust the gain-adjust potentiometer on

the back of the meter to display a reading of "1000".  For

different full scale readings, alter the value of R

Shunt

 accordingly.

Example: For a meter with a 2V full scale input (1.999 full

scale reading) and a desired display reading of

"1000" (with an input of 20mA),  V

Fsr

 

= 1.000 Volts

R

Shunt

= 1.000V/(0.020 – 0.004)A

R

Shunt

= 1.000V/0.016A = 62.5 Ohms

6Power Supply Monitoring:  One of the most common digital

panel meter applications involves monitoring the output voltage of

the system power supply — often this supply also powers the

meter itself. The low-power, red LED DMS-30PC-2-RL can be

configured to allow power supply monitoring over the range of

4.5-18Vdc. The circuit in Figure 8 uses a low-drop-out, three-

terminal regulator (LM-2931Z-5, available from National

Semiconductor) to provide regulated 5V power to the meter. The

LM-2931 was chosen because it has the following on-chip

protection features: reverse polarity, short circuit and thermal run-

away. When using other, higher-power, DMS-30PC models with

three-terminal regulators, be sure to consult the regulator

manufacturer's data sheet to ensure the regulator is being

utilized safely and correctly.

7. Digital Ammeter:  Digital ammeters are finding ever-increasing

usage because analog-style ammeters (moving-vane types) now

cost roughly the same as their digital counterparts. Additionally,

analog ammeters are not nearly as rugged as modern digital

panel voltmeters. Figure 9 illustrates a typical ammeter

application. The circuit uses a ±200mV input meter

— the preferred range for most ammeters — to measure the

voltage developed across a 0.1

 current shunt. The circuit

shown represents a basic ammeter connection diagram. A

detailed application note describing digital dc ammeters is

included in DATEL's new Digital Panel Meter Databook.

8. External Gain Adjustment:  Connect REFERENCE OUT

(pin 8) to REFERENCE IN (pin 7) for normal, factory calibrated,

operation.  Use the +1.23V REFERENCE OUT (pin 9) for

applications needing external gain adjustment.  Figure 10 shows

the wiring configuration for each model.  Calibration is performed

with a precise, near-full-scale, input voltage.

Applications

1

3

5V RET

DATEL

UPA-5/500

120 VAC

AC to DC Converter

DMS-30PC-1

12

(–) IN LO

10

ANA COMM

11

(+) IN HI

R1

+

4-20mA

50k

R2

8

7

REF OUT

REF IN

9

1.23V

REF

5V SUP

DMS-30PC-2-RL

5

7

12

+

11

1

4.5 - 18Vdc

LM2931Z-5

GND

IN

OUT

+5V SUP

3

5V RET

DP2

REF

IN

(+) IN HI

8

REF

OUT

(–) IN LO

22µF

10V

+

9

(+) IN HI

(–) IN LO

ANA COMM

10

1.23V REF

1k

10 to 20 Turns

8

REF IN

11

1k

10 to 20 Turns

8.45k, 1%

8.45k, 1%

5V RET

Connections

for ±2V, ±20V 

and ±200V models

Connections

for ±200mV

models

7

NC

12

3

DMS-30PC

12

VOLTAGE

CALIBRATOR

OUT

COM

DMS-30PC-0

6

3

+

1

1.5 Amp (Load Current)

5Vdc

7

8

+5V SUP

5V RET

DP1

REF OUT

REF IN

11

0.150V

(+) IN HI

0.1

R

Shunt

Load

(3.3   )

12

(–) IN LO

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DATEL, Inc.  11 Cabot Boulevard, Mansfield, MA 02048-1151

Tel: (508) 339-3000

 (800) 233-2765     Fax: (508) 339-6356

Internet: www.datel.com      Email: sales@datel.com

DATEL (UK) LTD. Tadley, England  Tel: (01256)-880444

DATEL S.A.R.L. Montigny Le Bretonneux, France  Tel: 01-34-60-01-01

DATEL GmbH München, Germany  Tel: 89-544334-0

DATEL KK Tokyo, Japan  Tel: 3-3779-1031, Osaka  Tel: 6-6354-2025

DATEL makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein

do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. The DATEL logo is a registered DATEL, Inc. trademark.

®

®

DMS-30PC

3 ½   D I G I T ,   L E D   D I S P L A Y   D I G I T A L   P A N E L   V O L T M E T E R S

MECHANICAL DIMENSIONS: Inches (mm)

TOLERANCES: 2 PL DEC ±0.02 (±0.51)

3 PL DEC ±0.010 (±0.254)

LEAD DIMENSIONS: 0.025 (0.635) x 0.025 (0.635) NOMINAL

RECOMMENDED PC BOARD FINISHED HOLE DIAMETER:

0.042 ±0.003 (1.067 ±0.076)

Mechanical Specifications

DS-0258F

03/01

MADE IN USA

®

®

BEZEL INSTALLATION

PANEL

BEZEL

RETAINING CLIP INSTALLATION

PANEL

#2-56 INSERT

0.156 (3.96) DEEP

FRONT VIEW

1.270

(32.26)

0.187

(4.75)

OPTIONAL BEZEL (DMS-BZL1 and DMS-BZL2)

2.35 (59.69)

2.118 (53.80)

0.093 (2.362) DIAMETER (4 REQUIRED)

ONLY WHEN USING OPTIONAL BEZEL ASSEMBLY

RECOMMENDED DRILL AND PANEL CUTOUT DIMENSIONS

INTERNAL CORNER RADII:

0.032 (0.81) MAX.

1.07

(27.18)

0.878

(22.30)

0.096

(2.44)

0.116

(2.95)

2.55 (64.77)

PANEL CUTOUT

MADE IN USA

DMS-30PC-X-XX

PIN #1

IDENTIFIER

FRONT VIEW

+5V SUPPLY

DISPLAY TEST

5V RETURN

DP3

DP2

DP1

1

2

3

4

5

6

12

11

10

9

8

7

(–) INPUT LO

(+) INPUT HI

ANALOG COMMON

+1.23V REFERENCE OUT

REFERENCE OUT

REFERENCE IN

DP1

DP2

DP3

2.17

(55.1)

2.09

(53.1)

1.80

(45.7)

0.25 (6.4) TYP.

0.15

(3.7)

TYP.

0.040

(1.02)

0.040

(1.02)

0.10

(2.5)

TYP.

0.50

(12.7)

0.17

(4.3)

TYP.

0.92

(23.4)

0.84

(21.3)

0.560

(14.22)

®

®

0.040

(1.02)

0.250

(6.35)

0.260

(6.60)

PIN 1

CALIBRATION POTENTIOMETER HOLE LOCATION

0.125 (3.175) DIAMETER

(USE ONLY WHEN PC BOARD MOUNTING)

ISO 9001

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