+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
49
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
»
(1)
(1)
Figure 1. DMS-30PC Series simplifi ed schematic
DMS-30PC Series
3½ Digit, LED Display Low-Power,
Miniature Digital Panel Voltmeters
MPM_DMS_30PC.G01 Page 1 of 6
www.murata-ps.com
www.murata-ps.com/support
For full details go to
www.murata-ps.com/rohs
The DMS-30PC Series is a broad line of self-contained, fully operational, 3½ digit volt-
meters 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 fi lter 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 over-
voltage 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 ther-
mocouples, etc.), the DMS-30PC Series includes a complete line of optional "plug-on" appli-
cation boards that conveniently convert your meter into an application-specifi c instrument.
FEATURES
Large (0.56"/14.2mm) LED display
8 LED colors
Low-power LED’s optional
Epoxy-encapsulated, 12-pin DIP with built-in color fi lter
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
SIMPLIFIED SCHEMATIC DIAGRAM
Performance/Functional Specifi cations
Typical at TA = +25°C and supply voltage = +5V using the single-ended input
circuit, unless otherwise noted.
DMS-30PC - 1 - R S - C
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
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 exter-
nal 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
"fl oating" measurements as described in the Applications section
of this data sheet and Ap Note DMS-AN3 at
http://www.murata-ps.com/data/meters/dms-an3.pdf. 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 preci-
sion reference actively trimmed at the factory. In normal operation,
pin 8 must be tied to pin 7 to achieve all listed accuracy and drift
specifi cations.
Accessories:
DMS-30-CP Panel cutout punch
DMS-BZL1-C DMS-30 bezel assembly
DMS-BZL2-C DMS-30 bezel assembly with sealing gasket
Add-On Application Boards:
DMS-EB-C 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-RMS-C For true rms measurements of ac voltages
DMS-EB-AC/DC-C For ac line-powered applications
Input Range:
0 = ±200mV
1 = ±2V
2 = ±20V
3 = ±200V
±200V available on the
following models only:
-BS (Super Blue)
-GS (Standard Green)
-RS (Standard Red)
-RL (Low-Power Red)
-VFS (Blue-Green)
➀ 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.
➁ 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 Impedence: –
DMS-30PC-0, -1 100 1000 – MΩ
DMS-30PC-2, -3 0.8 1 – MΩ
Overvoltage Protection ➀– – ±250 Volts
Common Mode Voltage Range – – ±2 Volts
CMRR (dc to 60Hz) –86–dB
Control Inputs ➁
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 reading per second
Accuracy (3 minute warm-up):
DMS-30PC-0 (Vin = +0.19V) – ±1 ±3 Counts
DMS-30PC-1 (Vin = +1.9V) – ±1 ±3 Counts
DMS-30PC-2 (Vin = +19V) – ±2 ±3 Counts
DMS-30PC-3 (Vin = +190V) – ±2 ±3 Counts
Zero Reading (Vin = 0 Volts) “–001” “000” “001”
Temperature Drift (0 = +60°C) – ±0.2 ±0.4 Cnts/°C
+1.23V Reference Output (Pin 9) ➁+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, 0.56"/14.2mm high LED
Polarity Indication Autopolarity ("–" for negative Vin)
Overrange Indication "–1_ _ _" for negative inputs
"1_ _ _" for positive inputs
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)
Ordering Information
Add -C for RoHS
See www.murata-ps.com/dpm-availability for model-specifi c availability.
DMS-30PC Series
3½ Digit, LED Display Low-Power,
Miniature Digital Panel Voltmeters
MPM_DMS_30PC.G01 Page 2 of 6
www.murata-ps.com/support
TECHNICAL NOTES
1. Single-Ended Input Confi gurations: True single-ended measure-
ments 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
fl ow in the wiring that connects VIN to (–) INPUT LO (pin 12). Ground-
loop currents can cause unstable readings.
Figure 2. Single-Ended Input Confi guration
DMS-30PC meters are highly versatile devices that can be used in
hundreds of applications. The application circuits chosen for this sec-
tion 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 straight-
forward as the approaches presented here. Most applications have
many more components — and many more connections — than the
illustrations show.
The simplifi ed 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 amplifi ers (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 909kΩ series resis-
tor. 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 simplifi ed 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 appropri-
ate 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
(IOL) 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 no-clean solders.
8. Suggested Mating Connectors:
Panel mounted:
Connector housing Murata Power Solutions P/N 4320-01069-0
Terminal type Murata Power Solutions P/N 4400-01032-0
Crimping tool Murata Power Solutions 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 Murata Power Solutions P/N 4320-01074-0
1
12
3
+5V SUP
(–) IN LO
5V RET
11
(+) IN HI
6
DP1
+
–
AC to DC Converter
VIN
DMS-30PC-1
8
7
REF OUT
REF IN
85-264Vac
DMS-30PC Series
3½ Digit, LED Display Low-Power,
Miniature Digital Panel Voltmeters
MPM_DMS_30PC.G01 Page 3 of 6
www.murata-ps.com/support
APPLICATIONS
Figure 3. Differential Input Confi guration
R2
R1 + R2
x VIN = Reading
50kΩ < R1 + R2 < 10MΩ
Figure 6. Floating Input Measurements
(Alternate Confi guration)
Figure 5. Floating Input Measurements
Figure 4. Input Attenuation Circuit
10 (ANALOG COMMON) or pin 3 (5V RETURN) to (–) INPUT LO (pin 12)
provides the reference point for the meter's input.
A "fl oating" input is a signal that has no galvanic connection to the
meter's power supply. In the fi gures below, the 1.5V battery illustrates
a true fl oating input.
RShunt = R1 = VFsr /IFsr
Where: VFsr = 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:
2. Differential Input Confi gurations: Differential measurements can
be made with all DMS-30PC meters. Figure 3, though not a practi-
cal 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 attenu-
ated. 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-fi lm resistors with absolute TCR's
less than 50ppm/°C. See Ap Note 4 for more information on engineer-
ing scaling.
4. Floating Signal Source Measurements: Floating signals can be
measured using the circuits shown in Figures 5 and 6. Connecting pin
1
12
3
+5V SUP
(–) IN LO
5V RET
11
(+) IN HI
6
AC to DC Converter
R2
R1
R3
1k
1k
1k
8
7REF IN
DP1
REF OUT DMS-30PC-1
85-264Vac
R2
11
12
(+) IN HI
(–) IN LO
VIN
R1
+
–
13
+5V SUP 5V RET
AC to DC Converter
8
7
REF OUT
REF IN
DMS-30PC-1
85-264Vac
13
+5V SUP 5V RET
6
DP1
AC to DC Converter
DMS-30PC-1
12
(–) IN LO
11
(+) IN HI
1.5V
CELL
+
–
8
REF OUT
REF IN
7
85-264Vac
13
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
AC to DC Converter
85-264Vac
DMS-30PC Series
3½ Digit, LED Display Low-Power,
Miniature Digital Panel Voltmeters
MPM_DMS_30PC.G01 Page 4 of 6
www.murata-ps.com/support
APPLICATIONS
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 50kΩ 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 RShunt 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), VFsr = 1.000 Volts
RShunt = 1.000V/(0.020 – 0.004)A
R
Shunt = 1.000V/0.016A = 62.5 Ohms
6. Power 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 confi gured
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 regula-
tor manufacturer's data sheet to ensure the regulator is being utilized
safely and correctly.
7. Digital Ammeter: Digital ammeters are fi nding 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 voltme-
ters. 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 0.1Ω current shunt. The circuit shown represents
a basic ammeter connection diagram. A detailed application note
describing digital dc ammeters is included in Murata Power Solutions'
new Digital Panel Meter Databook.
8. External Gain Adjustment: Connect REFERENCE OUT
(pin 8) to REFERENCE IN (pin 7) for normal, factory calibrated, opera-
tion. Use the +1.23V REFERENCE OUT (pin 9) for applications needing
external gain adjustment. Figure 10 shows the wiring confi guration
for each model. Calibration is performed with a precise, near-full-
scale, input voltage.
13
5V RET
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
85-264Vac
DMS-30PC-2-RL
5
712
+
–
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
+
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
RShunt
Load
(3.3 )
12
(–) IN LO
W
W
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
VOLTAGE
CALIBRATOR
OUT
COM
DMS-30PC Series
3½ Digit, LED Display Low-Power,
Miniature Digital Panel Voltmeters
MPM_DMS_30PC.G01 Page 5 of 6
www.murata-ps.com/support
APPLICATIONS
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)
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)
#2-56 INSERT
0.156 (3.96) DEEP
FRONT VIEW 1.270
(32.26)
0.187
(4.75)
DMS-BZL1 and DMS-BZL2
2.35 (59.69)
2.118 (53.80)
0.093 (2.362) DIAMETER (4 REQUIRED)
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)
DMS-BZL1 & BZL2
PANEL CUTOUT
MADE IN USA
BEZEL INSTALLATION
PANEL
BEZEL
GASKET *
* Sealing gasket is supplied with the DMS-BZL2 and DMS-BZL4
MADE IN USA
®
RETAINING CLIP INSTALLATION
PANEL
BEZEL INSTALLATION AND RECOMMENDED DRILL AND PANEL CUTOUT
MECHANICAL SPECIFICATIONS
DMS-30PC Series
3½ Digit, LED Display Low-Power,
Miniature Digital Panel Voltmeters
MPM_DMS_30PC.G01 Page 6 of 6
www.murata-ps.com/support
Murata Power Solutions, Inc. 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. Specifi cations are subject to change without
notice. © 2015 Murata Power Solutions, Inc.
Murata Power Solutions, Inc.
11 Cabot Boulevard, Mansfi eld, MA 02048-1151 U.S.A.
ISO 9001 and 14001 REGISTERED
This product is subject to the following operating requirements
and the Life and Safety Critical Application Sales Policy:
Refer to: http://www.murata-ps.com/requirements/
