(R) (R) DMS-30PC Series 31/2 Digit, LED Display Low-Power, Miniature Digital Panel Voltmeters Actual Size Features * Large (0.56"/14.2mm) LED display * 7 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 +60C temperature range * Numerous "plug-on" application boards * Low cost 1 The DMS-30PC Series is a broad line of self-contained, fully operational, 31/2 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 and 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 application-specific instrument. +5V 12 V+ +5V SUPPLY (-) INPUT LO 1 0.01F -5V 2 DISPLAY TEST R2 R1 DC/DC CONVERTER 11 (+) INPUT HI V- 909k +2.0V 3 5V RETURN 0 Vdc 4 10 ANALOG COMMON A/D CONVERTER 1.23V REF. DATA 9 +1.23V REFERENCE OUT DP 3 1.82k 8 5 DP 2 REFERENCE OUT +5V 7 6 DP 1 REFERENCE IN 1 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. Figure 1. DMS-30PC Series Simplified Schematic 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 DMS-30PC 31/2 D I G I T , L E D D I S P L AY D I G I T A L PA N E L V O L T M E T E R S Performance/Functional Specifications Typical at TA = +25C and supply voltage = +5V using the single-ended input circuit, unless otherwise noted. Min. Typ. Max. Units Ordering Information ----- 200 2 20 200 ----- mV Volts Volts Volts DMS-30PC - 1 - R S 100 0.8 1000 1 --- M M Overvoltage Protection -- -- 250 Volts Common Mode Voltage Range -- -- 2 Volts CMRR (dc to 60Hz) -- 86 -- dB Analog Inputs Full Scale Input Range: DMS-30PC-0 DMS-30PC-1 DMS-30PC-2 DMS-30PC-3 Input Impedance: DMS-30PC-0, -1 DMS-30PC-2, -3 Input Range: 0 = 200mV 1 = 2V 2 = 20V 3 = 200V Available on the following models only: -GS (Standard Green) -RS (Standard Red) -RL (Low-Power Red) 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 Accuracy (3 minute warm-up): DMS-30PC-0 (VIN = +0.19V) DMS-30PC-1 (VIN = +1.9V) DMS-30PC-2 (VIN = +19V) DMS-30PC-3 (VIN = +190V) Zero Reading (VIN = 0 Volts) Temperature Drift (0 to +60C) +1.23V Reference Output (Pin 9) 2.5 samples per second ----- 1 1 2 2 2 2 3 3 Counts Counts Counts Counts "- 001" "000" "001" -- 0.15 0.3 Cnts/C +1.20 +1.23 +1.25 Volts +4.75 +5.00 +5.25 Volts --- +400 +150 +550 +225 mA mA --- +12 +60 +17 +100 mA mA Power Supply Requirements Supply Voltage Supply Current: Standard Models: Blue display All others Low-Power Models: Red display Green or orange display Display Type and Size 31/2 Digit LED, 0.56"/14.2mm high Polarity Indication Autopolarity ("-" for negative VIN) Overrange Indication Humidity (Non-condensing) Case Material Weight Panel cutout punch DMS-30 bezel assembly DMS-30 bezel assembly with sealing gasket 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 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 approximately +2V. This output should be buffered if used to drive external loads since sourcing more than 15A from pin 9 can affect both the initial accuracy and temperature drift of the meter. "-1_ _ _ " for negative VIN "1_ _ _ " for positive VIN Physical/Environmental Storage Temperature Accessories: DMS-30-CP DMS-BZL1 DMS-BZL2 RN-DMS A panel-mount retaining clip is supplied with each model. Display Operating Temperature: Blue display models All other models LED Color: AS = Standard Amber BS = Standard 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 0 0 --- +50 +60 C C -40 -- +75 C 0 -- 95 % 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. Polycarbonate 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. 0.75 ounces (21 grams) 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. 2 DMS-30PC 31/2 D I G I T, L E D D I S P L AY D I G I TA L PA N E L V O LT M E T E R S Applications 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. 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. 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. 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). 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. DMS-30PC-X-BS +0.3V max. 18mA 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. 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). 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. 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 VIN to (-) INPUT LO (pin 12). Ground-loop currents can cause unstable readings. 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 Terminal type Crimping tool Wire size Insulation diameter Stripping length DATEL P/N 39-2079400 DATEL P/N 39-2099090 DATEL P/N 39-2099000 22 to 26 AWG 0.062" (1.57mm) maximum 0.100 to 0.125" (2.54 to 3.17mm) Board mounted: Socket DATEL P/N 39-2359625 DMS-30PC-1 11 (+) IN HI 8 REF OUT + VIN - 12 (-) IN LO 7 REF IN 1 +5V SUP 120 VAC 6 DP1 3 5V RET DATEL UPA-5/500 AC to DC Converter Figure 2. Single-Ended Input Configuration 3 DMS-30PC 31/2 D I G I T, L E D D I S P L AY D I G I TA L PA N E L V O LT M E T E R S 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 5Vpowered meters. DMS-30PC-1 8 11 (+) IN HI REF IN 7 12 (-) IN LO DP1 6 3 5V RET 1 +5V SUP 120 VAC 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. R1 1k R2 1k 1.5V CELL - 7 REF IN 1 +5V SUP DATEL UPA-5/500 120 VAC DATEL UPA-5/500 + 11 (+) IN HI 1.5V CELL 8 REF OUT 10 ANA COMM 12 7 REF IN (-) IN LO 1 +5V SUP 3 5V RET 6 DP1 DATEL UPA-5/500 120 VAC R2 DMS-30PC-1 - 50k < R1 + R2 < 10M x VIN = Reading R1 + R2 AC to DC Converter + Figure 6. Floating Input Measurements (Alternate Configuration) DMS-30PC-1 11 (+) IN HI 8 REF OUT VIN 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: 12 (-) IN LO 7 REF IN 1 +5V SUP 120 VAC 6 DP1 Figure 5. Floating Input Measurements 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. - 3 5V RET AC to DC Converter Figure 3. Differential Input Configuration R2 8 REF OUT 12 (-) IN LO R3 1k AC to DC Converter R1 DMS-30PC-1 11 (+) IN HI + REF OUT Connecting pin 10 (ANALOG COMMON) or pin 3 (5V RETURN) to (-) INPUT LO (pin 12) provides the reference point for the meter's input. 3 5V RET DATEL UPA-5/500 AC to DC Converter RShunt = R1 = VFsr / I Fsr Figure 4. Input Attenuation Circuit Where: VFsr = Full scale reading (in Volts) I Fsr = Relative full scale current (in Amps) 4. Floating Signal Source Measurements: Floating signals can be measured using the circuits shown in Figures 5 and 6. 4 DMS-30PC 31/2 D I G I T, L E D D I S P L AY D I G I TA L PA N E L V O LT M E T E R S Applications protection features: reverse polarity, short circuit and thermal runaway. 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. 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 RShunt = 1.000V/0.016A = 62.5 Ohms 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. 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 RShunt accordingly. DMS-30PC-1 11 (+) IN HI 8 REF OUT 1 +5V SUP + 10 ANA COMM 4-20mA 8 REF OUT + 12 R1 DMS-30PC-0-YS 5Vdc 7 REF IN (-) IN LO 9 1.23V REF R2 - 1 5V SUP - 3 5V RET 3 5V RET 6 DP1 7 REF IN 11 (+) IN HI 12 (-) IN LO 50k 0.150V 1.5 Amp (Load Current) 120 VAC DATEL UPA-5/500 Load (3.3 ) 0.1 RShunt AC to DC Converter Figure 9. Basic DC Ammeter Circuit Figure 7. 4-to-20mA Current Loop Operation 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. 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 configured to allow power supply monitoring over the range of 4.5-18Vdc. The circuit in Figure 8 uses a low-drop-out, threeterminal 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 OUT 12 (+) IN HI 11 LM2931Z-5 IN + - COM DMS-30PC-2-RL + 22F 10V 3 5V RET 12 10 ANA COMM OUT GND DMS-30PC (-) IN LO 1 +5V SUP 4.5 - 18Vdc VOLTAGE CALIBRATOR 11 (+) IN HI 3 5V RET 8 NC 7 REF IN 8.45k, 1% 5 1k 10 to 20 Turns DP2 7 REF IN 8 REF OUT 12 (-) IN LO 1k 10 to 20 Turns Figure 8. 4.5-18V Power Supply Monitor 8.45k, 1% Figure 10. External Gain Adjustment 5 9 1.23V REF Connections for 2V, 20V and 200V models Connections for 200mV models DMS-30PC 31/2 D I G I T , L E D D I S P L AY D I G I T A L PA N E L V O L T M E T E R S Mechanical Specifications MECHANICAL DIMENSIONS: Inches (mm) TOLERANCES: 2 PL DEC 0.02 (0.51) 3 PL DEC 0.010 (0.254) P IN # 1 ID E N T IF IE R D M S -3 0 P C -X -X X M A D E IN U S A (R) RECOMMENDED PC BOARD FINISHED HOLE DIAMETER: 0.042 0.003 (1.067 0.076) C A L IB R A T IO N P O T E N T IO M E T E R H O L E L O C A T IO N F R O N T V IE W P IN 1 0 .2 6 0 (6 .6 0 ) + 5 V S U P P D IS P L A Y T E 5 V R E T U D D D L Y S T R N P 3 P 2 P 1 1 1 2 2 1 1 3 1 0 4 9 5 8 6 7 0 .2 5 0 (6 .3 5 ) D P 1 0 .1 2 5 (3 .1 7 5 ) D IA M E T E R (U S E O N L Y W H E N P C B O A R D M O U N T IN G ) (R) LEAD DIMENSIONS: 0.025 (0.635) x 0.025 (0.635) NOMINAL ( ) IN (+ ) IN A N A L + 1 .2 3 R E F E R E F E P U P U O G V R R E R E T L T H C E F N C N C O I O M E R E E M O N E N C E O U T O U T IN D P 3 D P 2 0 .9 2 (2 3 .4 ) 2 .1 7 (5 5 .1 ) 0 .8 4 (2 1 .3 ) 2 .0 9 (5 3 .1 ) 0 .5 6 0 (1 4 .2 2 ) 0 .0 4 0 (1 .0 2 ) 0 .2 5 (6 .4 ) T Y P . 0 .0 4 0 (1 .0 2 ) 0 .1 0 (2 .5 ) T Y P . 0 .1 7 (4 .3 ) T Y P . 1 .8 0 (4 5 .7 ) 0 .0 4 0 (1 .0 2 ) 0 .1 5 (3 .7 ) T Y P . 0 .5 0 (1 2 .7 ) OPTIONAL BEZEL (DMS-BZL1 and DMS-BZL2) FRONT VIEW #2-56 INSERT 0.156 (3.96) DEEP 0.187 (4.75) BEZEL INSTALLATION LENAP (R) 1.270 (32.26) E D A M NI A S U (R) LEZ B 2.55 (64.77) RECOMMENDED DRILL AND PANEL CUTOUT DIMENSIONS 0.116 (2.95) INTERNAL CORNER RADII: 0.032 (0.81) MAX. RETAINING CLIP INSTALLATION 1.07 (27.18) 0.878 (22.30) PANEL CUTOUT LENAP 2.118 (53.80) (R) (R) 2.35 (59.69) 0.093 (2.362) DIAMETER (4 REQUIRED) ONLY WHEN USING OPTIONAL BEZEL ASSEMBLY (R) (R) 0.096 (2.44) ISO 9001 R E G I S T E R E D 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 Data sheet fax back: (508) 261-2857 DS-0258D 1/98 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 Munchen, Germany Tel: 89-544334-0 DATEL KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-354-2025 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.