DMS-40PC MURATA-PS | Alldatasheet

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Ḥ (+) INPUT HI (–) INPUT LO ANALOG COMMON DP4 REFERENCE IN/OUT +5V SUPPLY DP 1 DP 2 DP 3 DC/DC CONVERTER 5V RETURN +5V –5V +5V 2.5V REF. DATA A/D CONVERTER0 Vdc 0.01μF DISPLAY HOLD DISPLAY TEST R2 is not used on ±2V (-1) models. R2 = 101k on ±20V (-2) models and 9.2k on ±200V (-3) models. 909k MPM_DMS-40PC.C03 Page 1 of 6 DMS-40PC Series 4½ Digit, LED Display Digital Panel Voltmeters For full details go to www.murata-ps.com/rohs www.murata-ps.com Technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000 DMS-40PC Series, 4½ Digit, LED Display, Miniature DPM’s are fully self-contained, component-like, plug-in meters that provide scientific-grade accuracy (typically ±2 counts or ±0.005% of full scale) and outstanding reliability at a very affordable price. Within its miniature (2.17” x 0.92” x 0.56”), epoxy-encapsulated package, each meter contains a precision reference circuit; a high-resolution, autozeroing, factory-calibrated A/D converter; and a large (0.52”/13.2mm), easy-to-read, LED display. LED’s are available in red, yellow and green colors. Red LED’s are also offered in high-intensity or low-power versions. The versatile design of the DMS-40PC Series assures trouble-free installation and long-term operation. Differential input voltage ranges include ±2V, ±20V and ±200V. Input impedance is a minimum 800kΩ. Non-inverting inputs are overvoltage protected to ±250V, and CMRR is typically 86dB (dc to 60Hz). The DMS-40PC's epoxy-encapsulated package has an integral bezel and color filter. The moisture and vibration-proof package is extremely rugged and well suited for harsh environments and extended temperatures. Devices are fully specified for 0 to +50°C operation. All models operate from a single +5V supply and typically consume 500mW. Low- power models, whose display is just as bright as standard models, typically consume 175mW. DISPLAY TEST and HOLD functions are standard on each meter, and a complete set of BCD outputs are optional for sending data to CPU's or remote displays.

FEATURES

N Precision, autozeroing, factory-calibrated A/D converter N Scientific-grade accuracy, ±2 counts N Miniature size: 2.17" x 0.92" x 0.56" 55mm x 23mm x 14mm N Large (0.52"/13.2mm) LED display N Choice of red, green or yellow colors N High-intensity or low-power red LED's optional N Single +5V supply (175mW for low-power models) N Epoxy-encapsulated, 12-pin DIP with built-in color filter and bezel N 3 differential input voltage ranges N DISPLAY HOLD and TEST functions N Optional BCD data outputs for CPU interface N 0 to +50°C temperature range

Performance/Functional Specifications Typical at TA = +25°C and supply voltage = +5V using the single-ended input circuit, unless otherwise noted. ~ 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. € BCD outputs are optional and must be specified in the part number. See Ordering Information. Includes high-intensity and BCD-output models. 1. ANALOG COMMON (Pin 10) : This pin is an internal, low-noise ground for the DMS-40PC. It is internally connected to pin 3 (5V RETURN). Do not connect pin 10 to either pin 3 or your system ground as this will create a ground loop and possibly result in errone- ous readings. 2. REFERENCE INPUT/OUTPUT (Pin 7) : This pin accesses the meter’s internal reference and is used during the factory calibration proce- dure. Pin 7 should be left open in most common applications. It can be used in certain “ratiometric” applications in which it is desirable for the meter’s reference to track an external reference. See Ap Note 3 in the DATEL Panel Meter Catalog for more details. 3. DISPLAY TEST (Pin 2) : Connecting pin 2 to ground (pin 3, 5V RETURN) will activate all LED segments, and the display will read “–18888” regardless of the actual applied input. To reduce self-heat- ing, the display should not be left in the “test” mode for more than 10 seconds. This pin should be left open if unused. Analog Inputs Min. Typ. Max. Units Full Scale Input Range: DMS-40PC-1 – ±2 – Volts DMS-40PC-2 – ±20 – Volts DMS-40PC-3 – ±200 – Volts Input Impedence: – DMS-40PC-1 100 1000 – MΩ DMS-40PC-2, -3 0.8 1 – MΩ Overvoltage Protection ~ – – ±250 Volts Common Mode Voltage Range – – ±2 Volts CMRR (dc to 60Hz) – 86 – dB Control Inputs  Decimal Pt. Placement (Pins 4-6, 8) Tie to pin 3 to activate Display Test (Pin 2) Tie to pin 3 to activate all segments Display Hold (Pin 9) Tie to pin 3 to hold last reading BCD Outputs € Logic Levels (1 LSTTL load max.): Logic “1” +2.4 – – Volts Logic “2” – +0.4 +0.8 Volts Performance Sampling Rate 2.5 reading per second Accuracy (3 minute warm-up): DMS-40PC-1 (Vin = +1.9V) – ±2 ±3 Counts DMS-40PC-2 (Vin = +19V) – ±3 ±4 Counts DMS-40PC-3 (Vin = +190V) – ±3 ±4 Counts Zero Reading (Vin = 0 Volts) “–001” “000” “001” Temperature Drift (0 = +50°C) DMS-40PC-1 – ±0.4 ±1 Cnts/°C DMS-40PC-2, -3 – ±0.4 ±1.5 Cnts/°C Power Supply Requirements Supply Voltage +4.75 +5.00 +5.25 Volts Supply Current: Standard Models  – +100 +140 mA Low-Power Models – +35 +50 mA Display Display Type and Size 4½ digit, 0.52"/13.2mm high LED Polarity Indication Autopolarity ("–" for negative Vin) Overrange Indication "–0000" (flashing) for negative Vin "0000" (flashing) for positive Vin Physical/Environmental Operating Temperature 0 – +50 °C Storage Temperature –20 – +75 °C Accessories: DMS-30-CP Panel cutout punch DMS-BZL1-C DMS-40 bezel assembly DMS-BZL2-C DMS-40 bezel assembly with sealing gasket MOLEX connector, decimal point solder pads and attenuation resistor pads. BCD Output Models: BCD outputs are only available on standard red meters. DMS-40PC-1-RS-BCD-C for ±2V input range DMS-40PC-2-RS-BCD-C for ±20V input range DMS-40PC-3-RS-BCD-C for ±200V input range DMS-40PC-1-RL-BCD-C for ±2V input range DMS-40PC-2-RL-BCD-C for ±20V input range DMS-40PC-3-RL-BCD-C for ±200V input range DMS-40PC - 1 - R S - C LED Color: GS = Standard Green RH = High-Intensity Red RL = Low-Power Red RS = Standard Red YS = Standard Y ellow Input Range: 1 = ±2V 2 = ±20V 3 = ±200V A panel-mount retaining clip is supplied with each model.

Ordering Information

Humidity (non-condensing) 0 – 95 % Case Material Polycarbonate Weight 0.75 ounces (21 grams) MPM_DMS-40PC.C03 Page 2 of 6 DMS-40PC Series 4½ Digit, LED Display Digital Panel Voltmeters Technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000www.murata-ps.com TECHNICAL NOTES

show up as unstable display readings. When an input signal, assumed to be exactly zero volts, has a 1mV (0.001V) ground-loop induced offset, it is displayed as “0010” on a ±2V input-range meter! DATEL’s new Digital Panel Meter Catalog contains an application note describing power sup- ply wiring and ground loop avoidance techniques. The DMS-40PC’s simplified schematic, shown in Figure 1, can be very useful when debugging a malfunctioning circuit, especially 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). Figure 1 shows that input signals applied to (–) INPUT LO and (+) INPUT HI must to be kept within the ±5V power-supply rails. Also note that only pin 11 has a current- limiting 909kΩ series resistor. High input voltages that have a common ground connection 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 more noteworthy features is that it shows some DMS-40PC internal voltage values and also 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 using digital multimeters to perform system-level measurements. The multimeter’s negative lead (usually the black one) must always be con- nected to pin 3 (5V RETURN). This is the only way accurate readings can be made, particularly if the meter is configured for a differential input and concerns arise regarding common-mode voltages. 1. Single-Ended Input Configurations : The DMS-40PC can measure single-ended signals with either positive or negative polarities. True single-ended inputs always have one of their two terminals at the same potential as the DMS-40PC’s 5V RETURN (pin 3). Single-ended inputs are usually derived from power supplies that have a common ground with the meter’s +5V supply. Figure 2 shows the recom- mended connections to be used with this type of input. Pin 12, (–) INPUT LO, is shown directly tied to ground. This connection to ground must be a separate wire or pc-board trace originating at V IN’s negative terminal. This hook-up will normally eliminate display instabilities and errors caused by ground-loop currents which can occur if (–) INPUT LO is tied to ground at, or near, pin 3. Hard wiring is preferable, however, you can exercise dynamic control over the location of the decimal point by employing drive circuits that are capable of sinking a minimum of 20mA at voltages less than +0.4 Volts. 6. Gain Adjust : There is a gain-adjust potentiometer on the back of each meter. It has approximately ±150 counts of adjustment range. Since these meters 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 adjust- ments are most effective when performed with higher level input signals. 7. Soldering Methods : All models in the DMS-40PC Series easily withstand most common wave soldering operations. We recom- mend, 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: DMS-40PC Series meters are high-precision versatile devices that can be used in many applications requiring a 0 to 19,999 count digital display. The application circuits chosen for this section are ones that 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. All inputs applied to DMS-40PC meters must be steady, dc values, otherwise the input itself may cause display instabilities. Due to their 4½ digit resolution, DMS-40PC meters must be wired with greater care than their 3½ digit counterparts. Correct power-supply and input-signal wiring — an absolute must! — helps eliminate ground-loop induced errors that Figure 2. Single-Ended Input Configuration

  1. DISPLAY HOLD (Pin 9) : For normal operation, this pin should be left

pin 9 to ground (pin 3, 5V RETURN).

  1. Decimal Point Placement : The location of the decimal point is user-

APPLICATIONS

  1. Engineering Scaling and Input Attenuation : In many applications, the input signal must be scaled, or divided down, before being applied to the DMS-40PC. In some situations, the input signal exceeds the full-scale range of the meter, and in other applications, a direct one-to-one relation does not exist between the input voltage and the desired display reading. For an example of the second situation, assume an input voltage of 1.0Vdc is required to display a reading of “7500” when applied to a ±2V input meter. An input divider circuit, constructed with two series resistors with an output-to-input ratio of 0.75, will scale the 1.0V signal down to 0.75V. Engineering scaling and input attenuation are discussed in Ap Note 4 of the DATEL Digital Panel Voltmeter Catalog. Compensating for inputs which have a zero offset is also discussed. 6. BCD Outputs (DMS-40PC-X-RS and -RL-BCD Models Only) : Models with a “-BCD” suffix have 12 extra output pins, labeled A through L (6 per side), that provide the following information: mul- tiplexed serial BCD data, digit drive, and polarity indication. The data present on pins A - L simultaneously drives the meter’s internal LED display. All functions on pins A - L are 5V CMOS compatible, however, they are only rated to drive one, 74LS series, TTL load. CMOS logic IC’s, for example 74HC or 74HCT series devices, should be used when more fan-out capability is required. As the timing diagram in Figure 5 indicates, 100Hz is the optimum display scan rate when the BCD outputs are used to drive external LED displays. Faster scan rates, while permissible, are not necessary. Slower scanning, however, may result in noticeable “flickering” of the display. Common anode LED’s, combined with a 74LS247 BCD to seven-segment decoder, is the simplest way of implementing an external display. A seventy-five to one-hundred Ohm resistor on each LS247 segment-drive output provides adequate display brightness. The functions of pins A - L are listed below: BCD DATA (pins I - L): Four lines are used for BCD (Binary Coded Decimal) data outputs, representing the numbers 0 - 9. Positive-logic convention (a high represents a “1”) is used. DIGIT DRIVE ( pins A - E): These five outputs, when gated with STROBE, can be used to direct the BCD DATA into external latches. DIGIT DRIVE outputs may also be connected directly to the bases of NPN transistors in remote-display configurations. The digits are scanned right-to-left, i.e., MSD (DIGIT 1 DRIVE) to LSD (DIGIT 5 DRIVE). BUSY (pin G): This is a status pin that goes high at the start of an ana- log-to-digital (A/D) conversion cycle and remains high until the conver- sion ends. STROBE (pin H): A string of five sequential, active-low, STROBE pulses are output (after BUSY goes low) indicating the end of a conversion and the availability of new data. The 5 STROBE pulses occur only once per conversion, or 2.5 times each second. STROBE can be used to latch the BCD data (on pins I - L) into external latches. Either edge can be used since STROBE (~ 5μsec wide) is active only in the center of the cor- responding DIGIT DRIVE and BCD DATA outputs. POLARITY (pin F): This pin, which is also used inside the DMS-40PC to drive the negative-sign segment, indicates whether the last input signal conversion was positive (POLARITY set high) or negative (POLARITY set low). POLARITY, unlike BCD DATA, is not multiplexed. For data latching purposes, POLARITY should be sampled during the STROBE pulse for digit 1 (most significant digit).

Figure 6. BCD Data Timing Diagram

5 Strobes Only Per Conversion

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: #2-56 INSERT 0.156 (3.96) DEEPFRONT 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 PANEL BEZEL RETAINING CLIP INSTALLATION PANEL B1 (LSB) B8 (MSB) STROBE BUSY MADE IN USA DMS-40PC-X-XX FRONT VIEW +5V SUPPLY DISPLAY TEST 5V RETURN DP3 DP2 DP1 (–) INPUT LO (+) INPUT HI ANALOG COMMON DISPLAY HOLD DP4 REFERENCE IN/OUT DP1 DP2 DP3 DP4 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) 0.10 (2.5) TYP. 0.040 (1.02) 0.17 (4.3) TYP. 0.50 (12.7) 0.84 (21.3) 0.92 (23.4) PIN #1 IDENTIFIER 0.560 (14.22) (LSD) DIGIT 5 (MSD) DIGIT 1 DIGIT 2 DIGIT 3 DIGIT 4 POLARITY A B C D E F L K J I H G INSIDE ROW (BCD MODELS ONLY) (BCD MODELS ONLY) 1.60 (40.6) 0.10 (2.5) TYP. A B C D E F L K J I H G INSIDE ROW (BCD MODELS ONLY) 0.040 (1.02) 0.325 (8.26) 0.290 (7.37) PIN 1 CALIBRATION POTENTIOMETER HOLE LOCATION 0.125 (3.175) DIAMETER (USE ONLY WHEN PC BOARD MOUNTING) MPM_DMS-40PC.C03 Page 6 of 6 DMS-40PC Series 4½ Digit, LED Display Digital Panel Voltmeters 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. Specifications are subject to change without notice. © 2008 Murata Power Solutions, Inc. USA: Mansfield (MA), Tel: (508) 339-3000, email: sales@murata-ps.com Canada: Toronto, Tel: (866) 740-1232, email: toronto@murata-ps.com UK: Milton Keynes, Tel: +44 (0)1908 615232, email: mk@murata-ps.com France: Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01, email: france@murata-ps.com Germany: München, Tel: +49 (0)89-544334-0, email: munich@murata-ps.com Japan: Tokyo, Tel: 3-3779-1031, email: sales_tokyo@murata-ps.com Osaka, Tel: 6-6354-2025, email: sales_osaka@murata-ps.com China: Shanghai, Tel: +86 215 027 3678, email: shanghai@murata-ps.com Guangzhou, Tel: +86 208 221 8066, email: guangzhou@murata-ps.com Singapore: Parkway Centre, Tel: +65 6348 9096, email: singapore@murata-ps.com Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356 www.murata-ps.com email: sales@murata-ps.com ISO 9001 and 14001 REGISTERED Technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000www.murata-ps.com 11/25/08