DPM950

3½ Digit LCD Voltmeter 

## DPM 950 

Very low current consumption results in a long battery life and makes the DPM 950 ideal for portable equipment. For low light viewing, a long life LED backlight is fitted. The meter is housed in a robust carrier which can be bolted in place or panel mounted using the bezel, windowandclipsprovided. 

- **19mm (0.75“) Digit Height** 

- **IDC Interface** 

- **Auto-zero** 

- **Auto-polarity** 

- **200mV d.c. Full Scale Reading (F.S.R.)** 

- **LED Backlight** 

- **Single Rail Version** 

- **Alarm Annunciator** 

## **SCALING** 

Two resistors Ra and Rb may be fitted in order to alter the fullscalereading(F.S.R.)ofthemeter-seetable. Themeterwillneedre-calibration. 

|**Required F.S.R.**<br>2V<br>Note|**Ra**<br>910k|**Rb**<br>100k|
|---|---|---|
|20V<br>Note|1M|10k|
|200V<br>Note|1M|1k|
|2kV<br>Note|1M|100R|
|200 A|LINK|1k|
|2mA|LINK|100R|
|20mA|LINK|10R|
|200mA|LINK|1R|



## **NOTE** 

EnsurethatLink10isopeniffittingRa. 

|**Specification**<br>~~es~~|**Specification**<br>~~es~~|**Min.**<br>~~es~~<br>~~es~~|**Typ.**<br>~~es~~|**Max.**<br>~~es~~|**Unit**<br>~~es~~|
|---|---|---|---|---|---|
|Accuracy (overall error)**<br>Linearit<br>~~es~~<br>~~Ss~~<br>~~es~~||~~es~~<br>~~es~~<br>~~Ss~~<br>~~es~~|0.05<br>~~es~~<br>~~Ss~~<br>~~es~~|0.1<br>±1<br>~~es~~<br>~~Ss~~<br>~~es~~|%(±1 count)<br>~~es~~<br>~~Ss~~<br>~~es~~|
|Linearity<br>~~es~~||~~es~~|~~es~~|±1<br>~~es~~|count<br>~~es~~|
|Sample rate<br>~~Ss~~||~~Ss~~|3<br>~~Ss~~|~~Ss~~|samples/sec<br>~~Ss~~|
|Operatingtemperature range<br>~~es~~<br>~~Ph~~||0<br>~~es~~<br>~~es~~|~~es~~|50<br>~~es~~|°C<br>~~es~~|
|Temperature s<br>tability<br>~~es~~<br>~~Ph~~||~~es~~<br>~~es~~<br>~~f+~~|100<br>~~es~~<br>~~f+—f+~~|~~es~~<br>~~—f+~~|ppm/°C<br>~~es~~|
|Supply<br>(V+ to V-)<br>voltage<br>~~Ph~~<br>~~ee~~|DPM 950<br>~~Ph~~<br>~~ee~~|7.5<br>~~es~~<br>~~f+~~<br>~~ee~~<br>|9<br>~~f+—f+~~<br>~~ee~~<br>|14<br>~~—f+~~<br>|V<br>~~ae~~|
||DPM 950S<br>~~Ph~~<br>~~ee~~<br>~~ee~~|3.5<br>~~es~~<br>~~f+~~<br>~~ee~~<br>~~ee~~<br>~~ee~~|5<br>~~f+—f+~~<br>~~ee~~<br>~~ee~~<br>~~a~~|6.5<br>~~—f+~~<br>~~ee~~<br>~~a~~||
|Supply current<br>(not includingbacklight) <br>~~ee~~|DPM 950<br>~~ee~~|~~f+~~<br>~~ee~~<br>~~ee~~<br>~~ee~~|150<br>~~f+ —f+~~<br>~~ee~~<br>~~a~~<br>~~ee~~|~~—f+~~<br>~~a~~|A<br>~~ae~~|
||DPM 950S<br>~~ee~~<br>~~es~~|~~ee~~<br>~~ee~~<br>~~es~~<br>~~ee~~|500<br>~~ee~~<br>~~a~~<br>~~es~~<br>~~ee~~|~~a~~<br>~~es~~||
|Backlight current *<br>~~ee ~~<br>~~es~~<br>~~Ge~~||~~ee ~~<br> ~~ee ~~<br>~~ee~~<br>~~es~~<br>~~Ge~~|50<br> ~~ee~~<br> ~~a~~<br>~~ee~~<br>~~es~~<br>~~eS~~|~~a ~~<br>~~es~~|mA<br> ~~ae~~<br>~~es~~|
|Input leakage current (Vin = 0V)<br>~~Ss~~<br>~~Ge~~||~~Ss~~<br>~~Ge~~|1<br>~~Ss~~<br>~~eS~~|10<br>~~Ss~~|pA<br>~~Ss~~|



- Supply voltage 5V nom. 

- ** To ensure maximum accuracy, re-calibrate periodically. 

## **CONNECTOR SOURCING GUIDE** 

**==> picture [533 x 318] intentionally omitted <==**

**----- Start of picture text -----**<br>
CO ———— METHOD Cable Mounting IDC Supplied With Product<br>DIMENSIONS All dimensions in mm (inches) Panel cut-out 72 x 40 (2.83 x 1.57)<br>Maximum panel thickness 3mm (0.12).<br>76.0 (2.99)<br>a<br>72.5 (2.85) 51 (2.01)<br>Display in Test Mode REAR<br>VIEW<br>a. 1.0 (0.04)<br>b. 2.0 (0.08)<br>c. 6.5 (0.26)<br>d. 11.5 (0.45)<br>~ 51.0 (2.01) a e. 8.4 (0.33)*<br>b c<br>*typical depth of tallest component behind PCB,<br>this dimension is for guidance only.<br>61.5 (2.42)<br>d e<br>51.0 (2.01) Ø5.7<br>(0.22)<br>11<br>2 3 4 1 ON BOARD<br>SOLDER LINKS<br>rn === H |<br>Ra 12<br>Rb<br>10<br>SCALING RESISTORS<br>| [| © | ,s8eesesecoc0o0G REARVIEW DP2 N DP3 LJ<br>DP1<br>71.5 (2.81) Ø3.0<br>J (0.12)<br>Specifications liable to change without prior warning DPM 950 Issue 11 06/2010 S.L. Applies to DPM 950/4<br>(0.94)<br>(1.73) (1.59) (0.94) 24<br>44.0 40.5 24.0<br>(1.54) (0.94) (0.96)<br>39.0 24.0 24.5<br>HI HI<br>LP+ V+ TEST IN N.C. REF DP1 DP3<br>LP- V- -5V INLO COM LOREF XDP DP2<br>**----- End of picture text -----**<br>


**LASCAR ELECTRONICS LTD. LASCAR ELECTRONICS INC. LASCAR ELECTRONICS (HK) LTD. MODULE HOUSE, WHITEPARISH, 4258 WEST 12th STREET, 8th FLOOR, CHINA AEROSPACE CENTRE, 143 HOI BUN WILTSHIRE SP5 2SJ UK ERIE, PA 16505 USA ROAD, KWUN TONG, KOWLOON, HONG KONG TEL: +44 (0)1794 884567 FAX: +44 (0)1794 884616 TEL: +1 (814) 835 0621 FAX: +1 (814) 838 8141 TEL: +852 2389 6502 FAX: +852 2389 6535 E-mail: sales@lascar.co.uk E-mail: us-sales@lascarelectronics.com E-mail: saleshk@lascar.com.hk** 

## **PIN FUNCTIONS** 

1. LPNegativepowersupplytoLEDbacklighting. 

2. LP+ PositivepowersupplytoLEDbacklighting. 

3. V- Negativepowersupplyconnection. 

4. V+ Positivepowersupplyconnection. 

5. -5V Outputfromnegativerailgeneratorcircuit. ThisoutputisaninversionofV+(DPM950Sonly). 

6. TEST ConnecttoV+todisplayallsegmentsexceptDPs. ItshouldnotbeoperatedformorethanafewsecondsastheD.C.voltageappliedto theLCDmay'burn'thedisplay. Thispinisnormallyat5VbelowV+andisthegroundforthedigitalsectionofthemeter. Itcanbe usedtopowerexternallogicuptoamaximumof1mA. 

7. INLO Negativemeasuringdifferentialinput. Analogueinputsmustbenocloserthan1Vtoeitherpositiveornegativesupply.Thenegative 8. INHI Positivemeasuringdifferentialinput. supplyoftheDPM950Sisgeneratedinternallyandmirrorsthepositivesupplyvoltage. 

9. COM GroundfortheanaloguesectionoftheA/Dconverter,itisactivelyheldatapproximately2.8VbelowV+andmustnotbeallowedto sinkexcessivecurrent(>100 A)by,forinstance,connectingtoahighervoltage. 

11. REFLO Negativeinputforreferencevoltage. CanbeconnectedtoCOMvialink3. 

12. REFHI Positiveinputforreferencevoltage. Connectedvialink1tointernalreference. 

13. XDP AnnunciatorDriveWaveform,thisisaninversionofthebackplane. 

14. DP1 199.9 

15. DP2 19.99 ConnecttoV+todisplayrequiredDecimalPointorshortcorrespondingDPlink. 

16. DP3 1.999 

- 18&32.BP LCDbackplanedrivewaveform. 

23. REFNegativeoutputfrominternalreference. 

24. REF+ Positiveoutputfrominternalreference. 

25. LO BAT Used to control the low battery annunciator externally, cut link 12 and take to V+ to turn on annunciator. The annunciator turn on point can also be set by adjusting the BAT potentiometer (R10), in which case do not connect to this pin and leave link 12 intact. 

26. REF BG Output from internal bandgap reference. (Factory fitted option.) 27. . Alarmannunciator,cutlinkALMandtaketoXDPtodisplay. 28. : Colonannunciator,cutlinkCOLandtaketoXDPtodisplay. 29. - Polarityannunciator,connectedvialink11topolarityoutputofIC1. Cutlink11andeithertaketoXDPto displayormakeothersideoflink11toholdoff. 

Only Pins 1-16 are fitted, these functions are available but a connector is not provided. 

30. POL PolarityoutputofIC1. 

31. CLK Maybeusedtooverridetheinternaloscillatorandcontrolthesamplerate. Link14mustthenbemade. 

## **SAFETY** 

To comply with the Low Voltage Directive (LVD 93/68/EEC), input voltages to the module’s pins must not exceed 60Vdc. If voltages to the measuring inputs do exceed 60Vdc, then fit scaling resistors externally to the module. The user must ensure that the incorporation of the DPM into the user’s equipmentconformstotherelevantsectionsofBSEN61010(SafetyRequirementsforElectricalEquipmentforMeasuring,ControlandLaboratoryUse). 

**==> picture [526 x 304] intentionally omitted <==**

**----- Start of picture text -----**<br>
VARIOUS OPERATING MODES<br>Normally Normally<br>ON-BOARD LINKS: In order to quickly and easily change operating modes for different applications, SHORTED OPEN<br>the meterhasseveralon-boardlinks. Theyaredesignedtobeeasilyopened(cut)orshorted(soldered). CutOPENto SolderSHORTto<br>Do not connect more than one meter to the same power supply if the meters cannot use the same<br>signal ground. Taking any input beyond the power supply rails will damage the meter.<br>V+ V+ V+<br>4 4 4<br>V+ V+ V+<br>8 8<br>±200mV + 8 IN HI ±200mV +- 7 IN LOIN HI 14V max7V min ±200mV +- 7 ININ HI LO<br>- 7 IN LO<br>0V<br>V- V- V-<br>3 1V min 3 3<br>1a V- V- a V-<br>Check Links 2 & 3 are SHORTED. Check Link 3 is SHORTED. Check Link 3 is SHORTED.<br>Measuring a floating voltage source Split rail supply (DPM 950) Measuring a single ended input<br>of 200mV full scale. V+ referenced to supply (DPM 950S).<br>V+ 4 V+<br>4 + 8 V+ IIN 4<br>8 IN HIV+ V1 - 7 IN LOIN HI 220k 8 IN V+HI<br>R<br>12<br>7 IN LO V2 +- 11 REF HIREF LO 6R2 5k ZeroSet 97 IN LO<br>R= I [0.2] FSR V- COM<br>V- 3 IOUT V-<br>3 V- 3<br>Qo V- Check Links 1 & 4 are OPEN. f f V-<br>Check Links 2 & 3 are SHORTED. Measuring the ratio of two voltages. Check Link 3 is SHORTED.<br>Measuring current. Supply MUST Reading = 1000 V1/V2 Measuring 4-20mA to read 0-999<br>be isolated. 50mV < V2 <200mV V1< 2V2. (supply MUST be isolated).<br>**----- End of picture text -----**<br>


_**Specifications liable to change without prior warning**_ 

**DPM 950 Issue 11 06/2010** 

**Applies to DPM 950/4** 

**S.L.**