LASCAR DPM340 User Manual

DPM 340 Miniature 3½ Digit LED Voltmeter

A very compact low-cost LED module ideally suitedfor applications where a brightdisplay under all conditions isrequired. The DPM 340
is fittedwith high efficiency, very low current LEDs and is housed in acarrier with integral snap-in bezel. The smallsize and lowcost of the
unit makes it very suitable forhighvolumeOEMapplications.

8mm (0.31") Digit Height

Programmable Decimal Points

Auto-zero, Auto-polarity

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

Very Low Current Consumption

SCALING

Two resistors Ra and Rb may be used in order to
alter the full scale reading (F.S.R.) of the meter - see
table.

+

Ra

INPUT

Rb

-

IN HI

IN LO

Required F.S.R. Ra Rb

2V 910k 100k
20V 1M 10k
200V 1M 1k
2kV 1M 100R
200 A LINK 1k

µ

2mA 100R
20mA 10R
200mA 1R

The meter will need re­calibration by adjusting
the on-board
potentiometer.

LINK
LINK
LINK

Stock Number

Standard Meter DPM 340

Specification Min. Typ. Max. Unit

Accuracy (overall error) * 0.05 0.1 % (±1 count)
Linearity ±1 count
Sample rate 3 samples/sec
Operating temperature range 0 50 °C
Temperature s 150 ppm/°C
Supply 4.75 5 5.25 V
Supply current** 50 65 mA
Input leakage current (Vin = 0V) 1 10 pA

* To ensure maximum accuracy, re-calibrate periodically.
** Depends on reading.

tability

voltage

DIMENSIONS

12.7 (0.50)

20.0 (0.79)

17.5 (0.69)

All dimensions in mm (inches)

40.0 (1.57)

27.3 (1.07)

e

DP COM

11

fg

IN HI

RHI

DP1

DP2

IN LO

+5V

DP3

37.5 (1.48)

COM

RLO

0V

1

h

abcd

a. 2.00 (0.08)
b. 6.00 (0.24)
c. 1.60 (0.06) max
d. 6.00 (0.24)
e. 2.54 (0.10)
f. 0.50 (0.02)
g. 6.00 (0.23)
h. 2.00 (0.08)

11

Panel cut-out

38.0 x 18.0 (1.50 x 0.71)

Panel thickness

1.0 to 2.5 (0.04 to 0.1)

ON BOARD SOLDER LINKS

Lref

DP1

DP2

DP3

1

PANELFITTING

Locate the meter by passing it through the front of the panel cut-out and gently push until the rear of the bezel is flush with the panel (DO NOT
PUSH ON THE DISPLAY AREA). The snap-in lugs will now automatically hold the meter firmly in position.

http://www.lascarelectronics.com

LASCAR ELECTRONICS LTD.

MODULE HOUSE, WHITEPARISH,

TEL: [phone] FAX: [phone]

WILTSHIRE SP5 2SJ UK

E-mail: [e-mail]

LASCAR ELECTRONICS INC.

3750 West 26th Street,

TEL: [phone] FAX: [phone]

Erie, PA 16506 USA

E-mail: [e-mail]

LASCAR ELECTRONICS (HK) LIMITED

FLAT C, 5/FL., LUCKY FTY. bldg., 63-65 HUNG TO ROAD

KWUN TONG, KOWLOON, HONG KONG

TEL: [phone] FAX: [phone]

E-mail: [e-mail]

PIN FUNCTIONS

1. 0V Negative powersupplyinput.

2. RLO Negative inputforreferencevoltage.

3. RHI Posi

4. IN HI Positivemeasuring input.

5. COM The groundfortheanalogue sectionofthe converter,heldactivelyat 3.05V(nom)below +5V. This pinis foruseonly whenthe module

6

. IN LO Negative measuringinput.

7. +5V Positive powersupplyinput.

8. DP3 1.999

9. DP2 19.99 Connect requiredDPpinto DPCOM.

10. DP1 199.9

11. DP COM Connect torequireddecimalpoint (DP1,DP2or DP3)to illuminate.

tive inputforreferencevoltage.

is usedwithafully floatingsupply.

It shouldonnoaccount beconnected toanyother terminationsorcircuitryexceptas specifiedin therelevantoperating modes.

This pinisnotfitted asstandardto theDPM 340.

Note:

A negativesupplyisgenerated internallyandmirrorsthe positivesupply. Forexample: ifV+ is+5V, then the internally
generated V-is -5V. When measuringwith theinputreferenced tothesame supplyrail asthatof thepanel meter, thenthelimitationson
the inputrangeare(V- + 1.5V)to(V+- 1.5V).

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 equipment conforms to the relevant sections of BS EN 61010 (Safety Requirements for Electrical Equipment for
Measuring, Control and Laboratory Use).

VARIOUS OPERATING MODES

+5V

7

+5V

4

INPUT
VOLTAGE

+

-

6

IN HI

IN LO

0V

RLO

COM

1

2

5

0V

Operation with input referenced to panel
meter supply (single ended).

R

0.2

R=

FSR

I

4

6

5

IIN

220k

6R2

SET

5k

ZERO

IOUT

Measuring 4-20mA to read 0-999.

+5V

7

+5V

IN HI

IN LO

COM

COM

0V

RLO

1

2

5

0V

4

6

5

IN HI

IN LO

COM

7

+5V

RLO

COM

0V

1

INPUT
VOLTAGE

+5V

0V

4

2

5

INPUT
VOLTAGE

+

6

-

5

Operation with input floating with respect to
power supply.

7

+5V

180k

4

+

-

6

IN HI

IN LO

3

RHI

15k

2

RLO

COMCOM

0V

1

0V

2k

55

+5V

22k

8069

IN HI

IN LO

COM

+5V

COM

0V

7

RLO

1

+5V

0V

Measuring current.

Adding an external reference.

1. Cut Link Lref

2. Fit components as indicated above.

Specifications liable to change without prior warning DPM 340 Issue 5 August/2002 M.C. Applies to DPM 340/3