V1
3½ Digit LCD Voltmeter Module
PRODUCT DESCRIPTION
This low cost compact LCD voltmeter module is ideally suited for high volume applications. It features an exceptionally large
display in a miniature package and includes auto-zero and user-selectable decimal points. The module is supplied with a
panel mounting bezel.
FEATURES
• Low Cost
• 6.3mm (0.25") Digit Height
• 200mV d.c. Full Scale Reading
• 1mA (typ)@ +9V d.c. Power Supply
• Auto-zero and Auto-polarity
• User Selectable Decimal Points
• Supplied with Mounting Bezel
REAR VIEW
8
1
TYPICAL APPLICATIONS
ORDERING INFORMATION
• High Volume, Low Cost Systems
• Power Supply Monitoring
• Panel-Mount Indication
Stock Number
V1
Standard Meter
ELECTRICAL SPECIFICATIONS
Specification
Accuracy (overall error) *
Linearity
Min.
Max.
0.25
±3
±5
3
0-1000 reading
0-2000 reading
Sample rate
Operating temperature range
Temperature stability
Supply voltage
Supply current
Typ.
0
7.0
50
300
9
1
12
2
Unit
% (±3 counts)
counts
counts
samples/sec
°C
ppm/°C
V d.c.
mA
* To ensure maximum accuracy, re-calibrate periodically.
SAFETY
To comply with the Low Voltage Directive (LVD 93/68/EEC), input voltages to the module’s pins must not exceed
60Vdc. The user must ensure that the incorporation of the panel meter 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).
LASCAR ELECTRONICS LTD.
MODULE HOUSE,
WHITEPARISH,
WILTSHIRE SP5 2SJ,
UK
TEL: +44 (1794) 884567
FAX: +44 (1794) 884616
E-mail: sales@lascar.co.uk
LASCAR ELECTRONICS INC.
4258 WEST 12th STREET,
ERIE,
PA 16505,
USA
TEL: +1 (814) 835 0621
FAX: +1 (814) 838 8141
E-mail: us-sales@lascarelectronics.com
www.lascarelectronics.com
LASCAR ELECTRONICS (HK) LTD.
8th FLOOR, CHINA AEROSPACE CENTRE,
143 HOI BUN ROAD,
KWUN TONG, KOWLOON,
HONG KONG
TEL: +852 2389 6502
FAX: +852 2389 6535
E- mail: saleshk@lascar.com.hk
Page 2 of 4
No: 695 -Page 1 of 4
V1
3½ Digit LCD Voltmeter Module
DIMENSIONS
14.0 (0.55)
Panel thickness: 1.0 - 3.0
(0.04 - 0.12)
38.0 (1.50)
30.0 (1.18)
5.5 (0.22)
1.6 (0.06)
8.0 (0.31)
All dimensions in mm (inches)
2.54
(0.1)
18.0 (0.71)
23.0 (0.91)
dia 2.5 (0.1)
38.0
(1.50
)
21.0 (0.83)
15.0 (0.59)
34.0(1.34)
31.0(1.22)
2.5(0.1) dia
PANEL FITTING
Panel
Fixing Clip
Meter
Fastener
Bezel
1
2
FUNCTIONAL BLOCK DIAGRAM
3
4
PIN CONFIGURATION
(rear view)
V+
Vref
REAR VIEW
1
V+
VINHI
INLO
CAL
COM
4
INHI
CAL
L1
8
XDP
A/D
+
_
5
XDP
DP1
DP2
DP3
INLO
V-
DP3 2 1
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Page 2 of 4
No: 695 -Page 2 of 4
V1
3½ Digit LCD Voltmeter Module
CIRCUIT DIAGRAM
V+
INHI
INLO
1
R2
1M
3
4
R1
180k
C1
100nF
27
28
29
C2
220nF
31
C3
100nF
30
32
L1
C4
100nF
34
33
35
V+
36
R6
100k
40
R3
100k
39
38
R5
3k
C5
100pF
INT
1
V+
BUF
A/Z
IN HI
IN LO
COM
CREF+
CREFREF LO
REF HI
OSC1
OSC2
OSC3
IC1
a1
b1
c1
d1
e1
f1
g1
a2
b2
c2
d2
e2
f2
g2
a3
b3
c3
d3
e3
f3
g3
bc4
5
4
3
2
8
6
7
12
11
10
9
14
13
25
23
16
24
15
18
17
22
19
12
11
10
9
15
13
14
19
18
17
16
21
20
7
24
23
5
22
4
25
2
26
27
29
1
30
20
POL
21
V- TEST BP
37
26
a1
b1
c1
d1
e1
f1
g1
a2
b2
c2
d2
e2
f2
g2
a3
b3
c3
d3
e3
f3
g3
b4
c4
POL
COM
COM
DP1
199.9
8
6
DP2
19.99
6
7
DP3
1.999
3
8
DP1
LCD1
LOBAT
R9
1M
R8
1M
DP2
DP3
R7
1M
28
V+
R4
1.5k
V-
R10
100k
R11
100k
Q1
3904
2
5
XDP
PIN FUNCTIONS
1.
2.
3.
4.
5.
6.
7.
8.
V+
VINHI
INLO
XDP
DP1
DP2
DP3
Positive power supply connection.
Negative power supply connection.
Positive measuring input with reference to IN LO.
Analogue inputs must be no closer than 1V
to either the positive or negative supply.
Negative measuring input with reference to IN HI.
Connect to DP1, 2 or 3 to display required decimal point.
Connect to XDP to display Decimal Point 1 (199.9).
Connect to XDP to display Decimal Point 2 (19.99).
Connect to XDP to display Decimal Point 3 (1.999).
Solder Links:
L1
Normally Closed, connects COM to INLO.
www.lascarelectronics.com
No: 695 -Page 3 of 4
V1
3½ Digit LCD Voltmeter Module
SCALING
Two resistors Ra and Rb
may be used to alter the
full scale reading (FSR) of
the meter - see table. The
meter will have to be recalibrated by adjusting the
calibration potentiometer
on the rear of the module.
Voltage
Vin
Current
Iin
FSR
2V
20V
200V
2000V*
200mA
2mA
20mA
200mA
Ra
910k
1M
1M
1M
0R
0R
0R
0R
Rb
100k
10k
1k
100R
1k
100R
10R
1R
Ra
+
INHI
Vin or Iin
Rb
-
INLO
*Ensure that Ra is rated for high voltage use.
APPLICATIONS
Do not connect more than one meter to the same power supply
if the meters cannot use the same signal ground. Taking any
input beyond the power supply rails will damage the meter.
Normally
SHORTED
Cut to
OPEN
Normally
OPEN
Solder to
SHORT
+7.0 to +12V
+
3 IN
-
4
1
1
V+
V+
L1
DP1
HI
±200mV
IN LO
+7.0 to +12V
XDP
V1
6
5
I+
3 IN
I-
4
L1
DP1
HI
IN LO
V-
XDP
V1
6
5
V-
2
2
0V
0V
Measuring an input voltage referenced to a floating supply,
i.e. the input voltage and the meter's power supply are
isolated from each other. Check Link L1 is closed.
Measuring a current referenced to a floating supply, i.e. the
current being measured and the meter's power supply are
isolated from each other. Check Link L1 is closed.
+3.5 to +6.0V
1
V+
+
±200mV
-
3
4
L1
DP1
IN HI
IN LO
V1
XDP
6
5
V-
2
-3.5 to -6.0V
Measuring a single ended input referenced to supply, i.e.
the input voltage and the meter's power supply share the
same 0V rail. Check Link L1 is open.
Specifications liable to change without prior warning
V1
Issue 7
www.lascarelectronics.com
06/2010
S.L.
Applies to V 1/2
Page 4 of 4
No: 695 -Page 4 of 4