OEM 1
Ultra-Miniature, Low Power, LCD Voltmeter
The OEM 1 uses the latest miniaturisation techniques to produce a very compact 3 ½ digit LCD voltmeter. It is designed to be a
drop-in component in most medium and high volume applications, ranging from shirt-pocket instrumentation and integral
sensor indicators to measurement probes. The meter features 5.5mm digit height, 3 decimal points, auto-polarity, auto-zero,
200mV full scale reading and a very low current consumption. The user need only add a calibration circuit. Connection to the
module is via a row of pins.
5.5mm Digit Height
Selectable Decimal Points
Auto-zero
Auto-polarity
200mV d.c. Full Scale Reading (F.S.R.)
(when using 100mV reference)
SCALING
A potential divider may
be used to alter the full
scale reading (F.S.R.) of
the meter - see table
(using 100mV
reference).
+
Ra
1M
INPUT
5
10nF
6
Rb
-
IN HI
Stock Number
Standard Meter
IN LO
OEM 1
Specification
Required F.S.R.
2V
20V
200V
2kV*
200µA
2mA
20mA
200mA
Ra
910k
1M
1M
10M*
0R
0R
0R
0R
Accuracy (overall error) *
Linearity
Sample rate
Operating temperature range
Temperature stability
Supply voltage
Supply current
Input leakage current (Vin = 0V)
Rb
100k
10k
1k
1k
1k
100R
10R
1R
Min.
0
7
Typ.
0.1
3
200
9
150
1
SAFETY
The meter will have to be re-calibrated by adjusting the
externally fitted calibration potentiometer.
DIMENSIONS All dimensions in mm (inches)
12.0 (0.47)
9.0
(0.35)
15.2 (0.60)
5.0
(0.20)
21.0 (0.82)
3.70
(0.14)
50
14
10
The user must ensure that the incorporation of the OEM 1 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).
NOTE
1
±1
Unit
% (±1 count)
count
samples/sec
°C
ppm/°C
V
µA
pA
* To ensure maximum accuracy, re-calibrate periodically.
* Ensure that Ra is rated for high voltage use.
3.0
(0.12)
Max.
12
1.27
(0.05)
WEBSITE: http://www.lascarelectronics.com/
LASCAR ELECTRONICS LTD.
MODULE HOUSE, WHITEPARISH,
WILTSHIRE SP5 2SJ UK
TEL: +44 (0)1794 884567 FAX: +44 (0)1794 884616
E-mail: sales@lascar.co.uk
LASCAR ELECTRONICS INC.
LASCAR ELECTRONICS (HK) LIMITED
3750 West 26th Street,
Erie, PA 16506 USA
TEL: +1 (814) 835 0621 FAX: +1 (814) 838 8141
E-mail: us-sales@lascarelectronics.com
FLAT C, 5/FL., LUCKY FTY. bldg., 63-65 HUNG TO ROAD
KWUN TONG, KOWLOON, HONG KONG
TEL: +852 2797 3219 FAX: +852 2343 6187
E-mail: b4lascar@samsongroup.com.hk
PIN FUNCTIONS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
REF HI
REF LO
V+
COM
Positive input for reference voltage.
Negative input for reference voltage.
Positive power supply connection.
Ground for analogue section of the A/D converter, it is actively held at 2.8V below V+ and must not
be allowed to sink current in excess of 100µA by, for instance, connecting it to a higher voltage.
Positive measuring input.
Negative measuring input.
Negative power supply connection.
Connecting this pin to XDP will turn on the Low Battery warning annunciator.
199.9 Connect to XDP (Pin 12) to display decimal point 1.
19.99 Connect to XDP (Pin 12) to display decimal point 2.
1.999 Connect to XDP (Pin 12) to display decimal point 3.
Annunciator drive waveform for DP1, DP2, DP3 and BAT.
This is an inversion of the LCD backplane signal.
INHI
INLO
VBAT
DP1
DP2
DP3
XDP
APPLICATIONS
• Personal Gas Monitoring
• Radiation Dose Monitoring
• Medical Instruments
• Other Compact Applications
• Measurement Probes
VARIOUS OPERATING MODES
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.
+
1M
V+
3
5 IN HI V+
100K
1
REF HI
6 IN LO
2
REF LO
±200mV
3K
2K
COM
V7
1M
+
10nF
-
ADJUST
FOR
100mV
100K
REF HI 1
6 IN LO
2
REF LO
±200mV
10nF
-
V+
3
5
IN HI V+
0V
4
3K
2K
COM
V7
1V
min.
IIN
220K
1M
5
10nF
6R2
5K
V+
3
V+
IN HI
1
REF HI
6 IN LO
2
REF LO
V-
IOUT
V7
Split supply operation.
100K
V1
3K
2K
COM
4
ADJUST
FOR
100mV
V2
+
-
1M
5
10nF
6
1
+
-
3
V+
IN HI
V+
IN LO
REF HI
2 REF LO
V7
V-
V-
Measuring the ratio of two voltages.
Reading = 1000 V1/V2
50mV< V2<200mV
V1<2V2.
Measuring 4-20mA to read 0-999.
(supply MUST be isolated).
Specifications liable to change without prior warning
14V max
7V min
4
V-
Measuring a floating voltage source
of 200mV full scale.
ADJUST
FOR
100mV
OEM 1
Issue 6
August/2002
M.C.
Applies to OEM 1/2