DPM 1AS-BL 31/2 Digit Backlit LCD Voltmeter Module PRODUCT DESCRIPTION The DPM 1AS-BL features a 200mV d.c. measurement range with auto-zero and auto-polarity. Decimal points are user selectable. The DPM 1AS-BL features a negative rail generator which enables the meter to measure a signal referenced to its own power supply GND. LED backlighting ensures excellent readability under low light conditions. The design of the panel meter's housing allows the module to be easily snapped into a panel. The module's low cost means it will suit high and low volume applications. The DPM 1AS-BL is intended to replace the DPM 1, DPM 1S, DPM 1-BL and DPM 1S-BL in many applications, usually requiring only minor circuit modifications. FEATURES * 5.5mm (0.22") Digit Height * 200mV d.c. Full Scale Reading * 3.0 to 7.5V or 6.0 to 15.0V Operation * Auto-zero and Auto-polarity * Programmable Decimal Points * LED Backlighting TYPICAL APPLICATIONS ORDERING INFORMATION * Precision Instrumentation Systems * Power Supply Monitoring * Hand held instruments * Panel-Mount Indication * Low Power Voltage Measurement Stock Number DPM 1AS-BL Standard Meter ELECTRICAL SPECIFICATIONS Specification Min. Typ. Max. Accuracy (overall error) * 0.1 Linearity 1 Sample rate 2.5 Operating temperature range 0 50 Temperature stability 250 Meter supply voltage V+ to GND configuration 3.0 5.0 7.5 V+ to Vconfiguration 6.0 9.0 15.0** Meter supply current V+ to GND configuration 350 175 V+ to Vconfiguration Backlight supply voltage 4.75 5.0 *** Backlight supply current @ 5V d.c. 15 30**** Input leakage current (Vin = 0V) 1 10 * To ensure maximum accuracy, re-calibrate periodically. ** Operation of the meter beyond the maximum supply voltage rating may cause permanent damage to the meter. *** An external series resistor is required above 5V, see Applications. **** This specification linearly derates to 20mA @ 50C. Unit % (1 count) count samples/sec C ppm/C V d.c. V d.c. A A V d.c. mA pA Unless otherwise noted, specifications apply at TA=25C, Vsupply=5Vd.c. (fclock=48kHz) and are tested with the module configured for single ended input mode. 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. PO BOX 50727 PALO ALTO CA 94303-0727 USA TEL: +1 (650) 838 9027 FAX: +1 (650) 833 5432 E-mail: lascarus@pacbell.net www.lascarelectronics.com LASCAR ELECTRONICS (HK) LIMITED 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 Page 2 of 4 Page 1 of 4 DPM 1AS-BL 31/2 Digit Backlit LCD Voltmeter Module DIMENSIONS All dimensions in mm (inches) 30.0 (1.18) c b d 1.26 (0.05) 0.50 (0.02) pin width Panel cut-out: 28.4 x 11.4 (1.12 x 0.45) a 11.0 (0.43) 14.0 (0.55) 28.0 (1.10) 2.00 (0.08) pin pitch 5.00 (0.20) a. b. c. d. Panel thickness: 1.0 - 2.5 (0.04 - 0.10) 2.00 6.00 1.60 6.00 (0.08) (0.24) (0.06) (0.24) PANEL FITTING Panel Module 1 2 FUNCTIONAL BLOCK DIAGRAM PIN CONFIGURATION (rear view) BL- V+ Vref CAL CAL INLO XDP DP3 DP2 10 DP1 INHI INLO V- LCOM BL- INHI V+ 1 GND LXDP A/D + _ 1 V- GND 8 DP3 2 1 XDP www.lascarelectronics.com Page 2 of 4 Page 2 of 4 DPM 1AS-BL 31/2 Digit Backlit LCD Voltmeter Module CIRCUIT DIAGRAM PIN FUNCTIONS 1. 2. 3. 4. V+ GND VBL- Positive power supply to the meter. 0V power supply to the meter (3.0 to 7.5V meter power supply applications only). Negative power supply to the meter (6.0 to 15.0V meter power supply applications only). Connect to the meter's negative supply voltage to switch on the LED backlighting. For meter supply voltages above 5V, add a series resistor Rs. See Applications for suitable circuit diagrams. 5. INHI Positive measuring input. 6. INLO Negative measuring input. 7. DP1 Connect to XDP to display DP1 (199.9). 8. DP2 Connect to XDP to display DP2 (19.99). 9. DP3 Connect to XDP to display DP3 (1.999). 10. XDP Connect to pin 7, 8 or 9 to display required decimal point. Note: A negative supply is generated internally and mirrors the positive supply. For example: if V+ is +5V, then the internally generated V- is -5V. When measuring with the input referenced to the same supply rail as that of the panel meter, then the limitations on the input range are (V- + 1.5V) to (V+ - 1.5V). Solder Links: LCOM Normally Open. Connects INLO to COM. LXDP Normally Closed. Cut this link to disable the internal decimal point drive circuit and thereby reduce the meter's current consumption. www.lascarelectronics.com Page 3 of 4 DPM 1AS-BL 31/2 Digit Backlit LCD Voltmeter Module SCALING Two external 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 re-calibrated by adjusting the calibration potentiometer on the rear of the module. FSR 2V 20V 200V 2000V* 200A 2mA 20mA 200mA Voltage (Vin) Current (Iin) Ra 910k 1M 1M 1M 0R 0R 0R 0R Rb 100k 10k 1k 100R 1k 100R 10R 1R Ra + INHI Vin or Iin Rb DPM 1AS-BL - 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. 5V supply operation (3.0 to 7.5V Meter Power Supply) +3.0 to +7.5V +3.0 to +7.5V 1 V+ + 5 DP1 8 DP2 9 DP3 200mV - 6 XDP INLO 5 + BL6 - 4 6 I- INLO if V+>5V then Rs=(V+ - 5V) 0.015 GND Measuring a single ended input voltage referenced to supply, i.e. the input voltage and the meter's power supply share the same 0V rail. Ensure solder link LCOM is open. INHI Rb INLO 2 0V 5 I+ 200mV 10 V+ INHI GND 2 1 V+ No DP 7 INHI +3.0 to +7.5V 1 GND 2 0V 0V Measuring a current from a circuit which is floating with respect to the DPM's supply, i.e. the current and the meter's power supply are isolated from each other. Ensure solder link LCOM is closed. 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. Ensure solder link LCOM is closed. 9V supply operation (6.0 to 15.0V Meter Power Supply) +3.0 to +7.5V +6.0 to +15.0V 1 V+ + 5 - V+ BL6 4 V3 Measuring a single ended input voltage referenced to supply, i.e. the input voltage and the meter's power supply share the same 0V rail. Ensure solder link LCOM is open. 4 Rs=(V+ - 5V) 0.015 V3 DPM 1AS-BL 6 I- Issue 3 3 0V Measuring a current from a circuit which is floating with respect to the DPM's supply, i.e. the current and the meter's power supply are isolated from each other. Ensure solder link LCOM is closed. February/2002 www.lascarelectronics.com INLO V- 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. Ensure solder link LCOM is closed. Specifications liable to change without prior warning INHI Rb INLO Rs=(V+) - (V-) - 5V 0.015 5 I+ BL- 6 1 V+ INHI 200mV INLO -3.0 to -7.5V 5 + INHI 200mV +6.0 to +15.0V 1 M.C. Applies to DPM 1AS-BL/2 Page 4 of 4 Page 4 of 4