Digit Panel Meters

DMS-30DR Series Daylight Readable, 3½ Digit Panel Meters with Auto-Dimming LED Displays PATENT PENDING FEATURES ■ Super-bright LED displays are readable in direct sunlight! Autodim circuitry automatically adjusts display brightness Includes external brightness adjustment Large (0.56”/14.2mm) easy-to-read red LED display High reliability alternative to LCD displays Ideal for automotive, industrial, and marine applications Encapsulated package mounts in panels or pc-boards Miniature housing: 2.17” x 0.92” x 0.56” (55mm x 23mm x 14mm) 4 differential input ranges provide ±1 count accuracy Single +5V supply; Less than 1-Watt power consumption 0 to +60°C operating temperature range 1 ■ C&D Technologies’ new DMS-30DR Series are the first digital panel meters to offer LED displays that are readable in direct sunlight—no special filters or shading devices are required. Their Autodim circuit automatically adjusts the display’s brightness to suit viewing environments ranging from total darkness to full, brilliant sunlight. A user-accessible brightness adjustment pin enables custom intensity settings or display matching in multiple display applications. Washed out, hard-to-read digital readouts are a thing of the past! Until now, users whose instrumentation required daylight visibility had to settle for less reliable LCD display technology. However, in order to remain legible in low ambient light, LCDs require complex, power-hungry backlighting circuitry. And, these displays typically suffer from very narrow viewing angles. In contrast, DMS-30DR Series LED-based displays’ power consumption drops as ambient light decreases, and their viewing angle extends to nearly 180 degrees vertically and horizontally. All models operate from a single +5V supply, and draw as little as 7mA when operated in total darkness—that’s less than 1/10 Watt. At maximum brightness power consumption is typically less than 200mA (1 Watt). DMS-30DR voltmeters are available in four differential input voltage ranges: ±200mV, ±2V, ±20V and ±200V. Input impedance is 1,000 megohms for the ±200mV and ±2Vwww.DataSheet4U.com inputs and 1 megohm for the ±20V and ±200V inputs. CMRR for all devices is 86dB, and inputs are overvoltage protected to ±250V. Each meter incorporates a precision, ultra-stable voltage reference and is factory calibrated prior to encapsulation. The small size (2.17” x 0.92” x 0.56”) of DMS-30DR meters is achieved by integrating their display, Autodim display drivers, light sensor, reference circuit, and A/D converter into in a rugged epoxy-encapsulated assembly. The device’s 12-pin, component-like, DIP package is both vibration and moisture proof, making them ideal for harsh environments. Each package incorporates a built-in color filter and bezel, and is easily mounted in either panels or pc boards. ■ ■ ■ ■ ■ ■ ■ ■ ■ +5V SUPPLY +5V +5V 12 0.01µF (–) INPUT LO R2 (1) EXTERNAL BRIGHTNESS ADJUSTMENT 2 DC/DC CONVERTER +5V –5V –5V R1 909k 11 (+) INPUT HI 5V RETURN 3 –5V A/D CONVERTER 10 ANALOG COMMON 1.225V REF. 1.82k DP 3 4 0 Vdc DATA 9 +1.225V REFERENCE OUT DP 2 5 LIGHT SENSOR 8 +5V REFERENCE OUT DP 1 6 7 REFERENCE IN (1) R2 is not used on ±200mV (-0) models or ±2V (-1) models. R2 = 100k on ±20V (-2) models and 9.1k on ±200V (-3) models. Figure 1. DMS-30DR Simplified Schematic DIGITAL PANEL METERS MPM_DMS-30DR_A01 Page 1 of 6 www.cd4power.com DMS-30DR Series S U N L I G H T R E A D A B L E , AU T O - D I M M I N G L E D D I S P L AY M E T E R S Performance/Functional Specifications Typical at TA = +25°C and supply voltage = +5V using the single-ended input circuit, unless otherwise noted. Analog Inputs Full Scale Input Range: DMS-30DR-0 DMS-30DR-1 DMS-30DR-2 DMS-30DR-3 Input Impedence: DMS-30DR-0, -1 DMS-30DR-2, -3 Overvoltage Protection ➀ Common Mode Voltage Range CMRR (dc to 60Hz) Control Inputs ➁ Decimal Point Placement (Pins 4-6) Ext. Bright (Pin 2) Performance Sampling Rate Accuracy (3 minute warm-up): DMS-30PC-0 (Vin = +0.19V) DMS-30PC-1 (Vin = +1.9V) DMS-30PC-2 (Vin = +19V) DMS-30PC-3 (Vin = +190V) Zero Reading (Vin = 0 Volts) Temperature Drift (0 = +60°C) +1.225V Reference Output (Pin 9)➁ Power Supply Requirements Supply Voltage Supply Current: Full Sunlight Total Darkness Display Display Type and Size Polarity Indication Overrange Indication Physical/Environmental Operating Temperature Storage Temperature Humidity (non-condensing) Case Material Weight 0 –40 0 – – – +60 +75 95 °C °C % 3½ digit, 0.56"/14.2mm high LED Autopolarity ("–" for negative Vin) "–1_ _ _ " for negative inputs "1_ _ _ " for positive inputs – – +150 3 +250 5 mA mA +4.75 +5.00 +5.25 Volts – – – – “–001” – +1.215 ±1 ±1 ±2 ±2 “000” ±0.2 +1.225 ±3 ±3 ±3 ±3 “001” ±0.4 +1.235 Cnts/°C Volts Counts Counts Counts Counts 2.5 reading per second Tie to pin 3 to activate See Technical Note 1 – – – – – 100 0.9 – – – 1000 1 – – 86 – – ±250 ±2 – MΩ MΩ Volts Volts dB ±200 ±2 ±20 ±200 – – – – mV Volts Volts Volts Min. Typ. Max. Units Ordering Information DMS-30DR- 1 - R - C Input Range: 0 = ±200mV 1 = ±2V 2 = ±20V 3 = ±200V Accessories: DMS-EB-C DMS-EB-RMS-C DMS-PS1-CM-C DMS-30-CP PATENT PENDING RoHS Compliant LED Color: R = Red Multi-purpose (gain/offset, 4-20mA, etc.) For true rms measurements of ac voltages +5V/1.0A AC/DC power supply module Panel cutout punch A panel-mount DMS-BZL2-C is supplied with each unit. TECHNICAL NOTES 1. External Brightness Adjustment (Pin 2): Pin 2 is internally connected to the high impedance input of an operational amplifier that amplifies the output of the DMS-30DR’s ambient light sensor (ALS) circuit. The output of this amplifier varies the voltage that drives the DMS-30DR’s LED display. Leave pin 2 open for standard auto-dimming operation; in this mode, the ALS circuit will automatically adjust the DMS-30DR’s LED brightness to compensate for changes in ambient lighting. As the ambient light striking the ALS increases, the LED display’s brightness will also increase; a decrease in ambient light will reduce the display’s brightness. The ALS circuit’s output signal can be overdriven by applying an externally generated voltage directly to pin 2. External drivers will see approximately 600Kohms referenced to 5V RETURN. With pin 2 at +0.7Vdc or below, the DMS-30DR’s LED display is off, and total current drain from a nominal +5V supply is approximately 1mA. The LED display’s brightness will increase from minimum to maximum as the voltage applied to pin 2 is varied from +0.8V up to +2.5V, respectively. To enable continuous maximum display brightness, connect pin 2 directly to pin 1 (+5V SUPPLY); in this configuration the total current drain for the meter will be approximately 200mA. 2. Minimum-Intensity Adjustment Potentiometer: Users can adjust the DMS-30DR’s minimum LED brightness to suit their requirements by adjusting the ¾-turn, rear-mounted intensity adjustment potentiometer. Please note, this potentiometer will have minimal impact on display brightness in high ambient light environments. See the Mechanical Specifications section for potentiometer locations. The intensity adjustment potentiometer is factory preset to its mid-point position, producing a typical current drain of 7mA. At it’s minimum and maximum positions, current drain is typically 3mA and 13mA, respectively. As viewed from the rear of the meter, with the model number label facing up, turning the potentiometer clockwise increases the display’s intensity. 3. +1.225V REFERENCE OUTPUT (Pin 9): This pin is the output of the meter’s precision +1.225V internal reference IC. Pin 9 is referenced to ANALOG COMMON (pin 10), which in turn sits approximately +2V above pin 3. Pin 9 should be buffered if it’s used to drive external loads since sourcing more than 15µA of current can affect both the Polycarbonate 0.75 ounces (21 grams) ➀ Applies for transient or continuous overvoltages applied to (+) INPUT HI (pin 11) with (–) INPUT LO (pin 12) properly connected. Pin 12 is not overvoltage protected (see Figure 1). Voltages applied to pin 12 should not exceed the supply voltage. ➁ See Technical Notes. DIGITAL PANEL METERS www.cd4power.com MPM_DMS-30DR_A01 Page 2 of 6 DMS-30DR Series S U N L I G H T R E A D A B L E , AU T O - D I M M I N G L E D D I S P L AY M E T E R S accuracy and temperature drift of the meter. A ±1% 1.82K limiting resistor is connected between the reference IC and pin 9. 4. ANALOG COMMON (Pin 10): This pin is connected to an internal, low-noise, “relative” ground. Pin 10 also serves as the internal ground for the +1.225V reference IC. ANALOG COMMON is used in certain differential and “floating” measurements as described in the Applications section of this data sheet, and in DMS Application Note 3. For the vast majority of applications, pin 10 should not be connected to pin 3 (5V RETURN), or to your system’s analog ground. 5. REFERENCE OUTPUT (Pin 8) and INPUT (Pin 7): Pin 8 is a precision reference actively trimmed at the factory. For normal operation, pin 8 must be tied to pin 7 to achieve all listed accuracy and drift specifications. 6. Decimal Point Placement: The location of the decimal point is user selectable, and the decimal point control pins (DP1-DP3) are active low functions. Select the desired decimal point by tying the appropriate pin (pin 4, 5 or 6) to pin 3 (5V RETURN). Unused decimal point location pins should be left open. Hard wiring is preferable, however, you can use logic gates to exercise dynamic control over the location of the decimal point if the following drive conditions are met: Applied “0” Voltage: +0.4V max Drive Current*: 6mA max. * The driving gates must be able to sink this much current (IOL) with a logic “0” output. 7. Gain-Adjust Potentiom