General Digital-designed Dual LED Driver PCB POWER INPUT Input on power connector is specified to accept 9 16 Vdc, nominal 12 Vdc.

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1 Dual LED Driver for LCDs OVERVIEW LED BACKLIGHT CONTROLLER FAMILY General Digital s Dual LED Driver PCB is a dual channel, boost-mode LED driver intended to drive Daylight and NVIS combo rails, or two simultaneous Daylight rails. LED OUTPUTS Each of the two channels is capable of driving up to 8 strings of LEDs, at up to 45 V and 00 ma per string. The two channels can be enabled separately for two-mode operation or synchronized for single-mode operation. General Digital-designed Dual LED Driver PCB POWER INPUT Input on power connector is specified to accept 9 6 Vdc, nominal 2 Vdc. IN-FIELD FIRMWARE PROGRAMMING The Dual LED Driver PCB is capable of being upgraded via a UART connection. All behavioral aspects of the controller board can be modified via a firmware update. THERMAL OVERLOAD PROTECTION The Dual LED Driver PCB includes one temperature sensor input designed for a Microchip MCP9700A thermal sensor. Thermal sensors should be located as close to the center of the LED rail as possible. The microcontroller will apply a cutback percentage to the dimming PWM signal to reduce temperature in overtemp conditions. Note the typical cutback on the Overtemp Output Correction graph (Figure 2). Overtemp parameters are configured in firmware and will vary based on LCD temperature specs. Leave this sensor unconnected to disable thermal protection. Document No v.0 Page of 7

2 General Digital s Dual LED Driver Board has many features that offer significant improvements and benefits over standard backlight controllers. FEATURES Ideal for industrial/military requirements BENEFITS Ideal for extended operating temperature environments Extended operating temperature Up to 3000: dimming ratio 9 6 VDC input Small form factor We source components of superior quality and performance Embedded microcontroller FEATURES & BENEFITS Dual LED drivers - Independent LED string regulation Spread Spectrum frequency modulation Open and short circuit protection Configuration control Long product life cycle Designed and manufactured in the U.S.A. Support for a wide range of LCDs Embedded Microcontroller/Programmable Performance Temperature sensors and intelligent over-temperature algorithm Set maximum brightness limits for both backlight modes (High Bright and NVIS) Current settings can be independently controlled for each channel Analog or PWM dimming Traceability; repeatability; sustainability; minimal need for costly recertification Sustainability, LTB and EOL announcements; replace obsolete components with like or equivalent to extend life cycle Customer confidence working with an established company that has experience serving the industrial and military markets (40+ years) Flexibility and compatibility Execute Complex Command and Control Achieve maximum brightness under varying thermal conditions while protecting expensive electronics from critical failure Optimize brightness performance, power consumption and heat generation; ensure LCD always visible Day and NVIS rails can be calibrated independently Flexible dimming options Customize Performance Save and restore last backlight mode on power-up Default backlight mode Overtemp backlight override Programming port Execute Complex Command and Control Power-up in desired backlight mode (e.g., NVIS Mode to prevent blinding operatives or giving up position) Provide maximum brightness when critically needed regardless of temperature Upgrade firmware in the field to minimize expense of downtime, shipping and insurance Document No v.0 Page 2 of 7

3 GENERAL Parameter Minimum Maximum Operating Temperature C LED String Current Matching % Dimming Ratio N/A 3000: N/A Dimming Frequency Hz Efficiency Typical Conditions: +2 Vdc IN, +25 C 87% 90% Connector J3 Power Pin Signal Notes Molex/ Mate (Molex/ ) Vin Power Input V 5 6 GND Power Return GND GND GND GND V Connector J6: Discrete Controls Hirose DF3A-5P-.25H(5) [Mate: Hirose DF3-5S-.25C] Pin Signal Notes 3V3 +3.3V Output, Brightness Pot V High Active, Weak Pull-Up V 2 Enable Enable Input Low 0.7 V Enable Input High 2.6 V Analog or PWM Dimming Signal V Analog Dimming Range SW2. On 0 5 V 3 DIM Analog Dimming Range SW2. Off V PWM Input Low 0.7 V PWM Input High 2.6 V PWM Dimming Frequency Hz Low Active NVG Enable, Weak Pull-Up V 4 NVG_En NVG Mode Input Low 0.7 V Enable Input High 2.6 V 5 GND Electrical Ground GND GND GND GND V Document No v.0 Page 3 of 7

4 Connector J - DAY LED Driver Pin Signal Notes (refer to Figure below) Molex/ (Mate: Molex/502-00) DAY_CA Day Common Anode V 2 DAY_CA Day Common Anode V 3 DAY_CA Day Common Anode V 4 DAY_C Day Cathode 00 ma 5 DAY_C2 Day Cathode 2 00 ma 6 DAY_C3 Day Cathode 3 00 ma 7 DAY_C4 Day Cathode 4 00 ma 8 DAY_C5 Day Cathode 5 00 ma 9 DAY_C6 Day Cathode 6 00 ma 0 DAY_C7 Day Cathode 7 00 ma DAY_C8 Day Cathode 8 00 ma Connector J2 - NVG LED Driver Molex/ (Mate: Molex/ ) Pin Signal Notes (refer to Figure below) NVG_CA NVG Common Anode V 2 NVG_CA NVG Common Anode V 3 NVG_C NVG Cathode 50 ma 4 NVG_C2 NVG Cathode 2 50 ma 5 NVG_C3 NVG Cathode 3 50 ma 6 NVG_C4 NVG Cathode 4 50 ma 7 NVG_C5 NVG Cathode 5 50 ma 8 NVG_C6 NVG Cathode 6 50 ma 9 NVG_C7 NVG Cathode 7 50 ma 0 NVG_C8 NVG Cathode 8 50 ma Document No v.0 Page 4 of 7

5 Connector J4 Temperature Sensor Pin Signal Notes Molex/ (Mate: Molex/ ) 3V3 +3.3V output for MCP9700A sensor V 2 DAY_TEMP Analog Temperature Sensor Input V MCP9700A Temperature Sense Range C 3 GND Power Return for MCP9700A Sensor GND GND GND GND V Figure Figure 2 Document No v.0 Page 5 of 7

6 Switch SW SW. SW.2 SW.3 SW.4 SW.5 SW.6 SW.7 SW.8 Description Value ON ON ON ON X X X X Day Cathode Current 00 ma OFF ON ON ON X X X X Day Cathode Current 95 ma ON OFF ON ON X X X X Day Cathode Current 90 ma OFF OFF ON ON X X X X Day Cathode Current 85 ma ON ON OFF ON X X X X Day Cathode Current 80 ma OFF ON OFF ON X X X X Day Cathode Current 75 ma ON OFF OFF ON X X X X Day Cathode Current 70 ma OFF OFF OFF ON X X X X Day Cathode Current 65 ma ON ON ON OFF X X X X Day Cathode Current 60 ma OFF ON ON OFF X X X X Day Cathode Current 55 ma ON OFF ON OFF X X X X Day Cathode Current 50 ma OFF OFF ON OFF X X X X Day Cathode Current 45 ma ON ON OFF OFF X X X X Day Cathode Current 40 ma OFF ON OFF OFF X X X X Day Cathode Current 35 ma ON OFF OFF OFF X X X X Day Cathode Current 30 ma OFF OFF OFF OFF X X X X Day Cathode Current 25 ma X X X X ON ON ON ON NVG Cathode Current 50 ma X X X X OFF ON ON ON NVG Cathode Current 47.5 ma X X X X ON OFF ON ON NVG Cathode Current 45 ma X X X X OFF OFF ON ON NVG Cathode Current 42.5 ma X X X X ON ON OFF ON NVG Cathode Current 40 ma X X X X OFF ON OFF ON NVG Cathode Current 37.5 ma X X X X ON OFF OFF ON NVG Cathode Current 35 ma X X X X OFF OFF OFF ON NVG Cathode Current 32.5 ma X X X X ON ON ON OFF NVG Cathode Current 30 ma X X X X OFF ON ON OFF NVG Cathode Current 27.5 ma X X X X ON OFF ON OFF NVG Cathode Current 25 ma X X X X OFF OFF ON OFF NVG Cathode Current 22.5 ma X X X X ON ON OFF OFF NVG Cathode Current 20 ma X X X X OFF ON OFF OFF NVG Cathode Current 7.5 ma X X X X ON OFF OFF OFF NVG Cathode Current 5 ma X X X X OFF OFF OFF OFF NVG Cathode Current 2.5 ma Switch SW2 SW2.7 SW2.8 Description Value ON ON Reserved Reserved OFF ON Reserved Reserved ON OFF Dim Select PWM OFF OFF Dim Select Analog Document No v.0 Page 6 of 7

7 MECHANICAL / FOR YOUR INFORMATION J.600 J2 Ø0.25 (X4) Figure 3 Note: J5 and J7 are factory configured REVISION HISTORY Rev. No. ECN No. Date Description Initial April 3 Created document JG E October 4 PCB updated, requiring many detail changes JG J3 J4 J5 J6 J SW SW2 ON CTS ON CTS DISCLAIMER Information contained in this document is proprietary to General Digital Corporation and is current as of publication date. This document may not be modified in any way without the express written consent of General Digital. Product processing does not necessarily include testing of all paramters. General Digital reserves the right to change the configuration and performance of the product and to discontinue product at any time. CONNECT GENERAL DIGITAL CORPORATION 8 Nutmeg Road South South Windsor, Connecticut Document No v.0 Page 7 of 7