OVERVIEW LED BACKLIGHT CONTROLLER FAMILY

Transcription

1 Dual Mini LED Driver for LCDs OVERVIEW LED BACKLIGHT CONTROLLER FAMILY General Digital s Dual Mini 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 4 strings of LEDs, at up to 36 V and 100 ma per string. The two channels can be enabled separately for two-mode operation or synchronized for single-mode operation. General Digital-designed Dual Mini LED Driver PCB POWER INPUT Power input on connector J2 is specified to accept 9 16 VDC, nominal 12 VDC. IN-FIELD FIRMWARE PROGRAMMING The Dual Mini is capable of being upgraded via a UART connection on connector J5. All behavioral aspects of the Dual Mini can be modified via a firmware update. THERMAL OVERLOAD PROTECTION The Dual Mini includes two temperature sensor inputs 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. Typical cutback can be seen in Figure 2 on page 4. Overtemp parameters are configured in firmware and will vary based on LCD temperature specs. Leave this sensor unconnected to disable thermal protection. Document No v0.0 Page 1 of 7

2 General Digital s Dual Mini LED Driver Board has many features and benefits that outperform standard backlight controllers. FEATURES Ideal for industrial / military requirements BENEFITS Ideal for extended operating temperature environments Extended operating temperature Up to 3000:1 dimming ratio 9 16 VDC input Small form factor We source components of superior quality and performance Embedded microcontroller Dual LED drivers - Independent LED string regulation Spread Spectrum frequency modulation FEATURES & BENEFITS 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 minimum and maximum brightness limits for both backlight modes (High Bright and NVIS) Set minimum and maximum frequency limits for both backlight modes (High Bright and NVIS) Current settings can be independently controlled for each channel Programmable dimming algorithms 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 Adjust dimming frequency to avoidaudible noise or wide dimming ratio Day and NVIS rails can be calibrated independently Standard (linear) or custom (e.g., logarithmic) profiles; increase fidelity in spectrum where needed or tune to sensitivity of the human eye 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 v0.0 Page 2 of 7

3 PART NUMBER GENERAL Parameter Minimum Maximum Operating Temperature C LED String Current Matching % Dimming Ratio 5000:1 Dimming Frequency Hz Efficiency Vin=9 V Vin=12 V Vin=16 V Standby Current (EN=0 V) Vin=9 V Vin=12 V Vin=16 V % % % ma ma ma Figure 1 Connector J1 LED Connection A Molex/ (Mate: Molex/ ) (refer to Figure 1 above) 1 DAY_CA Day Channel Common Anode V 2 DAY_C1 Day Channel Cathode 1 3 DAY_C2 Day Channel Cathode 2 4 NVG_CA NVG Channel Common Anode V 5 NVG_C1 NVG Channel Cathode 1 6 NVG_C2 NVG Channel Cathode 2 Connector J3 LED Connection B Molex/ (Mate: Molex/ ) (refer to Figure 1 above) 1 DAY_CA Day Channel Common Anode V 2 DAY_C3 Day Channel Cathode 3 3 DAY_C4 Day Channel Cathode 4 4 NVG_CA NVG Channel Common Anode V 5 NVG_C3 NVG Channel Cathode 3 6 NVG_C4 NVG Channel Cathode 4 Document No v0.0 Page 3 of 7

4 Connector J2 Power and Control Molex/ (Mate: Molex/ ) Vin Power Input V Power Return High Active Enable, Weak Pull-up V V 9 EN Enable Input Low 0.7 V Enable Input High 2.6 V Analog or PWM Dimming signal V Analog Dimming Range SW6 ON 0 5 V 10 DIM Analog Dimming Range SW6 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 11 NVG_EN NVG Mode Input Low 0.7 V Enable Input High 2.6 V Connector J4 Day/Top Temperature Sensor Molex/ (Mate: Molex/ ) 1 3V3 +3.3V output for MCP9700A sensor V 2 DAY_TEMP Analog Temperature Sensor Input V MCP9700A Temperature Sense Range C 3 Power Return for MCP9700A Sensor V Figure 2 Document No v0.0 Page 4 of 7

5 Connector J5 Serial Interface Molex/ (Mate: Molex/ ) 1 5V0 +5.0V Input for Bootloading V I²C Clock V 2 SCL SCL Input Low 1.0 V SCL Input High 2.3 V I²C Data V 3 SDA SDA Input Low 1.0 V SDA Input High 2.3 V Bootloader TX Output V 4 BOOT_TX BOOT_TX Input Low 0.7 V BOOT_TX Input High 2.6 V 5 RESET MCU Reset, Weak Pull-up V Bootloader RX Input V 6 BOOT_RX BOOT_RX Input Low 0.7 V BOOT_RX Input High 2.6 V 7 Power Return for Bootloading V 8 Ground for Shield Drain Connection V Connector J6 NVG/Bottom Temperature Sensor Hirose/DF13C-3P-1.25V(50) (Mate: Hirose/ DF13-3S-1.25C) 1 3V3 +3.3V Output for MCP9700A Sensor V 2 NVG_TEMP Analog Temperature Sensor Input V MCP9700A Temperature Sense Range C 3 Power Return for MCP9700A Sensor V Document No v0.0 Page 5 of 7

6 Switch SW1 SW1.1 SW1.2 SW1.3 SW1.4 SW1.5 SW1.6 SW1.7 SW1.8 Description Value ON ON ON ON X X X X Day Cathode Current 100 ma ON ON ON OFF X X X X Day Cathode Current 95 ma ON ON OFF ON X X X X Day Cathode Current 90 ma ON ON OFF OFF X X X X Day Cathode Current 85 ma ON OFF ON ON X X X X Day Cathode Current 80 ma ON OFF ON OFF X X X X Day Cathode Current 75 ma ON OFF OFF ON X X X X Day Cathode Current 70 ma ON OFF OFF OFF X X X X Day Cathode Current 65 ma OFF ON ON ON X X X X Day Cathode Current 60 ma OFF ON ON OFF X X X X Day Cathode Current 55 ma OFF ON OFF ON X X X X Day Cathode Current 50 ma OFF ON OFF OFF X X X X Day Cathode Current 45 ma OFF OFF ON ON X X X X Day Cathode Current 40 ma OFF OFF ON OFF X X X X Day Cathode Current 35 ma OFF OFF OFF ON 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 100 ma X X X X ON ON ON OFF NVG Cathode Current 95 ma X X X X ON ON OFF ON NVG Cathode Current 90 ma X X X X ON ON OFF OFF NVG Cathode Current 85 ma X X X X ON OFF ON ON NVG Cathode Current 80 ma X X X X ON OFF ON OFF NVG Cathode Current 75 ma X X X X ON OFF OFF ON NVG Cathode Current 70 ma X X X X ON OFF OFF OFF NVG Cathode Current 65 ma X X X X OFF ON ON ON NVG Cathode Current 60 ma X X X X OFF ON ON OFF NVG Cathode Current 55 ma X X X X OFF ON OFF ON NVG Cathode Current 50 ma X X X X OFF ON OFF OFF NVG Cathode Current 45 ma X X X X OFF OFF ON ON NVG Cathode Current 40 ma X X X X OFF OFF ON OFF NVG Cathode Current 35 ma X X X X OFF OFF OFF ON NVG Cathode Current 30 ma X X X X OFF OFF OFF OFF NVG Cathode Current 25 ma Switch SW2 SW2.1 SW2.2 Description Value ON ON Dimming Select PWM ON OFF Dimming Select Analog OFF ON Reserved Reserved OFF OFF Reserved Reserved Document No v0.0 Page 6 of 7

7 MECHANICAL / FOR YOUR INFORMATION REVISION HISTORY Figure 3 Rev. No. ECN No. Date Description Initial March 17 Created document JG 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 Scan QR Code to Download Data Sheet Document No v0.0 Page 7 of 7