3 2 L E D D R I V E R S : ICs LED7707 Monolithic DC/DC Converter for LED Driving The new LED7707 is a monolithic DC/DC converter for LED driving specifically designed for LCD backlighting and general lighting. It consists of a highly-efficient boost converter integrating a power MOSFET and six controlled-current generators (ROWs). The device can manage an output voltage up to 36V (example is 10 white LEDs x row). The boost section is based on a constant switching frequency, peak current-mode architecture. The boost output voltage is controlled so that the lowest voltage of the ROW, referred to SGND, is equal to an internal reference voltage (700 mV typical). The input voltage range is from 4.5V up to 36V. In addition, the LED7707 has an internal 5V LDO regulator that supplies the internal circuitry of the device and is capable of delivering up to 40 mA. The input of the LDO is the main input voltage (VBATT). The boost section switching frequency can be externally adjusted from 200 kHz to 1 MHz. It also has an internal fixed value of 660 kHz (typical), which eliminates the need for a resistor, an important feature in minimum component-count applications. The frequency pin (FSW) can also be used as the synchronization input, allowing the LED7707 to operate both as the master or the slave. The generators can be externally programmed to sink from 16 mA up to 85 mA and can be dimmed via a PWM signal (1 percent dimming duty-cycle at 1 kHz can be managed). For highcurrent LEDs, it is possible to parallel the outputs to get the maximum output current value of 510 mA (6 ROWs x 85 mA). The device is able to detect and manage open- and shorted-LED faults. If some ROWs are not used, during the start up, the device is able to self-detect and automatically disconnect the ROWs without any fault detection. Output over-voltage, internal power MOSFET over-current, and thermal shutdown are provided as protection. LED7707 demo board Features Benefits Applications * Constant-frequency, peak, current control mode * High efficiency thanks to adaptive-output voltage * Backlighting in LCD panels for battery/AC adapter supplied equipment such as: * Internal power MOSFET * High-performance 36V rated current generators * External sync for multi-device applications * Pulse-skip power saving mode at light load * 1% dimming duty-cycle at 1 KHz can be managed * Programmable soft-start and over voltage protection - GPS navigator backlighting - LCD monitor backlighting * General lighting * Keeps externals tiny * Ceramic output capacitor * Demo board and application notes available * Six ROWs with 85 mA maximum current capability (adjustable) * Parallelable rows up to 510 mA (6 ROWs x 85 mA) * Up to 36V output voltage (example 10 white LED per row) * 2% current matching between ROWs * LED failure (open- and short-circuit) detection * Housed in VQFPN-24L space-saving package Product Specifications Part Number Type Dimming Type Number of LEDs/ String Number of Strings Configuration Input Voltage (VDC) LED7707 Boost converter PWM 36V (example 10 white LEDs) 6 Series/parallel 4.5-36 MARKETS L EGEND Output Voltage (VDC) Output Current (mA) Adaptive to 36V 6 ROWs x 85 COMMERCIAL LIGHTING FLASHLIGHTS Peak Efficiency (%) Diagnostic Capabilities Interface >90 Short/open -- TRANSPORTATION BACKLIGHTING Markets SIGNAGE LED7707 application schematic Arrow Electronics Lighting Group 1.888.9LIGHT1 http://lighting.arrow.com L E D D R I V E R S : ICs 3 3 24-Bit Constant-Current LED Sink Driver with Output Error Detection The STP24DP05 is a monolithic, low-voltage, low current-power 24-bit shift register designed for LED panel displays. The 24-bit are grouped into three sets of 8-bit for RGB control to simplify PCB layout in parallel to achieve high resolution video display. In the output stage, 24 regulated current sources were designed to provide 5 mA to 80 mA constant current to drive the LEDs. The 8 x 3 shift registers data flow sequence order can be managed with two dedicated pins. The STP24DP05 has a dedicated pin to activate the outputs with a sequential delay that will prevent in-rush current during outputs turn-on. The device detection circuit checks three different conditions that can occur on the output line: short-to-GND, short-to-VO, or open line. The data detection results are loaded in the shift registers and shifted out via the serial line output. The detection functionality is activated with a dedicated pin, or as an alternative, through a logic sequence that allows the user to enter or exit from detection mode. Through three external resistors, users can adjust the output current for each 8-channel group, controlling the light intensity of LEDs. STP24DP05 evaluation board Features Benefits Applications * 20V output driving capability * Superior display quality * Full-motion RGB video wall display * 25 MHz clock frequency * Finer brightness control through three independent external resistors * Monochrome LED signs * 3.3V and 5V supply voltage range * Up to 80 mA drive capability per channel * Thermal shutdown * Accurate color balance and white points * Remote diagnostics * Thermal error flag * Billboards and scoreboards * Large-panel LCD backlighting units * Traffic display * Gaming machine * Channel letter signs * Gradual outputs delay * Short- and open-LED detection * Controlled in-rush current * TQFP-48 exposed pad, high thermal efficiency package Product Specifications Part Number STP24DP05 Type Dimming Type Number of LEDs/ String Linear SW/PWM signaling 20V (example 6 green LEDs) MARKETS LEG END Input Output Output Peak Number of Configuration Voltage Voltage Current Efficiency Strings (VDC) (VDC) (mA) (%) 24 Series/parallel 3.3-5 20 80 COMMERCIAL LIGHTING -- Diagnostic Capabilities Open/short LED detection FLASHLIGHTS TRANSPORTATION Interface Markets SPI BACKLIGHTING SIGNAGE STP24DP05 typical application circuit Arrow Electronics Lighting Group 1.888.9LIGHT1 http://lighting.arrow.com 3 4 L E D D R I V E R S : ICs 4-Bit Constant-Current Power-LED Sink Driver STMicroelectronics has introduced the STP04CM05, a monolithic 4-bit shift register designed to supply high-power RGGB LEDs achieving high precision color control. Each channel provides a controlled current ranging from 80 mA to 400 mA. The device has 1 percent precision among the channels and 6 percent chip-to-chip. The STP04CM05 guarantee 20V output driving capability, allowing users to connect more LEDs in series. The high clock frequency, 30 MHz, makes the device suitable for high data transmission. The 3.3V voltage supply is useful in applications that interface with 3.3V microcontroller. STP04CM05 evaluation board Features Benefits Applications * 20V output driving capability * Architectural lighting * 30 MHz clock frequency * Constant voltage and constant current * 3.3V and 5V supply voltage range * Adjustable current limit * Ambient lights * Controlled in-rush current * Simple to implement * Automotive interior lighting * Thermal shutdown * Over-voltage protection * Light indicator for white goods * Available in SO, TSSOP, and TSSOP exposed pad * High efficiency * Special illumination * Adjustable output current through one external resistor Product Specifications Part Number Type STP04CM05 Linear Dimming Type Number Input Voltage of Strings Configuration (VDC) Number of LEDs/String SW/PWM signaling 20V (example 5 green LEDs) MARKETS LEG END 4 Series/parallel 3.3-5.5 Output Voltage (VDC) 20 COMMERCIAL LIGHTING Output Current (mA) Peak Efficiency (%) Diagnostic Capabilities* Interface 400 -- TSD SPI FLASHLIGHTS TRANSPORTATION BACKLIGHTING Markets SIGNAGE *Diagnostic capabilities: TSD: Thermal shutdown STP04CM05 typical application diagram Arrow Electronics Lighting Group 1.888.9LIGHT1 http://lighting.arrow.com L E D D R I V E R S : ICs 3 5 15W TRIAC Dimmable LED Driver Based on L6562A The L6562A is the latest proposal for power factor correction. The application note AN2711 presents a 15W driver for LEDs, based on single stage fly-back PFC, that is compatible with TRIAC phasecontrol dimmers. The design gives luminaire manufacturers a low-cost, commonly available dimming option for home fixtures. An additional benefit is that when not wired to a dimmer, the unit's power factor is over 0.9. This solution is scalable up to 60W. Features Benefits Applications * High efficiency >87% * Solution compatible with common TRIAC dimmers * Downlight * No large electrolytic capacitor * Able to meet FCC class B * Small form factor * Chandelier * High power factor >0.9 * Scalable up to 60W * Dimmable ballast replacement STEVAL-ILL016V1 evaluation board Product Specifications Part Number Type Dimming Type STEVAL-ILL016V1 Evaluation board TRIAC dimmable Number of LEDs/ String Number of Strings Configuration Input Voltage (VDC) 8 (1W) 2 Series/parallel 120 VAC Output Voltage (VDC) Output Current (mA) Peak Efficiency (%) Diagnostic Capabilities 36V 350 87 -- COMMERCIAL LIGHTING MARKETS LEGEND FLASHLIGHTS TRANSPORTATION Interface Markets -- BACKLIGHTING SIGNAGE ST LED Evaluation Boards ST Board Order Code LED Board Description STEVAL-ILL001V1 Dimmable driver for HB power LEDs with Viper22A (DALI connector) STEVAL-ILL002V3 HB-LED with diagnostic (40 LED) based on STP08DP05 STEVAL-ILL002V4 HB-LED with diagnostic (40 LED) based on STP08DP05 STEVAL-ILL003V1 HB-LED without diagnostic (32 LED) based on STP16CP596 STEVAL-ILL003V2 HB-LED without diagnostic (32 LED) based on STP16CP05 STEVAL-ILL005V1 VIPer12A offline, constant-current driver for high-intensity LEDs STEVAL-ILL006V1 VIPer22A offline, constant-current driver for high-intensity LEDs STEVAL-ILL007V1 High intensity LED driver for MR-16 format based on L5973D STEVAL-ILL008V1 LED flashlight demo STEVAL-ILL009V3 OSTAR projection module STEVAL-ILL009V4 OSRAM DRAGON LEDs module STEVAL-ILL009V5 New RGB color control board based on STP04CM05 and ST1S10 STEVAL-ILL010V1 High-intensity LED dimming driver based on L6902 STEVAL-ILL014V1 Constant-current controller for high brightness LEDs based on STCS1 STEVAL-ILL015V1 HB-LED driver with diagnostic based on STP24DP05 and STM32 STEVAL-ILL016V1 15W offline TRIAC dimmable LED driver based on L6562AD and TSM1052 (USA Market-115V) STEVAL-ILL018V1 OSRAM Golden DRAGON white LED module (LUW W5AM) STEVAL-ILL018V2 OSRAM Golden DRAGON warm white LED module (LCW W5AM) STEVAL-ILL018V3 OSRAM Golden DRAGON amber (red) LED module (LA W55M) STEVAL-ILL018V4 OSRAM Golden DRAGON blue LED module (LB W55M) STEVAL-TLL001V1 White LED controller based on STLD40D STEVAL-TLL002V1 Flash driver based on STCF01 STEVAL-TLL003V1 Power Flash driver based on STCF02 STEVAL-TLL004V1 Power Flash driver based on STCF03 STEVAL-TLL005V1 Power Flash evaluation board based on STCF03 and ST7 MCU (include the STEVAL-TLL004V1) Arrow Electronics Lighting Group 1.888.9LIGHT1 http://lighting.arrow.com Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: STMicroelectronics: STEVAL-ILL018V4