EV-153 EVALUATION BOARD DATASHEET. AAT2847 EVAL: 4-Channel Backlight Driver with Dual LDOs. Introduction. Getting Started

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1 Introduction EVALUATION BOARD DATASHEET The AAT847 is a highly integrated power solution for single cell Li-Ion/Polymer based liquid crystal display (LCD) display applications. It includes a four channel light emitting diode (LED) backlight driver and two integrated 00mA low dropout voltage regulators (LDOs) as additional power supplies for display and camera related chipsets. The backlight driver in the AAT847 is a low noise tri-mode DC/DC charge pump converter. Each of the four channels of the backlight driver is capable of delivering up to 0mA of bias current for white LEDs. The white LED (WLED) backlight bias current matching is %, which helps provide uniform display brightness. AnalogicTech s AS Cwire (Advanced Simple Serial Control ) serial digital interface is used to enable, disable, and set the current for each backlight LED channel. Each LED channel has sixteen available current level settings in three separate current scales, plus four available current level settings on a low level current scale. Each LED channel is equipped with built-in short circuit protection and auto disable functionality. A low shutdown current feature disconnects the load from the input and reduces quiescent current to less than μa. The AAT847 is available in the thermally enhanced 0-pin x4x0.7mm TQFN package. Getting Started To apply power to the board, connect the supply by shorting the ON prong to the other prongs in the J header. After shorting the ON prong, the red LED7 should illuminate which indicates that power is connected to the AAT847 and microcontroller (MCU). To allow the MCU to interact with the AAT847, connect/short the ON prong to the other prongs in the J4 header. Also to enable LDOA, connect/short the ON prong to the middle prong on the J header. Conversely to enable LDOB, connect/short the ON prong to the middle prong on the J header. The user interface is provided by three buttons. The buttons are DATA, LIGHT, and SW. The modes of operation are detailed in Table. Each button handles a particular function: LIGHT turns on/off the D-D4 LEDs, DATA increments the data register value of the targeted address, SW increments the target address of the AS Cwire interface, and LIGHT+DATA+SW resets the MCU and turns off the AAT847. When the DATA button is pressed and not released, the MCU will incrementally auto-cycle through the available values of the data register for the target address after a short delay. For a detailed device functionality description, regarding address functionality and available data register values, please consult the AAT847 data sheet. Button(s) Pressed/Released LIGHT DATA SW LIGHT+DATA+SW Description Turns on/off D-D4 LEDs Increments [cycles through when not released] data of targeted address (previously pressed/released SW button): see SW Increments the target address [default (address 0)]: Button Press/Release Address Decription st Max Current Scale nd 4 Low Current Scale rd Independent LED Control 4th, repeat 0 D-D4 Current Control Reset. is held logic low Table : User Interface Functionality. EV

2 Schematic J D D D D4 J J R LDOB R R0 C6 R FBB 9 ENA GND 8 7 D FBA LDOA C- C+ D D4 D ENB LDOB IN C+ PGND C- IN OUT U AAT C C R C C LDOA R8 R9 Figure : AAT847 Section Schematic of the Evaluation Board. R6 J4 R7 R R DATA LIGHT R U VDD VSS 8 7 GP GP0 6 GP4 GP 4 GP GP PICF67 C8 R LED7 RED SW Figure : PICF67 Section Schematic of the Evaluation Board. EV

3 Bill of Materials (BOM) Component Part Number Description Manufacturer U AAT847-QI/QG 4-Channel Backlight Driver with Fixed Output Voltage Dual LDOs AnalogicTech U PICF67 Microcontroller Microchip 060ZD0K C-C, C8 C608XRE0K μf, 0V, XR or X7R GRM88R6C0K C608XRA47K 4.7μF, 0V, XR or X7R LMK07BJ47K Taiyo Yuden 060ZDK C, C6 C608XRCK.μF, 0V, XR or X7R GRM88R6AK D-D4 LW M67C White LED Osram LED7 CMD-SRC Red LED; 06 CML Innovative Tech, Inc R-R CRCW06000F kω, %, /0W, 060 Vishay R4 N/A N/A N/A R CRCW0600RF 0Ω, %, /0W, 060 Vishay R6 CRCW F 0Ω, %, /0W, 060 Vishay R7 CRCW06000F 00kΩ, %, /0W, 060 Vishay R8-R Open N/A N/A R-R CRCW06000F 0kΩ, %, /0W, 060 Vishay R4 CRCW060000F 0Ω, %, /4W, 06 Vishay DATA, LIGHT, SW PTS64TL0 Switch Tact, SPST, MM ITT Industries J-J4 PRPN40PAEN Connecting Header, mm Sullins Electronics Table : AAT847-QI/QG Component Listing. Component Part Number Description Manufacturer U AAT847-EE 4-Channel Backlight Driver with Adjustable Output Voltage Dual LDOs AnalogicTech U PICF67 Microcontroller Microchip 060ZD0K C-C, C8 C608XRE0K μf, 0V, XR or X7R GRM88R6C0K C608XRA47K 4.7μF, 0V, XR or X7R LMK07BJ47K Taiyo Yuden 060ZDK C, C6 C608XRCK.μF, 0V, XR or X7R GRM88R6AK D-D4 LW M67C White LED Osram LED7 CMD-SRC Red LED; 06 CML Innovative Tech, Inc R-R CRCW06000F kω, %, /0W, 060 Vishay R4 N/A N/A N/A R CRCW0600RF 0Ω, %, /0W, 060 Vishay R6 CRCW F 0Ω, %, /0W, 060 Vishay R7 CRCW06000F 00kΩ, %, /0W, 060 Vishay R8 CRCW060604F 60.4kΩ, %, /0W, 060 Vishay R9, R CRCW0600F 0kΩ, %, /0W, 060 Vishay R0 CRCW06060F 60kΩ, %, /0W, 060 Vishay R-R CRCW06000F 0kΩ, %, /0W, 060 Vishay R4 CRCW060000F 0Ω, %, /4W, 06 Vishay DATA, LIGHT, SW PTS64TL0 Switch Tact, SPST, MM ITT Industries J-J4 PRPN40PAEN Connecting Header, mm Sullins Electronics Table : AAT847-EE Component Listing. EV

4 Printed Circuit Board Figure : AAT847 Evaluation Board Top Layer (not to scale) 4 EV

5 Figure 4: AAT847 Evaluation Board Bottom Layer (not to scale). Advanced Analogic Technologies, Inc. 0 Scott Boulevard, Santa Clara, CA 904 Phone (408) Fax (408) Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Except as provided in AnalogicTech s terms and conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders. EV