EV-131 AAT4295 EVAL: Single RGB Controller Introduction The AAT4295 EVAL board demonstrates the operation of the AAT4295 SmartSwitch™. This device has three low side N-channel load switches which are serially controlled. The AAT4295 operates from 1.8V to 5.5V, making it ideal for use in 2.5V, 3.3V, or 5V systems as well as systems powered by lithium-ion/polymer batteries. For demonstration purposes, an AAT3110 voltage doubling charge pump has been incorporated to provide a regulated voltage source to power the system load, which is an RGB LED. The AAT4295 is controlled by an S2Cwire™ (Simple Serial Control™) interface with easy control and efficiency. The device is enabled with the desired switch configuration after a short set of data pulses is sent to the EN/SET input and holding the line pulled to a logic high. In the enabled state, the AAT4295 typically consumes less than 3µA of quiescent current. When EN/SET is pulled to a logic low, the device is disabled and each output switch is placed in a high impedance open state. The switch resistance of the low side N-channel MOSFET switches is approximately 2Ω. This document describes the evaluation board and its accompanying user interface. In addition, a brief “Getting Started” section is included to help the user begin operating the evaluation board. A schematic of the complete circuit and the actual board layout are also included in the documentation. For additional information, please consult the AAT4295 product datasheet. Schematic VCC R9 1K 02 1 4 3 5 02 1 4 3 5 02 1 4 3 5 02 1 4 3 5 02 1 4 3 5 R10 1K R11 R12 R13 1K 1K 1K 1 2 3 4 SW1 SW2 C1 1µF U3 VDD GP5 GP4 GP3 VSS GP0 GP1 GP2 8 7 6 5 PIC12F675 SW3 Off SW4 3 SW5 On 2 2.7V - 5V DC+ DC- 1 J1 U1 1 2 3 4 C3 10µF VOUT C+ GND VIN GND CGND SHDN C2 1µF 8 7 6 5 U2 VCC R7 100K 1 2 3 4 VIN OUT3 N/C OUT2 N/C OUT1 EN GND 8 7 6 5 G D2 R3 70 B D6 R D1 R2 68 C4 10µF 100K R8 AAT3110 B RGB 1 D3 VCC R1 130 G D5 R6 70 R D4 R5 68 RGB 2 R4 130 AAT4295 Figure 1: Evaluation Board Schematic. EV-131.2007.01.1.0 1 EV-131 AAT4295 EVAL: Single RGB Controller Getting Started An external power supply is required; connect the positive terminal to DC+ and the negative terminal to DC-. The power supply voltage level can be set anywhere between 1.8V and 5.5V. To simulate operation from an LiIon battery source, set the power supply to 3.6V. After applying power to the board, ensure that the jumper J1 is in the ON position. There are five momentary push button switches on the board, labeled SW1 through SW5. After a switch or combination of switches are pressed and released, the on-board microcontroller will send the corresponding S2Cwire programming data to the AAT4295's EN/SET pin. The AAT4295 output settings table can be found in the product datasheet (Table 1, page 9). Two common Anode type RGB are used for system load. The AAT4295’s low-side switches connect each red, green and blue LED to ground with a series ballast resistor to control the forward current through the LED. The circuit is typically used for fashion lighting applications in portable products such as mobile phone handsets. By pressing SW1, all outputs should be turned on. All outputs are reset and RGBs should turn off by pressing SW5 once. Holding switches SW1 and SW5 together for longer than 1.5 seconds activates the auto cycling mode through the microcontroller. The microcontroller will submit a burst of edges, pause, and submit another burst of edges and so on. It starts by submitting 8 edges, then submitting 7 edges, and so on, submitting 1 edge at the end. The two RGB LEDs should blink three times before the sequence of auto-cycling. Other detailed operations are described in Table 1. User Interface Functionality Switch(es) Pushed SW1 SW2 SW3 SW4 SW5 SW1 + SW5 Description [Push/Release once] Turn on all. (RGB becomes White LED) [Push/Release once] Toggle On/Off of S1 (red LED). [Push/Release once] Toggle On/Off of S2 (green LED). [Push/Release once] Toggle On/Off of S3 (blue LED). [Push/Release once] Reset: Turn off all. [Push/Release together] Auto Cycling. Blinks (On/Off) for three times and goes into Binary-decrement mode for 3 times. Table 1: User Interface Functionality 2 EV-131.2007.01.1.0 EV-131 AAT4295 EVAL: Single RGB Controller Printed Circuit Board Figure 2: AAT4295 Evaluation Board Top Layer (not to scale). Figure 3: AAT4295 Evaluation Board Bottom Layer (not to scale). EV-131.2007.01.1.0 3 EV-131 AAT4295 EVAL: Single RGB Controller AAT4295 EVAL Component Listing Component U1 U2 U3 SW1 - SW5 R1, R4 R2, R5 R3, R6 R7 R8 R9 - R12 C3, C4 C2 C1 RGB1, RGB2 J1 Part Number Description Manufacturer AAT4295IJS AAT3110IJS PIC12F675 Single RGB Controller; SC70JW-8 Package Regulated Charge Pump, SC70JW-8 Package 8-bit CMOS, FLASH-based µC; 8-pin PDIP Package Switch Tact, SPST, 5mm 130Ω, 1%, 1/4W; 0805 68Ω, 1%, 1/4W; 0805 70Ω, 1%, 1/4W; 0805 100KΩ, 5%, 1/4W; 0402 100KΩ, 5%, 1/4W; 0805 1KΩ, 5%, 1/4W; 1206 10µF, 10V, X5R, 10%, 1206 1µF, 6.3V, X7R, 10%, 0603 1µF, 10V, X7R, 10%, 1206 Common Anode RGB Conn. Header, 2mm zip AnalogicTech AnalogicTech Microchip PTS645TL50 Chip Resistor Chip Resistor Chip Resistor Chip Resistor Chip Resistor Chip Resistor GRM319R61A106KE19 GRM185R60J105KE21 GRM319R71A105KA01 1615 SMD LED Series PRPN401PAEN ITT Industries Vishay Vishay Vishay Vishay Vishay Vishay Murata Murata Murata Lasemtech Sullins Electronics Table 2: AAT4295 Evaluation Board Component Listing. © 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. Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’s standard warranty. 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. Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737- 4600 Fax (408) 737- 4611 4 EV-131.2007.01.1.0