AAT1235IRN-T1 AnalogicTech, AAT1235IRN-T1 Datasheet
AAT1235IRN-T1
Related parts for AAT1235IRN-T1
AAT1235IRN-T1 Summary of contents
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... The high switching frequency (up to 2MHz) provides fast response to load transients and allows the use of small external components. A fully integrated control circuit simplifies the design and reduc- es total solution size. AnalogicTech’s Advanced Simple (AS Cwire™) serial digital input is used to individually ...
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TM SwitchReg Pin Descriptions Pin # Symbol Function 1 VIN Input supply for the converter. Connect a 2.2μF or larger ceramic capacitor from VIN to GND. Boost output over voltage detect pin. Use resistor divider to set the circuit’s external ...
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TM SwitchReg Absolute Maximum Ratings T = 25°C unless otherwise noted. A Symbol Description VIN, IN Input Voltage SW Switching Node EN/SET, Bx, Ax, Maximum Rating RSET, OV, LIN T Storage Temperature Range S T Operating Temperature Range J T ...
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TM SwitchReg Electrical Characteristics V = 3.6V 2.2μF;T = -40°C to +85°C, unless otherwise noted. Typical values are Symbol Description Power Supply V Input Voltage Range IN V Maximum Output Voltage OUT(MAX) V ...
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TM SwitchReg Typical Characteristics Efficiency vs. LED Current (Group B On; Group A Off 4. 1.6 3.9 6.2 8.5 10.8 13.1 Output LED Current (mA) ...
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TM SwitchReg Typical Characteristics LED Current vs. Temperature (All Channels = 20mA) 21 21.0 20.8 20.6 20 20.0 B2 19.8 19.6 19.4 19.2 19.0 -40 - Temperature (° ° C) Shutdown Operation ...
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TM SwitchReg Typical Characteristics Line Transient (All Channels = 20mA) 4.5 4.0 3.5 3.0 Time (50µs/div) Enable Threshold High vs. Supply Voltage and Temperature 1.2 1.1 25°C -40°C 1.0 0.9 +85°C 0.8 0.7 2.7 3.1 3.5 3.9 4.3 4.7 Supply ...
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TM SwitchReg Typical Characteristics EN/SET Off Timeout vs. Supply Voltage and Temperature 400 -40°C 350 300 250 200 150 +25°C 100 50 2.7 3.1 3.5 3.9 4.3 Supply Voltage (V) Transition of LED Current (Group B = 1.8mA; Group A ...
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TM SwitchReg Functional Block Diagram VIN IN OV EN/SET Functional Description The AAT1235 consists of a controller for the step-up switching converter and its power switch, and five regu- lated current sinks each programmable at 16 levels into two groups, ...
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... Constant Current Output Level Settings and AS 2 The LED current sink level of each group and the on/off status of each channel is controlled by AnalogicTech’s AS Cwire serial digital input. Since each current sink is 2 programmable, no PWM or additional control circuitry is needed to control LED brightness. This feature greatly ...
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TM SwitchReg the T timeout period, a burst of rising edges signifying LAT data, and a T timeout for the data registers. Once an LAT address is set, then multiple writes to that address are allowed where only data is ...
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TM SwitchReg AS Cwire Serial Interface Timing 2 EN/SET Address Data Reg 1 Data Reg 2 Application Information Channel Disable Tie all unused channels to AGND. On start-up, these channels will be automatically disabled. LED Selection Although the AAT1235 is ...
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... I with increasing conduction period. Manufacturers’ datasheets should be reviewed carefully to verify reli- ability under peak loading conditions. The diode’s pub- lished current rating may not reflect actual operating conditions and should be used only as a comparative measure between similarly rated devices ...
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TM SwitchReg R2 187k VIN JP6 Enable/Set C1 2.2μF R3 12.1k Figure 3: A AAT1235-based High Efficiency White LED Driver Schematic. Estimating Schottky Diode Power Dissipation The switching period is divided between ON and OFF time intervals: ...
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TM SwitchReg Manufacturer Part Number Diodes, Inc. B0520WS ON Semi MBR130LSFT ON Semi MBR0530T Table 8: Typical Surface Mount Schottky Rectifiers for Various Output Loads. External Schottky diode junction temperature should be below 110ºC, and may vary depending on application ...
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TM SwitchReg To ensure high reliability, the inductor case temperature should not exceed 100ºC. In some cases, PCB heatsink- ing applied to the LIN node (non-switching) can improve the inductor’s thermal capability. However the case of adding extra ...
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TM SwitchReg PCB Layout Guidelines Boost converter performance can be adversely affected by poor layout. Possible impact includes high input and output voltage ripple, poor EMI performance, and reduced operating efficiency. Every attempt should be made to optimize the layout ...
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TM SwitchReg Figure 6: Exploded View of AAT1235 Evaluation Board Top Side Layout Detailing Plated Through Vias. 18 High Efficiency White LED Drivers for Backlight and Keypad ...
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... High Efficiency White LED Drivers for Backlight and Keypad Part Number (Tape and Reel) 1 TKXYY TDFN34-16 1.600 ± 0.050 Bottom View (4x) Pin 1 Indicator (optional) 0.229 ± 0.051 PRODUCT DATASHEET AAT1235 2 AAT1235IRN-T1 Detail "A" 0.350 ± 0.100 C0.3 Detail "A" 19 ...
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... 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 specifi cations 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 fi ...