Electronic Components Datasheet Search |
|
AAT3167IFO-T1 Datasheet(PDF) 11 Page - Advanced Analog Technology, Inc. |
|
AAT3167IFO-T1 Datasheet(HTML) 11 Page - Advanced Analog Technology, Inc. |
11 / 14 page AAT3167 High Efficiency 1X/1.5X/2X Charge Pump for White LED Applications 3167.2007.03.1.4 11 Applications Information LED Selection Although the AAT3167 is designed for driving white LEDs, the device also can be used to drive most types of LEDs with forward voltage specifications ranging from 2.0V to 4.7V. LED applications may include main and sub-LCD display backlighting, camera photo-flash applications, color (RGB) LEDs, infrared diodes for remotes, and other loads benefiting from a controlled output current generat- ed from a varying input voltage. Since the D1 to D5 input current sinks are matched with negligible voltage dependence, the LED brightness will be matched regardless of the specific LED forward voltage (VF) levels. In some instances (e.g., in high luminous output applications such as photo flash), it may be neces- sary to drive high-VF type LEDs. The low-dropout current sinks in the AAT3167 make it capable of driving LEDs with forward voltages as high as 4.7V at full current from an input supply as low as 3.0V. Outputs can be paralleled to drive high-current LEDs without complication. Device Switching Noise Performance The AAT3167 operates at a fixed frequency of approximately 1MHz to control noise and limit har- monics that can interfere with the RF operation of cellular telephone handsets or other communica- tion devices. Back-injected noise appearing on the input pin of the charge pump is 20mV peak-to- peak, typically ten times less than inductor-based DC/DC boost converter white LED backlight solu- tions. The AAT3167 soft-start feature prevents noise transient effects associated with inrush cur- rents during start-up of the charge pump circuit. Capacitor Selection Careful selection of the four external capacitors (CIN, C1, C2, COUT) is important because they will affect turn-on time, output ripple, and transient per- formance. Optimum performance will be obtained when low equivalent series resistance (ESR) (<100m Ω) ceramic capacitors are used. A value of 1µF for all four capacitors is a good starting point when choosing capacitors. If the LED current sources are programmed only for light current lev- els, then the capacitor size may be decreased. AS2Cwire Serial Interface Timing Address Data 1 EN/SET 2 17 18 Address Data Reg 1 Data Reg 2 1 2 . . . n <= 16 0 1 0 0 n THI TLO TLAT TLAT |
Similar Part No. - AAT3167IFO-T1 |
|
Similar Description - AAT3167IFO-T1 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |