AP8803

Document overview

  • Manufacturer or author: Diodes Incorporated
  • PDF pages: 10

Technical content

Features

  • LED Driving Current up to 1A
  • High Efficiency Up to 92%
  • Operating Input Voltage Up to 30V
  • High Switching Frequency Up to 700kHz
  • PWM/DC Input for Dimming Control
  • Built-In Output Open-Circuit Protection
  • TSOT25: Available in “Green” Molding Compound (No Br, Sb) with lead Free Finish/ RoHS Compliant ƒ Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) ƒ Halogen and Antimony Free. “Green” Device (Note 3) Pin Assignments 3 4 SET VIN CTRL GND SW Top View Notes: 1. No purposely added lead. Fully EU Directiv e 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See http://www.diodes.com for more in formation about Diodes Incorporated’s definitions of Halogen and Antimony free, "Green" and Lead-Free. 3. Halogen and Antimony free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and <1000ppm antimony compounds. Typical Applications Circuit RSET AP8803 CTRL VIN SET SW GND 12V_DC

Document number: DS31970 Rev. 5 - 2 2 of 10 www.diodes.com August 2012 © Diodes Incorporated AP8803 Pin Descriptions Pin Name Function SW Switch Pin. Connect inductor/freewheeling diode here , minimizing track length at this pin to reduce EMI. GND GND pin SET Set Nominal Output Current Pin. Configure the output current of the device. CTRL Dimming and On/Off Control Input.

  • Leave floating for normal operation. (VCTRL = VREF = 1.25V giving nominal average output current IOUTnom = 0.1/RS)
  • Drive to voltage below 0.2V to turn off output current
  • Drive with DC voltage (0.3V < V CTRL < 1.25V) to adjust output current from 25% to 100% of IOUTnom
  • Input voltage of 0.2V or lower forces the device into low current standby mode and shuts off the output. A PWM signal allows the output current to be adjusted above or below the level set by the resistor connected to SET input pin. VIN Input Supply Pin. Must be locally decoupled to GND with > 2.2µF X7R ceramic capacitor. Functional Block Diagram Absolute Maximum Ratings (@TA = +25°C, unless otherwise specified.) Symbol Parameter Rating Unit VIN Continuous VIN pin voltage -0.3 to +30 V Transient (t < 0.5s) 40 VSW SW voltage -0.3 to +30 V Transient (t < 0.5s) 40 VCTRL CTRL pin input voltage -0.3 to +6 V ISW Switch current 1.25 A ESDHBM Human Body Model ESD 500 V ESDMM Machine Model ESD <100 V TJ Junction Temperature 150 °C TLEAD Lead Temperature Soldering 300 °C TST Storage Temperature Range -65 to +150 °C Caution: Stresses greater than the 'Absolute Maximum Ratings' sp ecified above, may cause permanent damage to the device. These are stress ratings only; functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time. Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when handling and transporting these devices

Document number: DS31970 Rev. 5 - 2 3 of 10 www.diodes.com August 2012 © Diodes Incorporated AP8803 Recommended Operating Conditions (@TA = +25°C, unless otherwise specified.) Symbol Parameter Min Max Unit VIN Operating Input Voltage 8.0 30 V VCTRLH Voltage High 0.3 2.5 V VCTRLL Voltage Low 0.25 V ISW Continuous Switch Current (Note 5) 1 A TA Ambient Temperature Range -40 +125 °C Duty Cycle Using Inductor ≥ 100µH (Note 4) 0.1 0.95 Notes: 4. For most applications the LED current will be within 8% over the duty cycle range specified. Duty cycle accuracy is also dependent on propagation delay. Smaller size inducto rs can be used but LED current accuracy may be greater than 8% at extremes of duty cycle. This is most noticeable at low duty cycles (less than 0.1) or when the input voltage is high and only one LED is being driven. 5. Refer to Figure 8 for the device derating curve. Electrical Characteristics (@TA = +25°C, unless otherwise specified.) Symbol Parameter Conditions Min Typ Max Unit VINSU Internal Regulator Start-Up Threshold V IN rising 5.65 V VINSD Internal Regulator Shutdown Threshold V IN falling 5.55 V IQ Quiescent Current CTRL pin floating f = 250kHz 1.8 5 mA VTHD Internal Threshold Voltage 92 100 108 mV ISET SET Pin Input Current VSET = VIN -0.1 1.25 10 µA VREF Internal Reference Voltage 1.25 V RDS(on) On Resistance of MOSFET ISW = 1A 0.5 1 Ω ISW Continuous Switch Current (Note 5) 1 A ISW_Leakage Switch Leakage Current 8 µA fOSC Switching Frequency 0.7 MHz θJA Thermal Resistance Junction-to- Ambient TSOT25 (Note 6) 125 °C/W Notes: 5. Refer to Figure 8 for the device derating curve. 6. Test condition for TSOT25: Device mounted on FR-4 PCB, 25mm x 25mm, 2oz copper, minimum recommended pad layout on top layer and thermal vias to bottom layer ground plane. For better thermal performance, larger copper pad for heat-sink is needed.

Document number: DS31970 Rev. 5 - 2 6 of 10 www.diodes.com August 2012 © Diodes Incorporated AP8803 Application Information (cont.) LED Current Dimming The LED current can be dimmed in two ways; 1. Analog Dimming: Where a DC voltage is applied to the CTRL pin. or 2. PWM Dimming: Where a Pulse Width Modulated (PWM) signal is applied to the CTRL pin. Analog Dimming If the CTRL pin is driven by an external voltage (lower than 2.5V), the average LED current is: SET THD REF CTRL LED R V V VI = A DC signal from 0.3V to 2.5V applied to the CTRL pin will vary t he LED current from 24% to 200% of nominal LED current. This g ives an approximate 8:1 dimming range; care, should be ex ercised when overdriving the CTRL pin to 200% of nominal LED current not to ex ceed the power dissipation of the package. The graph in Figure 4 shows values of nominal average output current for 3 values of current setting resistor (R SET) in the typical application circuit shown on Figure 1, for different voltages applied on the CTRL pin. It can be used to determine the R SET value based on the desired LED current and the condit ion of the CTRL pin (floating or driven with an external DC voltage lower than 2.5V and higher than 0.2V). LED current Versus RSET and VCTRL 0.2 0.3 0.39 0.47 30.82 1 1.5 2 3 0.82 0.75 21.5 0.75 0.47 0.3 0.1 0.15 200 400 600 800 1000 1200 RSE T value [Ohms ] LED Current [mA] LED current @ VCTRL = 1.25V LED current @ VCTRL = 2.5V LED current @ VCTRL = 0.625V Figure 4 LED Current Setting vs. RSET and VCTRL

Document number: DS31970 Rev. 5 - 2 9 of 10 www.diodes.com August 2012 © Diodes Incorporated AP8803

Ordering Information

Part Number Package Code Packaging 7” Tape and Reel Quantity Part Number Suffix AP8803WTG-7 WT TSOT25 3000/Tape & Reel -7 Marking Information Part Number Package Identification Code AL8803WT-7 TSOT25 AY Package Outline Dimensions (All dimensions in mm.) Please see AP02002 at http://www.diodes.com/datasheets/ap02002.pdf for latest version. TSOT25 Dim Min Max Typ A − 1.00 − A1 0.01 0.10 − A2 0.84 0.90 − D − − 2.90 E − − 2.80 E1 − − 1.60 b 0.30 0.45 − c 0.12 0.20 − e − − 0.95 e1 − − 1.90 L 0.30 0.50 L2 − − 0.25 θ 0° 8° 4° θ1 4° 12° − All Dimensions in mm c L E1 E D e 5x b θ 4x 1 θ A XX : Identification Code Y : Year 0~9 W : Week: A~Z: 1~26 week a~z: 27~52 week; z represents 52 and 53 week

Document number: DS31970 Rev. 5 - 2 10 of 10 www.diodes.com August 2012 © Diodes Incorporated AP8803 Suggested Pad Layout Please see AP02001 at http://www.diodes.com/datasheets/ap02001.pdf for the latest version. IMPORTANT NOTICE DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION). Diodes Incorporated and its subsidiaries rese rve the right to make modifications, enhanc ements, improvements, corrections or ot her changes without further notice to this document and any product descri bed herein. Diodes Incorporated does not assume any liability arising out of the application or use of this document or an y product described herein; neither does Di odes Incorporated convey any license under its patent or trademark rights, nor the rights of others. Any Customer or us er of this document or products described herein in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on Diodes Incorporated website, harmless against all damages. Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthoriz ed sales channel. Should Customers purchase or use Diodes Inco rporated products for any unintended or una uthorized application, Customers shall i ndemnify and hold Diodes Incorporated and its representativ es harmless against all claims, damages, expenses, and attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized application. Products described herein may be covered by one or more United States, international or foreign patents pending. Product names and markings noted herein may also be covered by one or more United States, international or foreign trademarks. LIFE SUPPORT Diodes Incorporated products are specifically not authorized for use as critical component s in life support devices or systems without the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein: A. Life support devices or systems are devices or systems which: 1. are intended to implant into the body, or 2. support or sustain life and whose failure to perform when proper ly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in significant injury to the user. B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or to affect its safety or effectiveness. Customers represent that they have all necessary expertise in the safety and regulatory ramifi cations of their life support dev ices or systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any use of Diodes Incorporated products in such safety-critical, life support devices or systems, notwithstanding any devices- or s ystems-related information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporate d and its representatives against any damages arising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright © 2012, Diodes Incorporated www.diodes.com Dimensions Value (in mm) C 0.950 X 0.700 Y 1.000 Y1 3.199 C C X (5x) Y (5x)