AP5725

Document overview

  • Manufacturer or author: Diodes Incorporated
  • PDF pages: 17

Technical content

Features

  • High efficiency: 84% typical
  • Fast 1.2MHz switching frequency
  • Current limit and UVLO protections
  • Internal thermal shutdown
  • Internal Over Voltage Protection
  • Integrated soft-start function
  • SOT26, TSOT23-6 and DFN2020C-6: Available in “Green” Molding Compound (No Br, Sb)
  • Lead Free Finish/ RoHS Compliant (Note 1)

Applications

  • Cellular Phones
  • PDAs, Hand held Computers
  • Digital Cameras
  • MP3 Players
  • GPS Receivers Notes: 1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at http://www.diodes.com/products/lead_free.html. Typical Application Circuit VIN SW EN GND FB AP5725 COUT 1uF RSET 22uH D1 VIN CIN 1uF OVP 2~6 LEDs PWM Dimming OFFON

Figure 1. Typical Application Circuit

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 2 of 17 www.diodes.com July 2010 © Diodes Incorporated Pin Descriptions Pin Name Description SW Switch Pin. Connect inductor/diode here. Minimize trace area at this pin to reduce EMI. GND GND pin. FB Feedback Pin. Reference voltage is 0.25V. Connect cathode of lowest LED and a sense resister here. Calculate resistor value according to the formula: RSET = 0.25V / ILED EN Converter On/Off Control Input. A high input at EN turns the converter On, and a low input turns it off. If On/Off control is not needed, connect EN to the input source for automatic startup. The EN pin cannot be left floating. OVP Output Voltage detect pin for over voltage protection. VIN Input Supply Pin. Must be locally bypassed with 1 μF or 2.2μF to reduce input noise. Functional Block Diagram 1.2MHz Oscillator RAMP Generator Σ - + - + VREF 0.25VVIN 3FB Rc Cc Comparator CONTROL LOGIC Driver SW

2 GND

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 3 of 17 www.diodes.com July 2010 © Diodes Incorporated Absolute Maximum Ratings Symbol Parameter Rating Unit VIN VIN Pin Voltage -0.3~7 V VSW SW Voltage -0.3~34 V VOVP OVP Pin Voltage -0.3~35 V VFB Feedback Pin Voltage -0.3~7 V EN EN -0.3~7 V TJ(MAX) Maximum Junction Temperature 150 oC TLEAD Lead Temperature 300 oC TST Storage Temperature Range -65 to +150 oC Caution: Operation above the absolute maxi mum ratings can cause device failure. These values, therefore, must not be exceeded under any condition. Operation at the absolute maximum rating for extended periods, may reduce device reliability. Recommended Operating Conditions Symbol Parameter Min Max Unit VIN Input Voltage 2.7 5.5 V TJ Operating Junction Temperature -40 125 oC TA Operating Ambient Temperature -40 85 oC

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 4 of 17 www.diodes.com July 2010 © Diodes Incorporated Electrical Characteristics (VIN = 3.6V, TA = 25°C, unless otherwise specified.) Symbol Parameter Conditions Min Typ. Max Unit System Supply Input VIN Operating Input Voltage 2.7 - 5.5 V UVLO Under Voltage Lockout - 2.2 2.4 V Under Voltage Lockout Hysteretic - 85 - mV IQ Quiescent Current FB=0.35V, No Switching - 500 - μA ISD Shutdown Current VEN < 0.4V - 0.1 1 μA Oscillator FOSC Operation Frequency 1 1.2 1.4 MHz Dmax Maximum Duty Cycle 86 90 - % Reference Voltage VFB Feedback Voltage 0.225 0.25 0.275 V IFB FB Pin Bias Current 10 45 100 nA MOSFET Rds(on) On Resistance of MOSFET - 0.95 1.2 Ω IOCP Switching Current Limit Normal Operation - 750 - mA Control and Protection EN Voltage High ON 1.5 - - V EN Voltage Low OFF - - 0.4 V IEN EN Pin Pull Low Current - 4 6 μA OVP OVP Threshold 26 30 34 V θJA Thermal Resistance Junction-to- Ambient SOT26 (Note 2) 162 oC/WTSOT23-6 (Note 2) 152 DFN2020C-6 (Note2) 200 θJC Thermal Resistance Junction-to- Case SOT26 (Note 2) 36 oC/WTSOT23-6 (Note 2) 32 DFN2020C-6 (Note 2) 30 Notes: 2. Test condition for SOT26, TSOT23-6 and DFN2020C-6: Device mounted on FR-4 substrate, single-layer PC board, 2oz copper, with minimum recommended pad layout

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 5 of 17 www.diodes.com July 2010 © Diodes Incorporated Typical Performance Characteristics (6 LEDs ; VIN = 3.6V ; IOUT = 25mA) VIN vs. Shutdown Current 0.2 0.4 0.6 0.8 2 . 533 . 544 . 555 . 5 VIN (V) Shutdown Current(uA) VIN vs. Quiescent Current 100 200 300 400 500 600 700 2.5 3 3.5 4 4.5 5 5.5VIN (V) Quiescent Current(uA) VIN vs. Frequency 1.05 1.1 1.15 1.2 1.25 2.5 3 3.5 4 4.5 5 5.5 VIN (V) Frequency(MHz) VIN vs. Max Duty 100 2 . 533 . 544 . 555 . 5 V IN(V) Max Duty(%) VIN vs. Feedback Voltage 0.2 0.22 0.24 0.26 0.28 0.3 2.5 3 3.5 4 4.5 5 5.5 VIN (V) Feedback Voltage(V) IOUT vs. Feedback Voltage 0.2 0.22 0.24 0.26 0.28 0.3 0 1 02 03 04 05 0 IOUT (mA) Feedback Voltage(V)

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 6 of 17 www.diodes.com July 2010 © Diodes Incorporated Typical Performance Characteristics (Continued) VIN vs. OVP Threshold 2.5 3 3.5 4 4.5 5 5.5 VIN (V) OVP Threshold(V) Temperature vs. Shutdown Current 0.2 0.4 0.6 0.8 -50 -25 0 25 50 75 100 125 Shutdown Current(uA) Temperature (℃) Temperature vs. OVP Threshold -50 -25 0 25 50 75 100 125 Temperature (℃) OVP Threshold(V) Temperature vs. Frequency 0.2 0.5 0.8 1.1 1.4 1.7 -50 -25 0 25 50 75 100 125 Temperature ( ℃) Frequency (MHZ) VIN = 3.6V VIN = 4.2V Temperature vs. Feedback Voltage 0.23 0.24 0.25 0.26 0.27 0.28 -50 -25 0 25 50 75 100 125 Temperature( ℃) Feedback Voltage(V) VIN = 3.6V VIN = 4.2V

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 7 of 17 www.diodes.com July 2010 © Diodes Incorporated Typical Performance Characteristics (Continued) IOUT vs. Efficiency 0 5 10 15 20 25 30 IOUT (mA) Efficiency(%)

4 LEDs ; L = 22uH

VIN = 4.2V VIN = 3.6V IOUT vs. Efficiency 0 5 10 15 20 25 30 I OUT (mA) Efficiency(%)

6 LEDs ; L = 22uH

VIN = 3.6V VIN = 4.2V VIN vs. Efficiency 100 2.5 3 3.5 4 4.5 5 VIN (V) Efficiency(%)

3 LEDs

6 LEDs

4 LEDs

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 8 of 17 www.diodes.com July 2010 © Diodes Incorporated Typical Performance Characteristics (Continued) VOUT Ripple VIN = 3.6V; 4 LEDs ; IOUT = 30mA VOUT Ripple VIN = 3.6V; 6 LEDs ; IOUT = 30mA POWER ON VIN = 3.6V; 6 LEDs ; IOUT = 30mA POWER OFF VIN = 3.6V; 6 LEDs ; IOUT = 30mA VEN VEN VOUT VOUT VOUT Irushi Irushin g SW SW VOUT

should also exceed the peak input current, especially for high load current applications (like 3S8P). recommended). The formula and table for RSET selection are shown below. Table 1. RSET Resistor Value Selection

voltage protection is activated and SW pin stops switching. Figure 2. LED Driver with Open-Circuit Protection

  1. Using a PWM Signal to EN Pin

corresponds to full current. The typical frequency range of the PWM signal is below 2kHz.

Table 2. Suggested Inductors Table 3. Suggested Capacitors for CIN and COUT Table 4. Suggested Diodes Table 5. Suggested Resistor Table 6. Suggested W-LED

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 13 of 17 www.diodes.com July 2010 © Diodes Incorporated

Ordering Information

7 : Tape & Reel Green G : Green FDC : DFN2020C-6 W : SOT26 WU : TSOT23-6 Device Package Code Packaging (Note 3) 7” Tape and Reel Quantity Part Number Suffix AP5725WG-7 W SOT26 3000/Tape & Reel -7 AP5725WUG-7 WU TSOT23-6 3000/Tape & Reel -7 AP5725FDCG-7 FDC DFN2020C-6 3000/Tape & Reel -7 Notes: 3. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at http://www.diodes.com/datasheets/ap02001.pdf. Marking Information (1) SOT26 and TSOT23-6 1 2 3 XX Y WX XX : Identification Code Y : Year 0~9 X : A~Z : Green ( Top View ) W : Week : A~Z : 1~26 week; a~z : 27~52 week; z represents 52 and 53 week Part Number Package Identification Code AP5725WG-7 SOT26 FC AP5725WUG-7 TSOT23-6 GC (2) DFN2020C-6 ( Top View ) XX Y : Year : 0~9 X : A~Z : Green XX : Identification Code W : Week : A~Z : 1~26 week; a~z : 27~52 week; z represents 52 and 53 week Y W X Part Number Package Identification Code AP5725FDCG-7 DFN2020C-6 GC

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 14 of 17 www.diodes.com July 2010 © Diodes Incorporated Package Outline Dimensions (All Dimensions in mm) (1) Package Type: SOT26 (2) Package Type: TSOT23-6

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 15 of 17 www.diodes.com July 2010 © Diodes Incorporated Package Outline Dimensions (Continued) (3) Package Type: DFN2020C-6

0.10 M C A B

B 0.25 Bottom View A A 0/0.05 0.57/0.63 0.15max.C

0.25 B2x-

0.08 C 0.10 C Seating plane 1.55/1.75 1.95/2.075 0.25/0.35 0.25/0.350.65nom. 0.86/1.06 1.95/2.075 Pin#1 ID R0.1 Marking 0.43mon. (Active area depth) R0.15 Land Pattern Recommendation (Unit:mm) Top View 0.65 0.45 0.37 1.59 0.9

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 16 of 17 www.diodes.com July 2010 © Diodes Incorporated Taping Orientation For DFN2020C-6

WHITE LED STEP-UP CONVERTER AP5725 Document number: DS31844 Rev. 3 - 2 17 of 17 www.diodes.com July 2010 © Diodes Incorporated 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 described herein. Diodes Incorporated does not assume any liabi lity arising out of the application or use of this document or an y product described herein; neither does Diodes Incorporated convey any license under its patent or trademark rights, nor the rights of othe rs. Any Customer or user of this document or products desc ribed 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 what soever in respect of any prod ucts purchased through unauthorized sales channel. Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall indemnify and hold Diodes Incorporated and its representatives har mless 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 specifica lly not authorized for use as critical co mponents 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 properly 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 ramifications of their life support dev ices or systems, and acknowledge and agree that they are solely responsi ble for all legal, regulatory and safety-related requirements concerning their products and any use of Diode s Incorporated products in such safety-cri tical, life support devices or systems, notwithstanding any devices- or systems-related information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated and its repr esentatives against any damages ar ising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright © 2010, Diodes Incorporated www.diodes.com