AP3019AKTR-G1

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AP3019A Document number: DS41298 Rev. 3 - 2 1 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T WHITE LED STEP-UP CONVERTER Description The AP3019A is an inductor-based DC/DC converter designed to drive up to eight white LEDs in series for backlight. Only one feedback resistor is needed to control the LED current and obtain required brightness. A constant frequency 1.2MHz PWM control scheme is employed in this IC, which means tiny external components can be used. Specifically, 1mm tall inductor and 0.22F output capacitor for a typical application is sufficient. Additionally, the Schottky diode in boost circuit is integrated on this chip. The AP3019A also provides a disable pin to ease its use for different systems. The output over-voltage protection is implemented in AP3019A. When any LED is broken or in other abnormal conditions, the output voltage will be clamped. The AP3019A is available in standard SOT-23-6 and TSOT-23-6 packages. Features  Inherently Uniform LED Current  High Efficiency up to 84%  No Need for External Schottky Diode  Output Over-voltage Protection (OVP)  Fixed 1.2MHz Switching Frequency  Uses Tiny 1mm Tall Inductor  Requires only 0.22F Output Capacitor Pin Assignments (Top View) 1 2 3 4 5 Pin 1 Mark 6SW GND FB CTRL VIN VOUT K/KT Package (SOT-23-6/TSOT-23-6) Applications  Cellular Phones  Digital Cameras  LCD Modules  GPS Receivers  PDAs, Handheld Computers

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AP3019A Document number: DS41298 Rev. 3 - 2 2 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Typical Applications Circuit 22 H 1F 0.22F 10 V IN SW V OUT FB GND CTRL AP3019AControlSignal V IN  3V L C IN C OUT 1 6 4 5 2 3 C: X5R or X7R dielectric L: SUMIDA CDRH5D28R-220NC or equivalent This circuit can work in full temperature Pin Descriptions Pin Number Pin Name Function 1 SW Switch pin. Connect external inductor 2 GND Ground 3 FB Voltage feedback pin. Reference voltage is 200mV 4 CTRL Shutdown and dimming pin. Connect to 1.8V or higher to enable device; Connect to 0.5V or less to disable device; Connect to a PWM signal to achieve LEDs brightness dimming 5 VOUT Output pin. Connect to the cathode of internal Schottky diode 6 VIN Input supply pin. Must be connected to a local bypass capacitor

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AP3019A Document number: DS41298 Rev. 3 - 2 3 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Functional Block Diagram Q1A2 A1 R S Q 1.2 MHz OSCILLATOR RAMP GENERATOR VREF 3 6 4 2 5 DRIVER 1.25 V COMPARATOR OVP 200mV 1 SOFT START FB SW VOUT GND CTRL VIN Absolute Maximum Ratings (Note 1) Note 1. Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “Recommended Operating Conditions” is not implied. Exposure to “Absolute Maximum Ratings” for extended periods may affect device reliability. Symbol Parameter Rating Unit VIN Input Voltage 20 V VSW SW Pin Voltage 38 V VFB Feedback Voltage 20 V VCTRL CTRL Pin Voltage 20 V JA Thermal Resistance (Junction to Ambient, No Heat Sink) 265 C/W TJ Operating Junction Temperature +150 C TSTG Storage Temperature Range -65 to +150 C TLEAD Lead Temperature (Soldering, 10sec) +260 C – ESD (Machine Model) 250 V – ESD (Human Body Model) 2000 V

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AP3019A Document number: DS41298 Rev. 3 - 2 4 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Recommended Operating Conditions Symbol Parameter Min Max Unit TOP Operating Temperature Range -40 +85 C VIN Input Voltage 2.5 16 V VCTRL CTRL Pin Voltage – 16 V Electrical Characteristics (@VIN =3V, VCTRL=3V, TA =+25°C, unless otherwise specified.) Symbol Parameter Condition Min Typ Max Unit VIN (MIN) Minimum Operating Voltage – 2.5 – – V VIN (MAX) Maximum Operating Voltage – – – 16 VFB Feedback Voltage (Note 2) IOUT=20mA, 4 LEDs, TA=-40 o C to +85 o C 188 200 212 mV IFB FB Pin Bias Current – – 35 100 nA IQ Quiescent Current VFB=VIN, No Switching 1.5 2.5 3.2 mA ISHDN Shutdown Quiescent Current VCTRL=0V 2.0 4.0 6.0 A f Switching Frequency – 0.9 1.2 1.5 MHz DMAX Maximum Duty Cycle – 90 93 – % ILIMIT Switch Current Limit (Note 3) D=40% – 550 – mA D=80% – 550 – VCESAT Switch VCE Saturation Voltage ISW=250mA – 360 – mV – Switch Leakage Current VSW=5V – 0.01 5 A VCTRL CTRL Pin Voltage High 1.8 – – V Low – – 0.5 ICTRL CTRL Pin Bias Current – – 100 – A VOV OVP Voltage – – 30 – V VDROP Schottky Forward Drop ID=150mA – 0.7 – V – Schottky Leakage Current VR(Reverse Voltage)=23V – 0.1 4 A VR(Reverse Voltage)=27V – – 150 t Soft Start Time – – 300 – s JC Thermal Resistance (Junction to Case) SOT-23-6 – 60 – C/W TSOT-23-6 – 60 – Notes: 2. The bold type specifications of full temperature range are guaranteed by design (GBD). 3. The switch current limit is related to duty cycle. Please refer to Figure Current Limit vs. Duty Cycle for detail.

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AP3019A Document number: DS41298 Rev. 3 - 2 5 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Performance Characteristics (WLED forward voltage (VF) is 3.45V at IF=20mA, unless otherwise noted.) Efficiency vs. Junction Temperature Efficiency vs. Input Voltage Efficiency vs. LED’s Number Schottky Forward Current vs. Schottky Forward Drop Shutdown Quiescent Current vs. Input Voltage Quiescent Current vs. Input Voltage -50 -25 0 25 50 75 100 73 74 75 76 77 78 79 80 81 82 83 V IN =3.6V, I OUT =20mA, 8 LEDs C IN =1F, C OUT =0.22F, L=22H E ff ic ie n c y ( % ) Junction Temperature ( o C) 3.0 3.5 4.0 4.5 5.0 70 72 74 76 78 80 82 84 86 I OUT =20mA, 8 LEDs,T A =+25 O C C IN =1F, C OUT =0.22F, L=22H E ff ic ie n c y ( % ) Input Voltage (V) 2 3 4 5 6 7 8 76 77 78 79 80 81 82 83 84 85 86 V IN =3.6V, I OUT =20mA,T A =+25 O C C IN =1F, C OUT =0.22F, L=22H LED's Number E ff ic ie n c y ( % ) 0 200 400 600 800 1000 0 50 100 150 200 250 300 350 S c h o tt k y F o rw a rd C u rr e n t (m A ) Schottky Forward Drop (mV) 2 4 6 8 10 12 14 16 0 5 10 15 20 25 30 S h u td o w n Q u ie s c e n t C u rr e n t ( A ) Input Voltage (V) T A =+25 O C 0 2 4 6 8 10 12 14 16 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Q u ie s c e n t C u rr e n t (m A ) Input Voltage (V) T A =-50 O C T A =+25 O C T A =+100 O C

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AP3019A Document number: DS41298 Rev. 3 - 2 6 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Performance Characteristics (WLED forward voltage (VF) is 3.45V at IF=20mA, unless otherwise noted.) (Cont.) Input Current in Output Open Circuit vs. Input Voltage Frequency vs. Junction Temperature Feedback Voltage vs. Junction Temperature Schottky Forward Drop vs. Junction Temperature Schottky Leakage Current vs. Junction Temperature Current Limit vs. Duty Cycle -50 -25 0 25 50 75 100 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40 F re q u e n c y ( M H z ) Junction Temperature ( o C) 2.5 3.0 3.5 4.0 4.5 5.0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 In p u t C u rr e n t (m A ) Input Voltage (V) -50 -25 0 25 50 75 100 190 192 194 196 198 200 202 204 206 208 210 F e e d b a c k V o lt a g e ( m V ) Junction Temperature ( o C) -50 -25 0 25 50 75 100 0.60 0.62 0.64 0.66 0.68 0.70 0.72 0.74 0.76 0.78 0.80 S c h o tt k y F o rw a rd D ro p ( V ) Junction Temperature ( o C) I D =150mA -50 -25 0 25 50 75 100 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 S c h o tt k y L e a k a g e C u rr e n t ( A ) Junction Temperature ( o C) V R =10V V R =16V V R =23V 30 40 50 60 70 80 90 100 200 300 400 500 600 700 -50 O C +25 O C +100 O C C u rr e n t L im it (m A ) Duty Cycle (%)

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AP3019A Document number: DS41298 Rev. 3 - 2 7 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T LED 1 I mV200 R = Performance Characteristics (WLED forward voltage (VF) is 3.45V at IF=20mA, unless otherwise noted.) (Cont.) Saturation Voltage vs. Switch Current CTRL Pin Voltage vs. Junction Temperature Application Information Operation The AP3019A is a boost DC-DC converter which uses a constant frequency, current mode control scheme to provide excellent line and load regulation. Operation can be best understood by referring to the Figure Functional Block Diagram of AP3019A. At the start of each oscillator cycle, the SR latch is set and switch Q1 turns on. The switch current will increase linearly. The voltage on sense resistor is proportional to the switch current. The output of the current sense amplifier is added to a stabilizing ramp and the result is fed into the non-inversion input of the PWM comparator A2. When this voltage exceeds the output voltage level of the error amplifier A1, the SR latch is reset and the switch is turned off. It is clear that the voltage level at inversion input of A2 sets the peak current level to keep the output in regulation. This voltage level is the output signal of error amplifier A1, and is the amplified signal of the voltage difference between feedback voltage and reference voltage of 200mV. So, a constant output current can be provided by this operation mode. L1 C1 C2 R1 V IN SW V OUT FB GND CTRL AP3019AControl Signal V IN  3V 1 6 4 5 2 3 Typical Application Circuit to Decide R1 LED Current Control Refer to Figure Typical Application Circuit to Decide R1, the LED current is controlled by the feedback resistor R1. LEDs' current accuracy is determined by the regulator's feedback threshold accuracy and is independent of the LED's forward voltage variation. So the precise resistors are preferred. The resistance of R1 is in inverse proportion to the LED current since the feedback reference is fixed at 200mV. The relation for R1 and LED current can be expressed as below: 50 100 150 200 250 300 50 100 150 200 250 300 350 400 450 S a tu ra ti o n V o lt a g e ( m V ) Switch Current (mA) -50 -25 0 25 50 75 100 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 C T R L P in V o lt a g e ( V ) Junction Temperature ( O C) Falling Edge Rising Edge

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AP3019A Document number: DS41298 Rev. 3 - 2 8 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Application Information (Cont.) Over Voltage Protection The AP3019A has an internal open-circuit protection circuit. When the LEDs are disconnected from circuit or fail open, the output voltage is clamped. The AP3019A will switch at a low frequency, and minimize input current. Soft Start The AP3019A has an internal soft start circuit to limit the inrush current during startup. The time of startup is controlled by internal soft start capacitor. Please refer to Figure Soft Start Waveform. IIN 100mA/div VOUT 5V/div VCTRL 2V/div Time 100s/div VFB 100mV/div Soft Start Waveform VIN=3.6V, 5 LEDs, ILED=20mA Dimming Control Two typical types of dimming control circuit are present as below. First, controlling CTRL Pin voltage to change operation state is a good choice. Second, changing the feedback voltage to get appropriate duty and luminous intensity is also useful. (1) Adding a Control Signal to CTRL Pin Add a PWM Signal to CTRL pin directly. The AP3019A is turned on or off by the PWM signal when it is applied on the CTRL pin. The typical frequency of this PWM signal can be up to 2kHz. Please refer to Figure Dimming Control Using a PWM Signal in CTRL Pin. Dimming Control Using a PWM Signal in CTRL Pin (2) Changing the Effective Feedback Voltage There are three methods to change the effective feedback voltage. First, adding a constant DC voltage through a resistor divider to FB pin can control the dimming. Changing the DC voltage or resistor between the FB Pin and the DC voltage can get appropriate luminous intensity. Comparing with all kinds of PWM signal control, this method features a stable output voltage and LEDs current. Please refer Figure Dimming Control Using DC Voltage. Dimming Control Using DC Voltage AP3019A CTRL up to 2kHz R1 10 FB AP3019A R2 5K R3 90K VDC Effective Feedback Voltage

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AP3019A Document number: DS41298 Rev. 3 - 2 9 of 12 www.diodes.com August 2018 © Diodes Incorporated AP3019A N E W P R O D U C T Application Information (Cont.) Second, using a filtered PWM signal can do it. The filtered PWM signal can be considered as a varying and adjustable DC voltage. R1 10 FB AP3019A R2 5K R3 90K PWM R4 10K C 0.1F Effective Feedback Voltage Dimming Control Using a Filtered PWM Voltage Third, using a logic signal can change the feedback voltage. For example, the FB pin is connected to the GND through a MOSFET and a resistor. And this MOSFET is controlled a logic signal. The luminous intensity of LEDs will be changed when the MOSFET turns on or off. R1 FB AP3019A R2 Logic Signal 2N7002 Effective Feedback Voltage Dimming Control Using Logic Signal Ordering Information AP3019A X X - X PackingPackageProduct Name K: SOT-23-6 KT: TSOT-23-6 RoHS/Green G1:RoHS Compliant and Green TR: Tape & Reel Package Temperature Range Part Number Marking ID Packing Type SOT-23-6 -40 to +85C AP3019AKTR-G1 GAS Tape & Reel TSOT-23-6 -40 to +85C AP3019AKTTR-G1 L8E Tape & Reel