AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS General Description Features • • • • • • • • • • • • • • The AP3156 is a low noise, constant frequency charge pump DC/DC converter that uses a tri-mode load switch (1X), fractional (1.5X), and doubling (2X) conversion to maximize efficiency for white LED applications. The AP3156 is capable of driving the LED channels at 120mA maximum from a 2.7V to 5.5V input. The current sinks may be operated individually or in parallel for driving higher-current LEDs. A low external parts count (two 1µF flying capacitors and two small 1µF capacitors at VIN and VOUT) make this part ideally suited for small, battery-powered applications. VIN Range: 2.7V to 5.5V Fully Programmable Current with Single Wire • 32-Step Logarithmic Scale • 20/25mA Max Current per Channel • Four Low Current Settings Down to 50µA • Low IQ (50µA) for Low Current Mode Tri-Mode 1X, 1.5X, and 2X Charge Pump for Maximum Efficiency and VF Coverage Drives up to Six Channels of LEDs Individual Main/Sub-Group Control No Inductors, Low Noise Operation 0.5/1/2MHz Constant Switching Frequency Small Application Circuit Built-In Thermal Protection Built-In Auto-Disable For Open Circuit Automatic Soft Start IQ <1µA in Shutdown Thermally-Enhanced QFN4040-16 Package: Available in “Green” Molding Compound (No Br, Sb) Lead Free Finish / RoHS Compliant (Note 1) AP3156 serial digital input is used to enable, disable and set current for each LED with a 32-level logarithmic scale plus four low-current settings down to 50µA for optimized efficiency, with a low quiescent current of only 50µA. Each output of the AP3156 is equipped with built-in protection for VOUT short circuit and auto-disable for LED failure conditions. Built-in soft-start circuitry prevents excessive inrush current during start-up. A low-current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1µA. The AP3156 is available in a lead-free, space-saving, thermally enhanced 16-pin 4x4mm QFN package. Applications • • • • Color (RGB) Lighting Programmable Current Sinks White LED Backlighting White Photo Flash for Digital Still Cameras Typical Application Circuit 10 VIN VIN C2P 1uF CIN 5 1uF C2 8 C2N 6 C1P C1N AP3156 VOUT 1uF C1 7 4 D6 LED SDI 2 SDI GND D5 LED D4 LED D3 LED D2 LED D1 LED 1uF COUT 1 D6 16 D5 15 D4 14 D3 13 D2 12 D1 9,11 AP3156 Rev. 1 1 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Ordering Information AP 3156 FV G - 7 Package FV : QFN4040-16 Device AP3156FVG-7 Notes: Package Code FV Lead Free G : Green Packing 7 : Tape & Reel 7” Tape and Reel Quantity Part Number Suffix 1500/Tape & Reel -7 Packaging (Note 2) QFN4040-16 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 2. 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. Pin Assignments D5 D4 D3 D2 15 14 13 8 4 C2N VOUT 7 3 C1N NC 11 GND Exposed Pad 6 2 C1P SDI 12 D1 5 1 C2P D6 16 (Top View) 10 VIN 9 GND QFN4040-16 AP3156 Rev. 1 2 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Pin Descriptions Pin Name D6 SDI NC VOUT C2P C1P C1N C2N GND VIN D1 D2 D3 D4 D5 GND Pin Description Number 1 Current Sink Input #6. Connected to VOUT when un-used. 2 Serial Digital Interface Control Pin 3 No Connection Charge pump output to drive load circuit. Requires 1µF capacitor connected between 4 this pin and ground Positive Terminal of Flying Capacitor 2. Connects a 1µF capacitor between C2P and 5 C2N. Positive terminal of Flying Capacitor 1. Connects a 1µF capacitor between C1P and 6 C1N. 7 Negative Terminal of Flying Capacitor 1 8 Negative Terminal of Flying Capacitor 2 9, 11 Ground. 10 Input Power Supply. Requires 1µF capacitor between this pin and ground. 12 Current sink input #1. Connected to VOUT when un-used. 13 Current sink input #2. Connected to VOUT when un-used. 14 Current sink input #3. Connected to VOUT when un-used. 15 Current sink input #4. Connected to VOUT when un-used. 16 Current sink input #5. Connected to VOUT when un-used. EP PAD Exposed Pad (bottom). Connected to GND directly underneath the package. Functional Block Diagram AP3156 Rev. 1 3 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Absolute Maximum Ratings Symbol ESD HBM ESD MM VIN VSDI IOUT TJ TLEAD Notes: (Note 3) Description Human Body Model ESD Protection Machine Model ESD Protection Input Voltage SDI to GND Voltage Maximum DC Output Current Operating Junction Temperature Range Maximum Soldering Temperature (at leads, 10 sec) Rating 2 200 -0.3 to 6 -0.3 to VIN +0.3 150 -40 to 150 300 Unit KV V V V mA °C °C Min 2.7 -40 Units V °C 3. Exceeding Absolute Maximum Ratings will cause permanent damage to the device. Recommended Operating Conditions Symbol VIN TA AP3156 Rev. 1 Parameter Input Voltage Operating Ambient Temperature 4 of 15 www.diodes.com Max 5.5 85 SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Electrical Characteristics CIN = COUT = C1 = C2 = 1.0µF; TA = 25°C, VIN = 3.5V. Unless otherwise noted. Symbol Parameter Test Conditions Min 1X Mode, 3.0≤VIN≤5.5, Active, No Load Current 1.5X Mode, 3.0≤VIN≤5.5, Active, IQ Quiescent Current No Load Current 2X Mode, 3.0≤VIN≤5.5, Active, No Load Current 50µA Setting, 1X Mode ISHDN Shutdown Current SDI = 0 18.6 ISET = 20mA (Note 5), TA = 25°C ISINK Current Accuracy IDX (Note 4) 3.6 ISET = 4mA (Note 5), TA = 25°C Current Matching Between Any VF: ID-Match Two Current Sink Inputs D1:D6 = 3.6V (Note 6) 1X to 1.5X or 1.5X to 2X ISET = 25mA VTH Transition Threshold at Any ISINK Pin Charge Pump Section TSS Soft-Start Time FCLK Clock Frequency Typ. Max 0.3 1 2.0 3 1.5 3 Unit mA 50 20 4 µA µA mA mA 1 21.4 4.4 0.5 % 150 mV 40 0.5/ 1/ 2 µs MHz SDI VSDI(L) VSDI(H) TSLO TSHI TOFF TSEP ISDI θJA Notes: SDI Threshold Low SDI Threshold High SDI Low Time SDI High Time SDI Off Timeout SDI Valid Sequence Timeout SDI Input Leakage Thermal Resistance Junction-to-Ambient VIN = 2.7V VIN = 5.5V 0.4 1.4 0.3 0.05 50 50 256 256 1 -1 QFN4040-16 (Note 7) V V µs µs µs µs µA 46 o C/W 4. Determined by the average current levels of all active channels 5. Sequence setting set to give nominal 20mA max output current and 4mA output current. 6. Defined as the deviation of any sink current from the average of all active current channels 7. Device mounted on FR-4 substrate, 2"*2", 2oz, copper, double-sided PC board, AP3156 Rev. 1 5 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Typical Performance Characteristics Efficiency vs. Supply Voltage Turn-On to 1X Mode (VIN = 4.2V; 20mA Load) VF=3.3V VF=2.8V VF=3.0V AP3156 Rev. 1 Turn-On from 1.5X Mode (VIN = 3.5V; 20mA Load) Turn-On to 2X Mode (VIN = 2.7V; 20mA Load) Turn-Off from 1.5X Mode (VIN = 3.5V; 20mA Load) Current Matching vs. Temperature 6 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Typical Performance Characteristics (Continued) Load Characteristics (VIN = 3.2V; 1.5X Mode; 10mA Load) Load Characteristics (VIN = 2.7V; 2X Mode; 20mA Load) Load Characteristics (VIN = 3.5V; 1.5X Mode; 20mA Load) Load Characteristics (VIN = 3.1V; 2X Mode; 25mA Load) Load Characteristics (VIN = 3.5V; 1.5X Mode; 25mA Load) AP3156 Rev. 1 7 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Typical Performance Characteristics (Continued) SDI Threshold High vs. Input Voltage AP3156 Rev. 1 8 of 15 www.diodes.com SDI Threshold Low vs. Input Voltage SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Functional Description The AP3156 is a tri-mode high efficiency six-channel charge pump (1x, 1.5x or 2x) device intended for white LED backlight applications. An internal comparator circuit compares the voltage at each constant current sink input against a reference voltage. To ensure maximum power efficiency, the most appropriate switching mode (1x, 1.5x, 2x) is automatically selected. 20 21 22 23 24 25 26 27 28 29 30 31 32 The AP3156 requires only four external components: two 1µF ceramic flying capacitors (C1 and C2) for the charge pump, one 1µF ceramic input capacitor (CIN), and one 1µF ceramic charge pump output capacitor (COUT). The each output channel of the AP3156 can drive six individual LEDs with a maximum current of 25mA per channel. These can be paralleled to give a total output current of 150mA. Constant Current Output Level Settings The constant current level for the outputs is set via the Serial Digital Interface and has a logarithmic variance. This results in the LED brightness varying linearly when the settings in the scale are traversed. Because the inputs D1 to D6 are true independent constant current sinks, the voltage observed on any single given input will be determined by the difference between VOUT and the actual forward voltage (VF) of the LED being driven. Since the constant current levels for the AP3156 are programmable, no PWM (pulse width modulation) or additional control circuitry is needed to control LED brightness. With its high-speed serial interface (>1MHz data rate), the LED current drive of the AP3156 can be changed successively to brighten or dim LEDs in smooth transitions or in abrupt steps, giving the user complete programmability and real-time control of LED brightness. There are 32 current level settings separated from one another by approximately 0.5dB (see Constant Current Programming Level table). Code 1 is full-scale current, and Code 31 is full scale attenuated roughly 15dB. Code 32 is reserved as a “no current” setting. Constant Current Programming Levels (mA) 20mA Max 25mA Max Data IOUT (mA) IOUT (mA) 1 20 25 2 18.9 23.6 3 17.8 22.3 4 16.8 21.0 5 15.9 19.9 6 15.0 18.7 7 14.2 17.7 8 13.4 16.7 9 12.6 15.8 10 11.9 14.9 11 11.2 14.1 12 10.6 13.3 13 10.0 12.5 14 9.5 11.8 15 8.9 11.2 16 8.4 10.5 17 8.0 10.0 18 7.5 9.4 19 7.1 8.9 AP3156 Rev. 1 6.7 6.3 6.0 5.6 5.3 5.0 4.7 4.5 4.2 4.0 3.8 3.6 0 8.4 7.9 7.5 7.0 6.7 6.3 5.9 5.6 5.3 5.0 4.7 4.4 0 Low Current Output Level Setting The AP3156 has a distinct Low Current mode with ultra-low quiescent current. For drive currents of 2mA or less, the device operates with significantly reduced quiescent current. Low Current Programming Levels (mA) Data Current (mA) 1 2 2 1 3 0.5 4 0.05 5 0 Serial Digital Interface SDI is a general purpose 1-wire digital interface designed to transport digital controls for power management ICs such as AP3156. The current levels of the six channels can be configured either together, individually or specific grouping. Up to 32 current levels are allowed. A generic system controller can easily support the SDI protocol via bit-banging over its general purpose I/Os. The SDI protocol is simple yet flexible enough to accommodate different switching clock frequencies. Any sequence of negative-edged pulses of 63 or less (see Instruction & Data Table) separated by TSEP at the SDI pin is interpreted by the AP3156 as a channel configuration event. In future, the number of pulses can be extended to support additional commands. 9 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Functional Description Instruction & Data Table First Second Sequence Sequence 1~3 - (Continued) Description No Action Disabled Current Sinks Unused current channels must be disabled by connecting the sinks to VOUT with only a small sense current flowing through the disabled channel. 4~7 1~32 8 1 Reserved Switching frequency selected to 0.5MHz 2 Switching frequency selected to 1MHz (default) 3 Switching frequency selected to 2MHz Short-Circuit Protection Short-circuit protection function is incorporated to prevent excessive load current when either flying cap terminals or output pin electrically tied to a very lower voltage or ground. 4~32 1 Reserved 20mA Constant Current Mode, 32 current level supported (default) Over-Voltage Protection Over-Voltage Protection function is incorporated to limit the output voltage under a safe value to avoid on-chip device breakdown. 2 Low Current Mode, 4 current level supported Under-Voltage Lockout Under-Voltage lockout feature disables the device when the input voltage drops below UVLO threshold. 3 25mA Constant Current Mode, 32 current level supported 4~32 Reserved Set current level for all 6 Channels Set current level for CH1, CH2, CH3 Set current level for CH4, CH5, CH6 Set current level for CH1, CH2, CH3, CH4 Set current level for CH5, CH6 9 10 1~32* 11 1~32* 12 1~32* 13 1~32* 14 1~32* 15 1~32* 16 1~32* Set current level for CH1, CH2, CH3, CH4, CH5 Set current level for CH6 17 1~32* Set current level for CH5 18 1~32* Set current level for CH4 19 1~32* Set current level for CH3 20 1~32* Set current level for CH2 21 1~32* Set current level for CH1 22~32 - Reserved 33 - 34 - Soft Reset 1) 1MHz switching frequency 2) 20mA Constant Current Mode 3) All Channels in Current Level Setting 32 (0mA) Null Sequence 35~63 Soft-Start Soft-start is incorporated to prevent excessive inrush current during power-up, mode switching, and transitioning out of stand-by mode. Thermal Auto Shutdown When the die temperature exceeds the thermal limit, the device will be disabled and enter stand-by mode. The operation resumes whenever the die cools off sufficiently. Switching frequency By default, the AP3156 is working at 1MHz switching frequency. It can also work at 0.5MHz or 2MHz switching frequency which can be set through the Serial Digital Interface. An user can choose the appropriate switching frequency with consideration of noise immunity, input and output voltage ripple requirement, and capacitor selection. Reserved * Only 1~5 are valid current settings at Low Current Mode. AP3156 Rev. 1 10 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Serial Digital Interface SDI Command Timing Protocol For the SDI command to be successfully received by the AP3156, all SDI timing specifications must be satisfied. When no command is being sent, the SDI pin should be held High. If the SDI pin goes Low and stays Low for a time length between TSLO(min) and TSLO(max) and then goes High and stays High for the length between TSHI(min) and TSHI(max), one falling edge is registered by the AP3156. The total number of falling edges registered before the SDI pin is held High for longer than the maximum separation time TSEP(max) identifies the command that has been received by the AP3156. The next series of falling edges before another separation time of TSEP represents the next command. In other words, the AP3156 counts the number of consecutive falling edges on the SDI pin and a different number represents a different command. Each command is executed after it is successfully received. If at any time the SDI pin is held Low for longer than the maximum chip disable time TOFF(max), then the AP3156 will be turned off and enters the shutdown mode. Setting the SDI pin switching from Low to High will re-enable the AP3156 and leave the shutdown mode. If the SDI pin is held on for a time duration over TSEP, then an end of a sequence (EOS) occurs with a number of pulse conformed to specified timing. A valid dual-sequence command occurs when one valid sequence is defined as an instruction, and the other is defined as data. Both sequences have number of pulses less than 33. Also, a valid single-sequence command occurs when the sequence has number of pulses greater than 32. First Sequence TSHI SDI 1 2 8 Second Sequence TSLO 9 Channel Selection TSEP TSEP 10 1 2 Current Setting Channel D1 Channel 1 in dimming control Set Channel 1 to current level 2. Channel D2 Channel 2 in dimming control Set Channel 2 to current level 2. Channel D3 Channel 3 in dimming control Set Channel 3 to current level 2. Channel D4 Channel 4 in dimming control Set Channel 4 to current level 2. Channel D5 Channel 5 in dimming control Set Channel 5 to current level 2. Channel D6 Channel 6 in dimming control Set Channel 6 to current level 2. Figure 1: Dimming Control Selection (Dual-Sequence Command) AP3156 Rev. 1 11 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Serial Digital Interface (Continued) Second Sequence First Sequence TSHI TSLO TSEP TSEP SDI 1 2 7 8 1 9 Current Mode Selection 2 Select Low Current Mode Figure 2: Current Mode Selection (Dual-Sequence Command) First Sequence TSHI Second Sequence TSLO TSEP TSEP SDI 1 2 6 7 8 1 Switching Frequency Selection 2 Select Switching Frequency to 1 MHZ Figure 3: Switching Frequency Selection (Dual-Sequence Command) First Sequence TSHI TSLO TSEP SDI 1 2 31 32 33 Soft Reset Figure 4: Soft Reset (Single-Sequence Command) AP3156 Rev. 1 12 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Marking Information (1) QFN4040-16 ( Top View ) XX : F7 : AP3156 Y : Year : 0~9 W : Week : A~Z : 1~26 week; a~z : 27~52 week; z represents 52 and 53 week X : A~Z : Green XX YW X Part Number AP3156FVG-7 Package Information Package QFN4040-16 Identification Code F7 (All Dimensions in mm) (1) Package Type: QFN4040-16 CL 0.10 C Seating Plane B C 0.15Max. 0.25 A Side View Land Pattern Recommendatrion 4 3.7 2X- 0.55/0.65 0.08 C 0.05Max. 16X- 3.90/4.10 A 10 4 1 3.7 0.55/0.65 4 2.3/2.5 3.90/4.10 2.3/2.5 (Pin #1 ID) (Pin #1 ID) 16 0.25 B 0.65Typ. 0.28/0.38 0.10 C A B Bottom View AP3156 Rev. 1 16x-1.0 2X- 13 of 15 www.diodes.com 12x-0.65 Bottom View SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS Taping Orientation Note: (Note 8) 8. The taping orientation of the other package type can be found on our website at http://www.diodes.com/datasheets/ap02007.pdf AP3156 Rev. 1 14 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated AP3156 HIGH EFFICIENCY 1X/1.5X/2X CHARGE PUMP FOR WHITE LED APPLICATIONS 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 reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to this document and any product described herein. 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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 devices 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 systems-related information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated 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 © 2009, Diodes Incorporated www.diodes.com AP3156 Rev. 1 15 of 15 www.diodes.com SEPTEMBER 2009 © Diodes Incorporated