AP3154

AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Features • • • • • • • • • • • • • • • • • Up to 88% Max power efficiency Wide input voltage range: 2.7V ~ 5.5V 1x, 1.5x, and 2x charge-pump modes Drive up to 4 white LEDs Default maximum current setting: 30mA each channel 120mA maximum output current through 4 channels Programmable switching frequency, default 1.2MHz Spread Spectrum Control with 10% frequency deviation 1-wire Serial Digital Interface (SDI) or PWM for dimming control Soft-start during power-up and mode switching Soft-stop during shutdown Short-circuit protection Over-voltage protection and under-voltage lockout Low shutdown current < 6µA Industry-leading low profile package DFN3030-12: Available in “Green” Molding Compound (No Br, Sb) Lead Free Finish / RoHS Compliant (Note 1) General Description The AP3154 is a high efficiency charge-pump white LED driver with 1x, 1.5x, 2x operating modes. The AP3154 operates on power supplies from 2.7v to 5.5v. It drives up to four channels of white LEDs while the intensity of each channel is configured by varying the respective current levels. Each channel can supply up to 30mA current. Up to four channels can be ganged together to provide maximum load current of 120mA. The Serial Digital Interface (SDI) provides the capability to configure the current for each LED channel. Some other key features, such as Up Spread Spectrum Control, different charge-pump switching frequencies (0.6MHz/1.2MHz/1.8MHz), and PWM dimming control, can also be programmed through the interface. The AP3154 has a built-in soft-start circuit to minimize the inrush current during power-up and mode switching. Various protections such as short-circuit, over-voltage, under-voltage, and thermal shutdown are integrated to ensure system reliability. The quiescent current of AP3154 during shutdown is less than 6µA. Applications • • • • • • Mobile Phone PDA (Personal Digital Assistant) White LED Backlighting Camera Flash LED Lighting LCD Modules Portable Devices Ordering Information AP 3154 F G - 7 Package F : DFN3030-12 Device AP3154FG-7 Notes: Green G : Green Packing 7 : Tape & Reel Package Code F Packaging (Note 2) DFN3030-12 7” Tape and Reel Quantity Part Number Suffix 3000/Tape & Reel -7 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 AP3154 Rev. 2 1 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Pin Assignment ( Top View ) D4 SDI C1P C1N VOUT C2P 1 2 3 4 5 6 12 11 D3 D2 D1 GND VIN C2N Exposed Pad 10 9 8 7 DFN3030-12 Pin Descriptions Pin Name D4 SDI C1P C1N VOUT C2P C2N VIN GND D1 D2 D3 GND Pin # 1 2 3 4 5 6 7 8 9 10 11 12 EP PAD Description Current Sink Input #4. Connect to VOUT when un-used. 1-wire Serial Digital Interface Input / PWM input Positive Terminal of Flying Capacitor. Connect a 1µF capacitor between C1P and C1N. Negative Terminal of Flying Capacitor. The charge pump output voltage to drive load circuit. Connect a 1µF capacitor between this pin and ground. Positive Terminal of Flying Capacitor. Connect a 1µF capacitor between C2P and C2N. Negative Terminal of Flying Capacitor. Input Power Source. Connect a 1µF capacitor between this pin and ground. Ground. Current Sink Input #1. Connect to VOUT when un-used. Current Sink Input #2. Connect to VOUT when un-used. Current Sink Input #3. Connect to VOUT when un-used. Exposed Pad (bottom). Connect to ground underneath the package. AP3154 Rev. 2 2 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Block Diagram C2P C2N C1P C1N VOUT VIN CHARGE PUMP SWITCHES SHORT CIRCUIT PROTECTION OVER VOLTAGE PROTECTION SDI SERIAL DIGITAL INTERFACE DIGITAL CONTROL BLOCK OUTPUT VOLTAGE REGULATION & LED SHORT CIRCUIT DETECTION BANDGAP OSCILLATOR D1 D2 D3 OVER TEMPERATURE PROTECTION UNDER VOLTAGE LOCKOUT CURRENT CONTROL D4 GND Typical Application Circuit VIN 1uF CIN 8 VIN C2P 6 1uF C2 1uF C1 7 C2N 3 C1P C1N AP3154 4 VOUT 5 D4 LED D3 LED D2 LED D1 LED 1uF COUT SDI 2 SDI GND 9 D4 D3 D2 D1 1 12 11 10 AP3154 Rev. 2 3 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Absolute Maximum Ratings Symbol ESD HBM ESD MM (Notes 3) Description Human Body Model ESD Protection Machine Model ESD Protection Input Voltage SDI to GND Voltage Maximum DC Output Current Maximum Power Dissipation Operating Junction Temperature Range Value 2 200 -0.3 to 6 -0.3 to VIN + 0.3 150 0.85 -40 to 150 Units KV V V V mA W °C VIN VSDI IOUT PD TJ Notes: 3. Exceeding Absolute Maximum Ratings will cause permanent damage to the device. Recommended Operating Conditions Symbol VIN TA Input Voltage Operating Ambient Temperature Parameter Min 2.7 -40 Max 5.5 85 Units V °C AP3154 Rev. 2 4 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Electrical Characteristics CIN = COUT = C1 = C2 = 1.0µF; TA = 25°C, VIN = 3.5V. Unless otherwise stated. Symbol Description Conditions Min Typ. 1X Mode IQ Quiescent Current Fosc=1.2MHz, 1.2 SDI=HIGH, no load ISHDN Shutdown Current SDI = 0 0.3 ISINK Current Accuracy ISINK = 20mA IDX -10 (Note 4) Current Matching VF: D1=D2=D3=D4 ID-Match ID = 2, 20mA (Note 5) TSS Soft-start Time 1 FCLK Switching Clock Frequency 0.6/1.2/1.8 FSSP Spread Spectrum Enabled +10 VSDI(L) SDI Threshold Low VIN = 2.7V to 5.5V VSDI(H) SDI Threshold High VIN = 2.7V to 5.5V 1.6 TSLO SDI Low Time 0.05 TSHI SDI High Time 0.05 PWM Frequency (Range 1) 0.2 fPWM PWM Frequency (Range 2) 20 TPWM PWM Signal Period 1/ fPWM-Max TPLO PWM Signal Low (LED off) 1 TPHI PWM Signal High (LED on) 1 PWM 65 TOFF Chip Disable (held low) No PWM 512 PWM 65 Interval between SDI TSEP sequences (held high) No PWM 512 ISDI SDI Input Leakage -1 VOUT Short to GND hold ISCP 500 Current Thermal Resistance1 – DFN3030-12 θJA 160 Junction to Ambient (Note 6) Maximum Thermal DFN3030-12 θJC Resistance1 – 21 (Note 6) Junction to Case Notes: 4. Determined by the average current levels of all active channels. 5. Defined as the deviation of any sink current from the average of all active current channels. 6. Device mounted on FR-4 substrate PC board, 2oz copper, with minimum recommended pad layout. Max Units mA 6 10 5 µA % % ms MHz % V V µs µs KHz KHz µs µs µs ms µs ms µs µA mA °C/W °C/W 0.4 50 50 1.5 30 1/ fPWM-Min TPWM – 1 TPWM – 1 100 800 100 800 1 AP3154 Rev. 2 5 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Typical Performance Characteristics Efficiency vs. Supply Voltage Turn-On to 1X Mode (VIN = 4.2V; 20mA Load) 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 AP3154 Rev. 2 6 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Typical Performance Characteristics Load Characteristics (VIN = 3.5V; 1.5X Mode; 14mA Load) (Continued) Load Characteristics (VIN = 2.7V; 2X Mode; 14mA Load) Load Characteristics (VIN = 3.5V; 1.5X Mode; 20mA Load) Load Characteristics (VIN = 2.7V; 2X Mode; 20mA Load) Load Characteristics (VIN = 3.5V; 1.5X Mode; 30mA Load) Load Characteristics (VIN = 3.1V; 2X Mode; 30mA Load) AP3154 Rev. 2 7 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Typical Performance Characteristics Enable Threshold High vs. Input Voltage (Continued) Enable Threshold Low vs. Input Voltage PWM Dimming Operation (VIN = 3.5V; 20mA Load; Duty=1:1; f=1KHz) PWM Dimming Operation (VIN = 3.5V; 20mA Load; Duty=11:1; f=1KHz) PWM Dimming Operation (VIN = 3.5V; 20mA Load; Duty=1:11; f=1KHz) AP3154 Rev. 2 8 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Functional Description General Functional Description The AP3154 is designed for white LED 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 (x1, x1.5, x2) is automatically selected. In applications, only four external components are required: two 1µF ceramic flying capacitors (C1 and C2), one 1µF ceramic capacitor each for input and output (CIN, COUT). AP3154 drives up to four white LEDs with a maximum current of 30mA each. A total of 120mA is provided to the four channels. Through SDI, the current into each channel can be configured in accordance to specific protocol and pre-defined values. Maximum output current can be set to one of the four possible scales: 2mA, 14mA, 20mA, 30mA. Among these, the ‘2mA’ setting is called “low current mode”. This would be useful for applications which require very low operating current, e.g. transmissive LCD panels. For each maximum output current scale, there are 16 current level settings separated from one another by approximately 1dB. While level-16 corresponds to maximum current output, level-1 corresponds to zero output current. As the current level varies logarithmically, intensity of the LED changes in a linear fashion. The current level at the individual channels is configured via SDI which supports data rate up to 10MHz. It allows the main controller in the system to be offloaded to perform more mission-critical functions. Serial Digital Interface SDI is a general purpose 1-wire digital interface designed to transport digital controls for power management ICs such as AP3154. The current levels of the four channels can be configured either together or individually. Up to 16 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 table 1), separated by TSEP at the SDI pin is interpreted by AP3154 as a channel configuration event. In the future, the number of pulses can be extended to support additional commands. In addition to the SDI protocol, dimming control can also be achieved by presenting a timing-specific PWM signaling at the SDI pin. Number of Falling Edges 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21~62 63 All 4 Channels in dimming control CH2, CH3 and CH4 in dimming control CH1 and CH2 in dimming control CH3 and CH4 in dimming control CH1 in dimming control CH2 in dimming control CH3 in dimming control CH4 in dimming control Low-Current Mode (Maximum Current set to 2mA) Maximum Current set to 14mA (All channels) Maximum Current set to 20mA (All channels) Maximum Current set to 30mA (All channels) 10% Up Spread Spectrum Control Enable/Disable Switching Frequency set to 0.6Mhz Switching Frequency set to 1.2Mhz Switching Frequency set to 1.8Mhz Reserved PWM Dimming Control Enable/Disable Dimming Control Current Level Setting AP3154 supports four maximum output current scales including 30mA, 20mA, 14mA, and 2mA low-current scales. For each maximum current scale, there are 16 current level settings separated from one another by appromimately 1dB (see table 2). By default, maximum current scale is set to 20mA and dimming control current level is set to maximum (level 16). Through SDI, certain channels or all four channels can be selected, and dimming control level for these channels can be set to maximum (level 16), minimum (level1), up from minimum to maximum or down from maximum to minimum (see table 1). Dimming Control Current Levels 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Iout (20mA) Iout (30mA) Iout (14mA) Low-Current (2mA) 2.0 1.78 1.59 1.43 1.27 1.11 1.02 0.89 0.79 0.70 0.63 0.57 0.51 0.44 0.41 0.05 Command Description Current level step up (1 up to level 16) Current level step down (16 down to level 1) Current level set to 16 (maximum current level) Current level set to 1 (minimum current level) 20.0 30.0 14.0 17.8 26.7 12.5 15.9 23.8 11.1 14.3 21.4 10.0 12.7 19.0 8.9 11.1 16.7 7.8 10.2 15.2 7.1 8.9 13.3 6.2 7.9 11.9 5.6 7.0 10.5 4.9 6.3 9.5 4.4 5.7 8.6 4.0 5.1 7.6 3.5 4.4 6.7 3.1 4.1 6.2 2.9 0.05 0.05 0.05 Table 2: Dimming Control Current Level AP3154 Rev. 2 9 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Functional Description (Continued) 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. Soft-Start and Soft-Stop Soft-start and Soft-stop function are incorporated to prevent excessive inrush current during power-up, mode switching, power-down, transition out of stand-by mode. 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 low voltage or ground. Over-Voltage Protection Over-voltage protection function is incorporated to limit the output voltage under a safe value to avoid on-chip device breakdown. Under-Voltage Lockout Under-voltage lockout feature disables the device when the input voltage drops below UVLO threshold. Thermal Shutdown When the die temperature exceeds the thermal limit, the device will be disabled and enter stand-by mode. The operation will be resumed whenever the die cools off sufficiently. Switching Frequency By default, AP3154 is working at 1.2Mhz switching frequency. It can also work at 0.6MHz or 1.8MHz switching frequency set through SDI. User can choose the appropriate switching frequency with consideration of noise immunity, input/output voltage ripple requirement, and capacitor selection etc. Up Spread Spectrum Control When this feature is enabled through SDI, the switching frequency periodically varies between 100% and 110% of nominal frequency. It flattens the peak energy on nominal frequency over a range of frequency band so that EMI effect is significantly reduced. PWM Dimming Control The AP3154 provides flexible dimming control with either 16-level SDI protocol control or PWM dimming control through SDI pin. When PWM dimming control is enabled, the sink current is adjusted by the duty cycle of the signal applied on SDI pin. Serial Digital Interface SDI Command Timing For an SDI command to be successfully received by the AP3154, all SDI timing specifications should 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 of between TSLO(min) and TSLO(max) and then goes high and stays high for between TSHI(min) and TSHI(max), one falling edge is registered by the AP3154. 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 AP3154. The next series of falling edges before another separation time TSEP represents the next command. In other words, the AP3154 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), the AP3154 is disabled and enters the shutdown mode. All internal registers are reset to default. Setting the SDI pin high again will re-enable the AP3154 and bring it out of the shutdown mode. The AP3154 enters the SDI mode by default when it is first powered up. The first SDI command 63 (63 falling edges) will put the AP3154 into the PWM mode, where a high level on the SDI pin turns the LEDs on, a low level turns the LEDs off and the duty cycle determines the average LED brightness. The next SDI command 63 will put the AP3154 back into the SDI mode. It should be pointed out that the PWM mode is for dimming control only and configuration settings have to be done in the SDI mode. Channel Configuration Example The following timing diagram is a dimming control example. In this example, the first command (command 10) selects Channel 2 as the configuration target and the second command (command 2) sets the Channel 2 current level to one step lower while the other channels remain unchanged. AP3154 Rev. 2 10 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Serial Digital Interface (Continued) Marking Information (1) DFN3030-12 ( Top View ) XX YWX 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 X : A~Z : Green Package DFN3030-12 Identification Code F8 Part Number AP3154F AP3154 Rev. 2 11 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Package Information (1) Package type: DFN3030-12 (All Dimensions in mm) 0.15max. 2.9 / 3.1 2.3 / 2.5 A 0.10 C 0.08 C 0.25 A 0.57/0.63 Seating plane C 0/0.05 B 2.9 / 3.1 1.5 / 1.7 2x R0. 3 2x- 0.25 B 0.45typ 0.18/0.28 Bottom View 0.10 M C A B AP3154 Rev. 2 12 of 13 www.diodes.com 0.25/0.55 FEBRUARY 2009 © Diodes Incorporated AP3154 120mA HIGH EFFICIENCY WHITE LED DRIVER Taping Orientation Notes: 7. The taping orientation of the other package type can be found on our website at http://www.diodes.com/datasheets/ap02007.pdf IMPORTANT NOTICE Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to any product herein. Diodes Incorporated does not assume any liability arising out of the application or use of any product described herein; neither does it convey any license under its patent rights, nor the rights of others. The user of products 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 our website, harmless against all damages. LIFE SUPPORT Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written approval of the President of Diodes Incorporated. AP3154 Rev. 2 13 of 13 www.diodes.com FEBRUARY 2009 © Diodes Incorporated