LP5526 Lighting Management Unit with High Voltage Boost Converter with up to 150mA Serial FLASH LED Driver General Description Features LP5526 is a Lighting Management Unit for portable applications. It is used to drive display backlights, keypad LEDs, RGB LEDs and camera flash LEDs. LP5526 can drive 2 separately connected strings of LEDs with high voltage boost converter. The RGB driver allows driving either individual color LEDs or RGB LED from separate supply power, or it can be used to drive series connecter flash LEDs from high voltage boost converter. The backlight drivers (MAIN and SUB pins) are both high resolution constant current mode drivers. The flash outputs can drive series connected flash LED with up to 150mA of current. External PWM control can be used for dimming any selected LED outputs or it can be used to trigger the flash. The flash has also 1-second safety timer. The device is controlled through 2-wire low voltage I2C compatible interface that reduces the number of required connections. n High efficiency boost converter with programmable output voltage up to 20V n 2 individual drivers for serial display backlight LEDs n Automatic dimming controller n Stand alone RGB controller n Dedicated flash function n Safety function to avoid prolonged flash n 3 general purpose IO pins n 25-bump micro SMD Package: (2.54mm x 2.54mm x 0.6mm) Applications n Cellular Phones and PDAs n MP3 Players n Digital Cameras Typical Application 20179770 © 2006 National Semiconductor Corporation DS201797 www.national.com LP5526 Lighting Management Unit with High Voltage Boost Converter with up to 150mA Serial FLASH LED Driver March 2006 LP5526 Typical Application (Continued) 20179701 Connection Diagrams 25-Bump Thin Micro SMD Package, Large Bump NS Package Number TLA25CCA 20179772 20179771 Bottom View Top View www.national.com 2 LP5526 Pin Descriptions Pin # Name Type Description 5E SW Output 5D FB Input Boost Converter Power Switch 5C RLED Output Red LED Output (Current Sink / Open Drain Switch) 5B GLED Output Green LED Output (Current Sink / Open Drain Switch) Boost Converter Feedback 5A BLED Output Blue LED Output (Current Sink / Open Drain Switch) 4E GND_SW Ground Power Switch Ground 4D NRST Input 4C SCL Logic Input External Reset, Active Low Clock Input for I2C Compatible Interface 4B IRGB Input 4A GND_RGB Ground Ground for RGB LED Currents External RGB LED Maximum Current Set Resistor 3E VDD2 Power Supply Voltage 3.0...5.5 V 3D VDDIO Power 3C SDA Logic Input/Output Data Input/Output for I2C Compatible Interface 3B GPIO[2] Logic Input/Output General Purpose Logic Input/Output 3A GPIO[0] / PWM Logic Input/Output General Purpose Logic Input/Output / External PWM Input 2E GND_WLED Ground Ground for White LED Currents (MAIN and SUB Outputs) 2D GNDT Ground Ground Supply Voltage for Digital Input/Output Buffers and Drivers 2C VDD1 Power Supply Voltage 3.0...5.5 V 2B VREF Output Reference Voltage (1.23V) 2A GPIO[1] Logic Input/Output 1E MAIN Output MAIN Display White LED Current Output (Current Sink) 1D SUB Output SUB Display White LED Current Output (Current Sink) 1C VDDA Output Internal LDO Output (2.80V) 1B GND Ground Ground for Core Circuitry 1A IRT Input General Purpose Logic Input/Output Oscillator Frequency Set Resistor Package Mark 20179796 Ordering Information Order Number Package Marking Supplied As Spec/Flow LP5526TL LP5526TLX 5526 TNR 250 NoPb 5526 TNR 3000 NoPb 3 www.national.com LP5526 Absolute Maximum Ratings Operating Ratings (Notes 1, 2) (Notes 1, 2) V (SW, FB, MAIN, SUB) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VDD1,2 3.0 to 5.5V VDDIO 1.65V to VDD1 V (SW, FB, MAIN, SUB, RLED, GLED, BLED) -0.3V to +23V Recommended Load Current (RLED, GLED, BLED) CC Mode VDD1, VDD2, VDDIO, VDDA -0.3V to +6.0V Recommended Total Boost Converter Load Current Voltage on IRGB, IRT, VREF Voltage on Logic Pins I (VREF) I(RLED, GLED, BLED) -0.3V to VDD1+0.3V with 6.0V max -0.3V to VDDIO +0.3V with 6.0V max 10µA Internally Limited Junction Temperature (TJ-MAX) 125oC Storage Temperature Range -65oC to +150oC Maximum Lead Temperature (Soldering) (Note 4) 260oC Machine Model: www.national.com 0mA to 150mA Junction Temperature (TJ) Range -30oC to +125oC Ambient Temperature (TA) Range (Note 6) -30oC to +85oC Junction-to-Ambient Thermal Resistance(θJA), TLA25 Package (Note 7) ESD Rating (Note 5) Human Body Model: 0mA to 50mA/driver Thermal Properties 100mA Continuous Power Dissipation (Note 3) 0 to +21V 2kV 200V 4 60 - 100oC/W Limits in standard typeface are for TJ = 25o C. Limits in boldface type apply over the operating ambient temperature range (-30oC < TA < +85oC). Unless otherwise noted, specifications apply to the LP5526 Block Diagram with: VDD1,2 = 3.0 ... 5.5V, CVDD = CVDDIO = 100nF, COUT = 2 x 4.7µF, CIN = 10µF, CVDDA = 1µF, CVREF = 100nF, L1 = 10µH, RRGB = 2.4kΩ and RRT = 82kΩ (Note 9). Symbol IVDD VDDA Typ Max Units Standby supply current (VDD1, VDD2) Parameter NSTBY = L Register 0DH=08H (Note 10) Condition Min 1.7 7 µA No-boost supply current (VDD1, VDD2) NSTBY = H, EN_BOOST = L 300 800 µA No-load supply current (VDD1, VDD2) NSTBY = H, EN_BOOST = H Autoload OFF 780 1300 uA Output voltage of internal LDO IVDDA = 1mA +3 % 2.80 -3 VREF Reference voltage (Note 11) 1.23 V V Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Operating Ratings are conditions under which operation of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical Characteristics tables. Note 2: All voltages are with respect to the potential at the GND pins. Note 3: Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at TJ=150oC (typ.) and disengages at TJ=130oC (typ.). Note 4: For detailed soldering specifications and information, please refer to National Semiconductor Application Note AN1112 : Micro SMD Wafer Level Chip Scale Package Note 5: The Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged directly into each pin. MIL-STD-883 3015.7 Note 6: In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may have to be derated. Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-OP = 125oC), the maximum power dissipation of the device in the application (PD-MAX), and the junction-to ambient thermal resistance of the part/package in the application (θJA), as given by the following equation: TA-MAX = TJ-MAX-OP – (θJA x PD-MAX). Note 7: Junction-to-ambient thermal resistance is highly application and board-layout dependent. In applications where high maximum power dissipation exists, special care must be paid to thermal dissipation issues in board design. Note 8: Min and Max limits are guaranteed by design, test, or statistical analysis. Typical numbers are not guaranteed, but do represent the most likely norm. Note 9: Low-ESR Surface-Mount Ceramic Capacitors (MLCCs) used in setting electrical characteristics. Note 10: Boost output voltage set to 8V (08H in register 0DH) to prevent any unneccessary current consumption. Note 11: No external loading allowed for VREF pin. 5 www.national.com LP5526 Electrical Characteristics (Notes 2, 8) LP5526 Block Diagram 20179774 www.national.com 6 RESET: In the RESET mode all the internal registers are reset to the default values. Reset is entered always if input NRST is LOW or internal Power On Reset is active. Power On Reset (POR) will activate during the chip startup or when the supply voltages VDD1 and VDD2 fall below 1.5V. Once VDD1 and VDD2 rises above 1.5V, POR will inactivate and the chip will continue to the STANDBY mode. NSTBY control bit is low after POR by default. STANDBY: The STANDBY mode is entered if the register bit NSTBY is LOW and Reset is not active. This is the low power consumption mode, when all circuit functions are disabled. Registers can be written in this mode and the control bits are effective immediately after start up. STARTUP: When NSTBY bit is written high, the INTERNAL STARTUP SEQUENCE powers up all the needed internal blocks (VREF, Bias, Oscillator etc.). To ensure the correct oscillator initialization, a 10ms delay is generated by the internal state-machine. If the chip temperature rises too high, the Thermal Shutdown (TSD) disables the chip operation and STARTUP mode is entered until no thermal shutdown event is present. BOOST STARTUP: Soft start for boost output is generated in the BOOST STARTUP mode. The boost output is raised in low current PWM mode during the 20ms delay generated by the state-machine. All LED outputs are off during the 20ms delay to ensure smooth startup. The Boost startup is entered from Internal Startup Sequence if EN_BOOST is HIGH or from Normal mode when EN_BOOST is written HIGH. NORMAL: During NORMAL mode the user controls the chip using the Control Registers. The registers can be written in any sequence and any number of bits can be altered in a register in one write. 20179775 7 www.national.com LP5526 Modes of Operation LP5526 excess charge from the output capacitor at very light loads. Active load can be disabled by writing the EN_AUTOLOAD bit low. Disabling active load will increase slightly the efficiency at light loads, but the downside is that pulse skipping will occur. The Boost Converter should be stopped and set to 8V when there is no load to minimize the current consumption. The topology of the magnetic boost converter is called CPM control, current programmed mode, where the inductor current is measured and controlled with the feedback. The user can program the output voltage of the boost converter. The output voltage control changes the resistor divider in the feedback loop. The following figure shows the boost topology with the protection circuitry. Four different protection schemes are implemented: Power-Up Sequence When powering up the device, VDD1 and VDD2 should be greater than VDDIO to prevent any damage to the device. 20179776 Magnetic Boost DC/DC Converter The LP5526 Boost DC/DC Converter generates an 8…20V supply voltage for the LEDs from single Li-Ion battery (3V…4.5V). The output voltage is controlled with an 8-bit register in 12 steps. The converter is a magnetic switching PWM mode DC/DC converter with a current limit. Switching frequency is 1MHz, when timing resistor RT is 82kΩ. Timing resistor defines the internal oscillator frequency and thus directly affects boost frequency and RGB timings. EMI filter (RSW and CSW) on the SW pin can be used to suppress EMI caused by fast switching. These components should be as near as possible to the SW pin to ensure reliable operation. The LP5526 Boost Converter uses pulseskipping elimination to stabilize the noise spectrum. Even with light load or no load a minimum length current pulse is fed to the inductor. An active load is used to remove the 1. Over voltage protection, limits the maximum output voltage — Keeps the output below breakdown voltage. — Prevents boost operation if battery voltage is much higher than desired output. 2. Over current protection, limits the maximum inductor current — Voltage over switching NMOS is monitored; too high voltages turn the switch off. 3. Feedback break protection. Prevents uncontrolled operation if FB pin gets disconnected. 4. Duty cycle limiting, done with digital control. 20179777 Boost Converter Topology www.national.com 8 LP5526 Magnetic Boost DC/DC Converter (Continued) MAGNETIC BOOST DC/DC CONVERTER ELECTRICAL CHARACTERISTICS Symbol ILOAD Parameter Maximum Non-Continuous Load Current Conditions 3.2V < VIN VOUT = 20V 150 100 3.0V = VIN VOUT = 20V VOUT Output Voltage Accuracy (FB Pin) 3.0V ≤ VIN ≤ 5.5V VOUT = 20V RDSON Switch ON Resistance ISW = 0.5A fPWM PWM Mode Switching Frequency RT = 82 kΩ Frequency Accuracy RT = 82 kΩ tSTARTUP Startup Time IMAX Max 140 Maximum Continuous Load Current Switch Pulse Minimum Width Typ 3.0V ≤ VIN ≤ 3.2V VOUT = 20V ILOAD tPULSE Min Units mA −2.3 -1.7 0.15 +2.3 +1.7 % 0.3 Ω 1.0 MHz −7 +7 −9 +9 % no load 45 ns Boost startup from STANDBY to VOUT = 20V, no load 15 ms SW Pin Current Limit 1500 1850 mA Note: Maximum non-continuous currents rates as short pulses (t < 1s). Exposure to maximum rating conditions for extended periods may affect device reliability. BOOST STANDBY MODE User can set the Boost Converter to STANDBY mode by writing the register bit EN_BOOST low. When EN_BOOST is written high, the converter starts for 20ms in low current PWM mode and then goes to normal PWM mode. All LED outputs are off during the 20ms delay to ensure smooth startup. BOOST OUTPUT VOLTAGE CONTROL User can control the boost output voltage by Boost Output 8-bit register. Boost Output [7:0] Register 0DH Bin Dec 0000 1000 8 Boost Output Voltage Control Boost Output Voltage (typical) 8.0V 0000 1001 9 9.0V 0000 1010 10 10.0V 0000 1011 11 11.0V 0000 1100 12 12.0V 0000 1101 13 13.0V 0000 1110 14 14.0V 0000 1111 15 15.0V 0001 0000 16 16.0V 0001 0001 17 17.0V 0001 0010 18 18.0V 0001 0011 19 19.0V 0001 0100 20 20.0V 20179778 If register value is lower than 8, then value of 8 is used internally. If register value is higher than 20, then value of 20 is used internally. 9 www.national.com LP5526 Boost Converter Typical Performance Characteristics Vin = 3.6V, Vout = 20.0V if not otherwise stated Boost Converter Efficiency Boost Typical Waveforms at 150mA Load 20179779 20179780 Battery Current vs Voltage Boost Output Voltage vs. Current 20179781 20179782 Boost Line Regulation 3.0V - 3.6V, no load Boost Turn On Time with No Load 20179783 www.national.com 20179784 10 Boost Load Transient Response 50mA – 150mA LP5526 Boost Converter Typical Performance Characteristics (Continued) Autoload Effect on Input Current, No Load 20179785 20179786 Boost Maximum Current vs. Output Voltage 20179795 11 www.national.com LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) CONTROL REGISTER (00H) Name Bit LP5526 has one RGB/color LED output, consisting of three individual LED output pins. Output pins can be used in switch mode or constant current mode. Output mode can be selected with the control register (address 00H) bit CC_SW. If the bit is set high, then RGB outputs are in switch mode, otherwise in constant current mode. These modes are described later in separate chapters. RGB_PWM 7 0 = Internal PWM control disabled 1 = Internal PWM control enabled EN_RGB 6 0 = RGB outputs disabled 1 = RGB outputs enabled CC_SW 5 0 = Constant current sink mode 1 = Switch mode RGB LED output control can be done in three ways: 1. Defining the expected color and brightness with internal PWM in RGB register (address 01H) RSW 3 0 = RLED disabled 1 = RLED enabled GSW 2 0 = GLED disabled 1 = GLED enabled BSW 1 0 = BLED disabled 1 = BLED enabled COLOR[3:0] 7:4 Color for RGB LED output BRIGHT[2:0] 3:1 Brightness control OVL 0 2. Direct setting each LED ON/OFF via RGB Control register (address 00H) 3. External PWM control Description RGB REGISTER (01H) 1. BRIGHTNESS CONTROL WITH RGB REGISTER If the RGB LED output is used by defining the balance and brightness in the RGB register, then one needs to set EN_RGB bit high and RGB_PWM bit high in the Control register (address 00H). RSW, GSW and BSW are used to enable each LED output, enabled when written high. CC_SW defines the LED output mode. A single register is used for defining the color and brightness for the RGB LED output. OVL bit selects overlapping/non-overlapping mode. Overlapping mode is selected when OVL = 1. 0 = Non-overlapping mode 1 = Overlapping mode Brightness control is logarithmic and is programmed as follows: Bright[2:0] Brightness [%] Ratio to max brightness 000 0 0 001 1.56 1/64 010 3.12 1/32 011 6.25 1/16 100 12.5 1/8 101 25 1/4 110 50 1/2 111 100 1/1 16 colors can be selected as follows. Please note that exact color depends on RGB LED current and type. Color setting is valid only in non-overlapping mode. COLOR[3:0] RED active [%] GREEN active [%] BLUE active [%] 0000 0001 100 0 0 red 0 100 0 green 0010 0 0 100 blue 0011 50 50 0 yellow 0100 0 50 50 cyan 0101 50 0 50 magenta 0110 33 33 33 white 0111 50 25 25 pink 1000 25 50 25 light green 1001 25 50 25 light blue 1010 25 25 50 orange 1011 75 25 0 deep pink 1100 0 75 25 spring green 1101 25 75 0 lawn green 1110 0 25 75 sky blue 1111 25 0 75 indigo www.national.com 12 RGB COLOR LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) (Continued) Overlapping Mode In overlapping mode the brightness is controlled using PWM duty cycle based control method as the following figure shows. 20179787 Overlapping Mode Since RGB outputs are on simuneltaneously, the maximum load peak current is: IMAX = I(RLED)MAX + I(GLED)MAX + I(BLED)MAX Non-Overlapping Mode The timing diagram shows the splitted R, G and B and brightness control effect to splitted parts. Full brightness is used in the diagram. If for example 1⁄2 brightness is used, the frame is still 50µs, but all LED outputs’ ON time is 50% shorter and at the last 25µs all LED outputs are OFF. 20179788 Non-Overlapping Mode The non-overlapping mode has 16 programmed colors (different R, G and B ratio - > different color). Since the R, G and B are split in to non-overlapping slots the output current through the RGB LED can be calculated with following equation: IAVG=(CRxIR+CGxIG+CBxIB)xB where C = Color [%] (see table of color control) B = Brightness [%] (see table of brightness control) 2. LED ON/OFF CONTROL WITH RGB CONTROL REGISTER Each LED output can be set ON by writing the corresponding bit high in the Control register (00H). RSW controls RLED, GSW controls GLED and BSW controls BLED output. Note that EN_RGB bit must be high and RGB_PWM bit low. In this mode, the RGB register (01H) does not have any effect. CC_SW bit in Control register defines the LED output mode. 13 www.national.com LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) Table with example resistance values and corresponding output currents: RGB resistor RRGB (kΩ) Maximum current / output IMAX (mA) 2.4 50.2 2.7 44.7 3.0 40.3 3.3 36.7 3.6 33.7 3.9 31.1 4.3 28.3 4.7 25.9 5.1 23.9 CONSTANT CURRENT MODE 5.6 21.8 In constant current mode, the maximum output current is defined with a single external resistor (RRGB) and the maximum current control register (address 02H). 6.2 19.7 (Continued) Switch Mode / Constant Current Mode Each RGB LED output can be set to act as a switch or a constant current sink. Selection of mode is done with the CC_SW bit in the Control Register. If bit is set high, then the switch mode is selected. Default is switch mode. SWITCH MODE In switch mode, the RGB LED outputs are low ohmic switches to ground. Resistance is typically 3.2Ω. External ballast resistors must be used to limit the current through the LED. Note that the LED output requires a minimum saturation voltage in order to act as a true constant current sink. The saturation voltage minimum is typically 230mV defined with 10% current drop. If the LED output voltage drops below 230mV, then the current will decrease significantly. RGB MAX CURRENT REGISTER (02H) Name Bit Description IR[1:0] 5:4 RLED maximum current IG[1:0] 3:2 GLED maximum current 3. EXTERNAL PWM CONTROL IB[1:0] 1:0 BLED maximum current The GPIO[0]/PWM pin can be used to control the RGB output brightness or set RGB leds on/off. PWM function for the pin is selected by writing EN_PWM_PIN high in GPIO control register (address 06H). Note, that EN_RGB bit must be set high. Each LED output can be enabled with RSW, GSW and BSW bits. EN_EXT_R_PWM, EN_EXT_G_PWM and EN_EXT_B_PWM bits are used to select, which LED outputs are controlled with the external PWM input. Note that polarity of external PWM control is active high i.e. when pin is in high state, then LED output is enabled. If RGB_PWM is set low, then each selected LED output is controlled directly with external PWM input. If RGB_PWM is set high, then internal PWM control is modulated by the external PWM input. In latter case, internal PWM control is passed to LED when external PWM input is high. Maximum current for each LED output is adjusted with the RGB max current register in following way: IR[1:0], IG[1:0], IB[1:0] Maximum current / output 00 0.25 x IMAX 01 0.50 x IMAX 10 0.75 x IMAX 11 1.00 x IMAX External ballast resistors are not needed in this mode. The maximum current for all RGB LED drivers is set with RRGB. The equation for calculating the maximum current is: IMAX = 100 x 1.23V / (RRGB + 50 Ω) where IMAX = maximum RGB current in any RGB output (during constant current mode) 1.23V = reference voltage 100 = internal current mirror multiplier RRGB = resistor value in Ohms 50 Ω = Internal resistor in the IRGB input www.national.com 14 • Enable external PWM pin by writing EN_PWM_PIN bit high • Use EN_EXT_R_PWM, EN_EXT_G_PWM and EN_EXT_B_PWM bits to select, which LED outputs are controlled by the external PWM control. Output which external PWM control is not selected will be on constantly regardless of the state of the external PWM pin. • Enable RGB constant current mode, if external ballast resistors are not used (CC_SW = 0) • Disable internal RGB PWM mode (RGB_PWM = 0) • Write wanted maximum current values for each output to RGB max current register (e.g. 11b for maximum current) • Enable RGB functions (EN_RGB = 1, RSW= 1, GSW= 1, BSW = 1) • Use external PWM control pin (GPIO[0]/PWM) to introduce pre-flash and flash. (Continued) FLASH LED DRIVING USING RGB DRIVERS RGB drivers can be connected in parallel and used as a flash LED driver (see Typical application 2). Flash LEDs can be powered through the boost converter. Flash LEDs are controlled basically the same way as RGB LEDs controlling is previously described. Additional safety mode is introduced for FLASH LED driving to avoid prolonged flash and damage to application. FLASH can be done in 3 different ways: 1. Using external PWM control 2. Controlling RGB max current register values 3. Using Flash mode 1. Using External PWM control In this case pre-flash brightness is adjusted by adjusting the pulse width of PWM signal 20179702 Using External PWM Control for Flash 2. Controlling RGB Max Current Register Values • Start pre-flash by switching on the LEDs (RSW = 1, GSW = 1, BSW = 1). Pre-flash brightness can be adjusted also by setting on only one or two LEDs during the pre-flash • Start flash by writing each output maximum current values to RGB max current register • Stop flash by switching off the LEDs (RSW = 0, GSW = 0, BSW = 0) In this case pre-flash brightness is adjusted by adjusting the current values in the RGB max current register. Note that in this mode flash control speed and timing depends on the I2C communication speed. • Enable RGB functions and disable PWM mode (EN_RGB = 1, RGB_PWM = 0) • Enable RGB constant current mode (CC_SW = 0) • Write pre-flash values for each output to RGB max current register (e.g. 00b for 25% of maximum current) 15 www.national.com LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) (Continued) 20179703 Controlling RGB Max Current Values to Introduce Flash www.national.com 16 3. Using Flash Mode In this mode Flash is triggered with external PWM pin and pre-flash brightness is adjusted by adjusting the RGB max current values. After flash pulse flash led will be shut down. (Continued) • Write the pre-flash current values to RGB max current register • Enable RGB functions and disable PWM mode (EN_RGB = 1, RGB_PWM = 0) • Enable flash mode (EN_FLASH = 1), make sure GPIO[0]/PWM pin is in low state • Enable external PWM pin (EN_PWM_PIN = 1) • Start pre-flash by switching on the LEDs (RSW = 1, GSW = 1, BSW = 1). Pre-flash brightness can be affected also by setting on only one or two LEDs • Use EN_EXT_R_PWM, EN_EXT_G_PWM and EN_EXT_B_PWM bits to select which LED outputs are used for flash • Start flash pulse by setting GPIO[0]/PWM pin high and stop it by setting GPIO[0]/PWM pin low • During the flash pulse the LED outputs with EN_EXT_x_PWM bit enabled give out maximum current, regardless of RGB max current register value or XSW values Note: EN_FLASH bit must be set low, and then high again before it is possible to make a new flash pulse. When RLED, GLED and BLED are connected together as in Typical Application 1, flash current can be adjusted with 8.33% step in constant current mode by changing RGB max current register values as seen on following table. Note that 0% means that appropriate output is turned off by setting RSW, GSW or BSW bit to 0. IR [%] IG [%] IB [%] Total current [%] 0 0 25 8.33 0 0 50 16.67 0 0 75 25.00 0 0 100 33.33 0 25 100 41.67 0 50 100 50.00 0 75 100 58.33 0 100 100 66.67 25 100 100 75.00 50 100 100 83.33 75 100 100 91.67 100 100 100 100 20179704 Using Flash Mode 17 www.national.com LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) LP5526 Functionality of Color LED Outputs (RLED, GLED, BLED) 1. EN_FLASH = 0: Safety counter starts counting when at least one of the EN_SAFETY_X bits is enabled. Safety counter can be cleared by executing an I2C read or write sequence to address 02H. If safety counter reaches one second, the LEDs which have the safety function enabled, are switched off. Also the read-only bit SAFETY_SET is set high. 2. EN_FLASH = 1: Safety counter starts counting when the external flash trigger pulse starts (GPIO[0]/PWM goes high) and stops counting when flash pulse stops (GPIO[0]/PWM goes low). If flash pulse is longer than one second, the LEDs which have the safety function enabled, are switched off. Also the read-only bit SAFETY_SET is set high. In both cases (EN_FLASH = 0/1) after one second is reached and the LEDs which safety bit has been enabled are switched off, the LED state can be restored by disabling the safety function of the corresponding LED. Counter can be cleared only by disabling all safety bits (EN_SAFETY_R = 0, EN_SAFETY_G = 0, EN_SAFETY_B = 0), I2C read or write sequence to address 02H does not clear the counter when safety function has been activated. (Continued) FLASH SAFETY TIMER FUNCTION Flash safety function can be used to prevent damages due to possible overheating when flash or RGB LEDs have been stuck on because of software or user error. Safety function has two operation modes: 1. Disabling selected RGB drivers when no writing has been done to the RGB max current register (address 02H) for 1 second 2. Disabling selected RGB drivers if the external flash trigger pulse is longer than 1 second Flash safety function can be individually enabled for all RGB LED drivers (EN_SAFETY_R, EN_SAFETY_G, EN_SAFETY_B). The safety function operation mode depends on the state of EN_FLASH bit. RGB LEDs Driver Performance Characteristics Symbol Parameter ILEAKAGE RLED, GLED, BLED pin leakage current Condition IMAX(RGB) Maximum recommended sink current Min Typ Max Units CC mode SW mode Accuracy @ 50mA CC mode 5 Current mirror ratio CC mode 1:100 1 µA 50 mA 60 mA 12.5 % RGB current matching error IRGB set to 50mA, CC mode RSW Switch resistance SW mode 3.2 Ω ƒRGB RGB internal PMW switching frequency Accuracy same as internal clock frequency accuracy 20 kHz VSAT Saturation voltage (current drop 10%) +25oC, IRGB set to 50mA -30oC +85oC 230 2 % 350 300 430 Note: RGB current should be limited as follows: constant current mode – limited by external RRGB resistor switch mode – limited by external ballast resistors Output Current vs Pin Voltage (CC Mode) Output Current vs RRGB (CC Mode) 20179705 www.national.com 20179706 18 mV LP5526 has 2 independent backlight drivers. Both drivers are regulated constant current sinks. LED current for both LED strings are controlled by the 8-bit current mode DACs with 0.1 mA step. MAIN and SUB LEDs can be also controlled with one DAC (MAIN) for better matching allowing the use of larger displays having up to 8 white LEDs by setting DISPL bit to 1. 20179790 SUB output for 2 LEDs (DISPL = 0) 20179789 MAIN output for 4 LEDs (DISPL = 0) 20179791 MAIN and SUB outputs for 8 LEDs (DISPL = 1) EXTERNAL PWM CONTROL The GPIO[0]/PWM pin can be used to control the backlight drivers brightness or set leds on/off. External PWM control is enabled by writing 1 to EN_MAIN_PWM and/or EN_SUB_PWM bits in register address 2BH. GPIO[0]/PWM pin is used as external PWM input when EN_PWM_PIN is set high. PWM input is active high, i.e. LED is activated when in high state. 19 www.national.com LP5526 Backlight Drivers LP5526 Backlight Drivers Adjustment is made with 04H (main current) and with 05H (sub current) registers: (Continued) FADE IN / FADE OUT LP5526 has an automatic fade in and out for main and sub backlight. The fade function is enabled with EN_FADE bit. The slope of the fade curve is set by the SLOPE bit. Fade control for main and sub display is set by FADE_SEL bit. Recommended fading sequence: 1. Set SLOPE 2. 3. Set FADE_SEL Set EN_FADE = 1 4. Set EN_MAIN / EN_SUB = 1 5. 6. Set target WLED value Fading will be done either within 0.65s or 1.3s based on SLOPE selection Fading times apply to full scale change i.e. from 0 to 100% or vice versa. If the current change does not correspond to full scale change, the time will be respectively shorter. See WLED Dimming diagrams for typical fade times. WLED CONTROL REGISTER (03H) Name Bit SLOPE 5 FADE execution time: 0 = 1.3s (full scale) 1 = 0.65s (full scale) Description FADE_SEL 4 FADE selection: 0 = FADE controls MAIN 1 = FADE controls SUB EN_FADE 3 FADE enable 0 = FADE disabled 1 = FADE enabled DISPL 2 Display mode: 0 = MAIN and SUB individual control 1 = MAIN and SUB controlled with MAIN DAC EN_MAIN 1 MAIN enable: 0 = disable 1 = enable EN_SUB 0 SUB enable: 0 = disable 1 = enable Note: if DISPL=1 and FADE_SEL=0 then FADE effects MAIN and SUB www.national.com 20 MAIN CURRENT [7:0] SUB CURRENT [7:0] Driver current, mA (typical) 0000 0000 0 0000 0001 0.1 0000 0010 0.2 0000 0011 0.3 … … … … 1111 1101 25.3 1111 1110 25.4 1111 1111 25.5 Symbol Parameter Conditions Min Typical Max Units mA IMAX Maximum Sink Current ILEAKAGE Leakage Current VSUB, MAIN =20V IMAIN ISUB MAIN Current tolerance SUB Current tolerance IMAIN and ISUB set to 12.8mA (80H) MatchMAIN-SUB Sink Current Matching Error ISINK=12.8mA, DISPL=1 0.2 MatchMAIN-SUB Sink Current Matching Error ISINK=12.8mA, DISPL=0 5 VSAT 95% Saturation Voltage ISINK=25.5mA 11.1 25.5 30 0.003 1 µA 12.8 14.1 mA % 400 % % 500 650 mV Note: Matching is the maximum difference from the average. WLED Dimming, SLOPE=0 WLED Dimming, SLOPE=1 20179739 20179740 WLED Output Current vs. Voltage 20179792 21 www.national.com LP5526 Backlight Driver Electrical Characteristics LP5526 General Purpose I/O Functionality GPIO DATA (07H) LP5526 has three general purpose I/O pins: GPIO[0]/PWM, GPIO[1] and GPIO[2]. GPIO[0]/PWM can also be used as a PWM input for the external LED PWM controlling. GPIO bi-directional drivers are operating from the VDDIO supply domain. GPIO CONTROL (06H) Name Bit 4 OEN[2:0] 2:0 Bit 2:0 Description Data bits GPIO control register is used to set the direction of each GPIO pin. For example, by setting OEN0 bit high the GPIO[0]/PWM pin acts as a logic output pin with data defined DATA0 in GPIO data register. Note, that the EN_PWM_PIN bit overrides OEN0 state by forcing GPIO[0]/PWM to act as PWM input. GPIO[1] and GPIO[2] pins can be selected to be inputs or outputs, defined by OEN1 and OEN2 bit status. PWM functionality is valid only for GPIO[0]/PWM pin. GPIO data register contains the data of GPIO pins. When output direction is selected to GPIO pin, then GPIO data register defines the output pin state. When GPIO data register is read, it contains the state of the pin despite of the pin direction. Registers for GPIO are as follows: EN_PWM_PIN Name DATA[2:0] Description Enable PWM pin 0 = disable 1 = enable GPIO pin direction 0 = input 1 = output Logic Interface Characteristics (VDDIO = 1.65V...VDD1,2 unless otherwise noted) Symbol Parameter Conditions Min Typ Max Units 0.2xVDDIO V LOGIC INPUT SCL, SDA, GPIO[0:2] VIL Input Low Level VIH Input High Level II Logic Input Current fSCL Clock Frequency 0.8xVDDIO V −1.0 1.0 µA 400 kHz LOGIC INPUT NRST VIL Input Low Level VIH Input High Level 1.2 II Input Current -1.0 tNRST Reset Pulse Width 0.5 V V 1.0 10 µA µs LOGIC OUTPUT SDA VOL Output Low Level ISDA = 3mA VOH Output High Level ISDA = -3mA IL Output Leakage Current VSDA = 2.8V 0.3 VDDIO − 0.5 0.5 V 1.0 µA 0.5 V 1.0 µA VDDIO − 0.3 LOGIC OUTPUT GPIO[0:2] VOL Output Low Level VOH Output High Level IGPIO = -3 mA IL Output Leakage Current VGPIO = 2.8V www.national.com IGPIO = 3 mA 0.3 VDDIO − 0.5 22 VDDIO − 0.3 V LP5526 I2C Compatible Interface I2C SIGNALS TRANSFERRING DATA The SCL pin is used for the I2C clock and the SDA pin is used for bidirectional data transfer. Both these signals need a pull-up resistor according to I2C specification. Every byte put on the SDA line must be eight bits long, with the most significant bit (MSB) being transferred first. Each byte of data has to be followed by an acknowledge bit. The acknowledge related clock pulse is generated by the master. The transmitter releases the SDA line (HIGH) during the acknowledge clock pulse. The receiver must pull down the SDA line during the 9th clock pulse, signifying an acknowledge. A receiver which has been addressed must generate an acknowledge after each byte has been received. After the START condition, the I2C master sends a chip address. This address is seven bits long followed by an eighth bit which is a data direction bit (R/W). The LP5526 address is 59H (101 1001b). For the eighth bit, a “0” indicates a WRITE and a “1” indicates a READ. This means that the first byte is B2H for WRITE and B3H for READ. The second byte selects the register to which the data will be written. The third byte contains data to write to the selected register. I2C DATA VALIDITY The data on SDA line must be stable during the HIGH period of the clock signal (SCL). In other words, state of the data line can only be changed when CLK is LOW. 20179749 I2C Signals: Data Validity I2C START AND STOP CONDITIONS START and STOP bits classify the beginning and the end of the I2C session. START condition is defined as SDA signal transitioning from HIGH to LOW while SCL line is HIGH. STOP condition is defined as the SDA transitioning from LOW to HIGH while SCL is HIGH. The I2C master always generates START and STOP bits. The I2C bus is considered to be busy after START condition and free after STOP condition. During data transmission, I2C master can generate repeated START conditions. First START and repeated START conditions are equivalent, function-wise. 20179751 I2C Chip Address Register changes take an effect at the SCL rising edge during the last ACK from slave. 20179750 I2C Start and Stop Conditions 23 www.national.com LP5526 I2C Compatible Interface (Continued) 20179793 w = write (SDA = “0”) r = read (SDA = “1”) ack = acknowledge (SDA pulled down by either master or slave) rs = repeated start id = 7-bit chip address, 59H (101 1001b) for LP5526. I2C Write Cycle When a READ function is to be accomplished, a WRITE function must precede the READ function, as shown in the Read Cycle waveform. 20179794 I2C Read Cycle www.national.com 24 LP5526 I2C Compatible Interface (Continued) 20179754 I2C Timing Diagram I2C TIMING PARAMETERS (VDD1,2 = 3.0 to 4.5V, VDDIO = 1.8V to VDD1,2) Symbol Limit Parameter Min Max Units 1 Hold Time (repeated) START Condition 0.6 µs 2 Clock Low Time 1.3 µs 3 Clock High Time 600 ns 4 Setup Time for a Repeated START Condition 600 ns 5 Data Hold Time (Output direction, delay generated by LP5526) 300 900 ns 5 Data Hold Time (Input direction, delay generated by Master) 0 900 ns 6 Data Setup Time 7 Rise Time of SDA and SCL 20+0.1Cb 300 ns 8 Fall Time of SDA and SCL 15+0.1Cb 300 ns 100 ns 9 Set-up Time for STOP condition 600 ns 10 Bus Free Time between a STOP and a START Condition 1.3 µs Cb Capacitive Load for Each Bus Line 10 200 pF NOTE: Data guaranteed by design 25 www.national.com LP5526 Recommended External Components rent (1500mA) to ensure reliable operation. Schottky diodes with a low forward drop and fast switching speeds are ideal for increasing efficiency in portable applications. Choose a reverse breakdown voltage of the schottky diode significantly larger (~30V) than the output voltage. Do not use ordinary rectifier diodes, since slow switching speeds and long recovery times cause the efficiency and the load regulation to suffer. Examples of suitable diodes are: Central Semiconductor CMMSH1-40, Infineon BAS52-02V. OUTPUT CAPACITOR, COUT The output capacitor COUT directly affects the magnitude of the output ripple voltage. In general, the higher the value of COUT, the lower the output ripple magnitude. Multilayer ceramic capacitors with low ESR are the best choice. At the lighter loads, the low ESR ceramics offer a much lower VOUT ripple that the higher ESR tantalums of the same value. At the higher loads, the ceramics offer a slightly lower VOUT ripple magnitude than the tantalums of the same value. However, the dv/dt of the VOUT ripple with the ceramics is much lower that the tantalums under all load conditions. Capacitor voltage rating must be sufficient, 25V or greater is recommended. Examples of suitable capacitors are: TDK C3216X5R1E475K, Panasonic ECJ3YB1E475K, ECJMFB1E475K and ECJ4YB1E475K. EMI FILTER COMPONENTS CSW, RSW EMI filter (RSW and CSW) on the SW pin can be used to suppress EMI caused by fast switching. These components should be as near as possible to the SW pin to ensure reliable operation. 50V or greater voltage rating is recommended for capacitor. Some ceramic capacitors, especially those in small packages, exhibit a strong capacitance reduction with the increased applied voltage (DC bias effect). The capacitance value can fall below half of the nominal capacitance. Too low output capacitance can make the boost converter unstable. Output capacitors DC bias effect should be better than –50% at 20V. INDUCTOR, L1 A 10uH shielded inductor is suggested for LP5526 boost converter. The inductor should have a saturation current rating higher than the rms current it will experience during circuit operation (1300mA). Less than 300mΩ ESR is suggested for high efficiency and sufficient output current. Open core inductors cause flux linkage with circuit components and interfere with the normal operation of the circuit. This should be avoided. For high efficiency, choose an inductor with a high frequency core material such as ferrite to reduce the core losses. To minimize radiated noise, use a toroid, pot core or shielded core inductor. The inductor should be connected to the SW pin as close to the IC as possible. Examples of suitable inductors are: TDK SLF6028T-100M1R3, Coilcraft MSS6122-103MLB. INPUT CAPACITOR, CIN The input capacitor CIN directly affects the magnitude of the input ripple voltage and to a lesser degree the VOUT ripple. A higher value CIN will give a lower VIN ripple. Capacitor voltage rating must be sufficient, 10V or greater is recommended. OUTPUT DIODE, D1 A schottky diode should be used for the output diode. Peak repetitive current should be greater than inductor peak curLIST OF RECOMMENDED EXTERNAL COMPONENTS Symbol Value Unit CVDD C between VDD1,2 and GND 100 nF CVDDIO C between VDDIO and GND 100 nF Ceramic, X7R / X5R CVDDA C between VDDA and GND 1 µF Ceramic, X7R / X5R COUT CIN Symbol explanation 2 x 4.7 or 1 x 10 µF Maximum DC bias effect @ 20V C between FB and GND -50 % C between battery voltage and GND 10 µF Ceramic, X7R / X5R, tolerance +/-10% Ceramic, X7R / X5R 10 µH Saturation current 1300 mA CVREF C between VREF and GND 100 nF Ceramic, X7R / X5R RRGB R between IRGB and GND 2.4 kΩ 82 kΩ ± 1% ± 1% L1 RRT L between SW and VBAT Type Ceramic, X7R / X5R R between IRT and GND Rectifying diode (Vf @ maxload) D1 Reverse voltage 0.3-0.5 V 30 V Shielded inductor, low ESR Schottky diode Repetitive peak current 1500 mA CSW C in EMI filter 100 pF Ceramic, X7R / X5R, 50V RSW R in EMI filter 390 Ω ± 1% LEDs User Defined Note: See Application Note AN-1442 "Design and Programming Examples for Lighting Management Unit LP5526" for more information on how to design with LP5526 www.national.com 26 REGISTER Control Register RGB RGB max current WLED Control MAIN Current SUB Current GPIO Control GPIO Data Enables Boost Output PWM Enable ADDR (HEX) 00 01 02 03 04 05 06 07 0B 0D 2B 0 0 EN_SAFETY_G 0 EN_SAFETY_R 0 0 EN_SAFETY_B 0 0 0 EN_BOOST 0 0 0 0 0 0 1 0 0 GSW D2 0 EN_EXT_B_PWM 0 1 EN_AUTOLOAD 0 0 0 0 0 DISPL 0 0 BRIGHT[2:0] IG[1:0] EN_EXT_G_PWM BOOST[7:0] 0 EN_FLASH SUB[7:0] EN_EXT_R_PWM 0 0 0 0 0 RSW D3 EN_FADE MAIN[7:0] EN_PWM_PIN 0 0 FADE_SEL SLOPE 0 0 IR[1:0] 0 D4 0 0 1 NSTBY 0 0 0 0 0 0 SAFETY_SET D5 CC_SW COLOR[3:0] 0 0 0 EN_RGB RGB_PWM 0 D6 D7 LP5526 Control Register Names and Default Values 0 0 0 0 0 0 0 EN_SUB 0 0 OVL D0 0 EN_SUB_PWM IB[1:0] EN_MAIN_PWM 0 0 DATA[2:0] 0 OEN[2:0] 0 0 0 EN_MAIN 0 0 0 BSW D1 LP5526 27 www.national.com LP5526 LP5526 Register Bit Explanations Each register is shown with a key indicating the accessibility of the each individual bit, and the initial condition: Register Bit Accessibility and Initial Condition Key Bit Accessibility RW Read/write R Read only –0,–1 Condition after POR CONTROL REGISTER (00H) – RGB LEDS CONTROL REGISTER D7 D6 D5 RGB_PWM EN_RGB CC_SW RW - 0 RW - 0 RW - 1 D4 R-0 D3 D2 D1 RSW GSW BSW RW - 0 RW - 0 RW - 0 RGB_PWM Bit 7 0 - Internal RGB PWM control disabled 1 - Internal RGB PWM control enabled EN_RGB Bit 6 0 – RGB outputs disabled 1 – RGB outputs enabled CC_SW Bit 5 0 – Constant current sink mode 1 – Switch mode RSW Bit 3 0 – RLED disabled 1 – RLED enabled GSW Bit 2 0 – GLED disabled 1 – GLED enabled BSW Bit 1 0 – BLED disabled 1 – BLED enabled D0 R-0 RGB (01H) – RGB COLOR AND BRIGHTNESS CONTROL REGISTER D7 D6 D5 D4 D3 COLOR[3:0] RW - 0 RW - 0 RW - 0 RW - 0 RW - 0 RW - 0 COLOR[3:0] Bits 7-4 BRIGHT[2:0] Bits 3-1 PWM brightness control for RGB outputs Bit 0 0 – Overlapping mode disabled 1 – Overlapping mode enabled OVL www.national.com D2 D1 BRIGHT[2:0] PWM color for RGB outputs 28 D0 OVL RW - 0 RW - 0 LP5526 LP5526 Register Bit Explanations (Continued) RGB MAX CURRENT (02H) – MAXIMUM RGB CURRENT CONTROL REGISTER D7 D6 D5 D4 SAFETY_SET R-0 D3 IR[1:0] R-0 RW - 0 D2 D1 IG[1:0] RW - 0 RW - 0 D0 IB[1:0] RW - 0 SAFETY_SET Bit 7 0 – safety function not activated 1 – safety function activated IR[1:0] Bits 5-4 RLED maximum current IG[1:0] Bits 3-2 GLED maximum current IB[1:0] Bits 1-0 BLED maximum current RW - 0 RW - 0 Maximum current for RGB driver IR,IG,IB[1:0] Maximum output current 00 0.25 x IMAX 01 0.50 x IMAX 10 0.75 x IMAX 11 1.00 x IMAX WLED CONTROL (03H) – WLED CONTROL REGISTER D7 R-0 D6 R-0 D5 D4 D3 D2 D1 D0 SLOPE FADE_SEL EN_FADE DISPL EN_MAIN EN_SUB RW - 0 RW - 0 RW - 0 RW - 0 RW - 0 RW - 0 SLOPE Bit 5 0 – fade execution time 0.65 sec (full scale) 1 – fade execution time 1.3 sec (full scale) FADE_SEL Bit 4 0 – fade control for MAIN 1 – fade control for SUB EN_FADE Bit 3 0 – automatic fade disabled 1 – automatic fade enabled DISPL Bit 2 0 - MAIN and SUB individual control 1 - MAIN and SUB controlled with MAIN DAC EN_MAIN Bit 1 0 – MAIN output disabled 1 – MAIN output enabled EN_SUB Bit 0 0 – SUB output disabled 1 – SUB output enabled 29 www.national.com LP5526 LP5526 Register Bit Explanations (Continued) MAIN CURRENT (04H) – MAIN CURRENT CONTROL REGISTER D7 D6 D5 D4 D3 D2 D1 D0 RW - 0 RW - 0 RW - 0 RW - 0 D3 D2 D1 D0 RW - 0 RW - 0 RW - 0 RW - 0 D1 D0 MAIN[7:0] RW - 0 RW - 0 RW - 0 RW - 0 SUB CURRENT (05H) – SUB CURRENT CONTROL REGISTER D7 D6 D5 D4 SUB[7:0] RW - 0 RW - 0 RW - 0 RW - 0 MAIN, SUB current adjustment MAIN[7:0], SUB[7:0] Typical driver current (mA) 0000 0000 0 0000 0001 0.1 0000 0010 0.2 0000 0011 0.3 0000 0100 0.4 … … 1111 1101 25.3 1111 1110 25.4 1111 1111 25.5 GPIO CONTROL (06H) – GPIO CONTROL REGISTER D7 D6 D5 D4 D3 D2 EN_PWM_PIN R-0 R-0 R-0 OEN[2:0] RW - 0 R-0 RW - 0 EN_PWM_PIN Bit 4 0 – External PWM pin disabled 1 – External PWM pin enabled OEN[2:0] Bits 2-0 0 – GPIO pin set as a input 1 – GPIO pin set as a output RW - 0 RW - 0 GPIO DATA (07H) – GPIO DATA REGISTER D7 D6 D5 D4 D3 D2 R-0 R-0 R-0 R-0 R-0 RW - 0 DATA[2:0] Bits 2-0 D1 D0 DATA[2:0] www.national.com GPIO data register bits 30 RW - 0 RW - 0 LP5526 LP5526 Register Bit Explanations (Continued) ENABLES (0BH) – ENABLES REGISTER D7 R-0 D6 D5 NSTBY EN_BOOST RW - 0 RW - 0 D4 D3 D2 EN_FLASH EN_AUTOLOAD RW - 0 RW - 1 R-0 NSTBY Bit 6 0 – LP5526 standby mode 1 – LP5526 active mode EN_BOOST Bit 5 0 – Boost converter disabled 1 – Boost converter enabled EN_FLASH Bit 3 0 – Flash function disabled 1 – Flash function enabled EN_AUTOLOAD Bit 2 0 – Boost active load disabled 1 – Boost active load enabled D1 D0 R-0 R-0 BOOST OUTPUT (0DH) – BOOST OUTPUT VOLTAGE CONTROL REGISTER D7 D6 D5 D4 D3 D2 D1 D0 RW - 1 RW - 0 RW - 0 RW - 0 BOOST[7:0] RW - 0 RW - 0 RW - 0 RW - 0 BOOST output voltage adjustment BOOST[7:0] Typical boost output voltage (V) 0000 1000 8.00 0000 1001 9.00 0000 1010 10.00 0000 1011 11.00 0000 1100 12.00 0000 1101 13.00 0000 1110 14.00 0000 1111 15.00 0001 0000 16.00 0001 0001 17.00 0001 0010 18.00 0001 0011 19.00 0001 0100 20.00 31 www.national.com LP5526 LP5526 Register Bit Explanations (Continued) PWM ENABLE (2BH) – EXTERNAL PWM CONTROL REGISTER D7 D6 D5 D4 D3 D2 D1 D0 EN_EXT G_PWM EN_EXT B_PWM EN_MAIN PWM EN_SUB PWM RW - 0 RW - 0 RW - 0 RW - 0 EN_SAFETY_R EN_SAFETY_G EN_SAFETY_B EN_EXT R_PWM RW - 0 RW - 0 RW - 0 RW - 0 EN_SAFETY_R Bit 7 0 – Safety function for RLED disabled 1 – Safety function for RLED enabled EN_SAFETY_G Bit 6 0 – Safety function for GLED disabled 1 – Safety function for GLED enabled EN_SAFETY_B Bit 5 0 – Safety function for BLED disabled 1 – Safety function for BLED enabled EN_EXT_R_PWM Bit 4 0 – External PWM control for RLED disabled 1 – External PWM control for RLED enabled EN_EXT_G_PWM Bit 3 0 – External PWM control for GLED disabled 1 – External PWM control for GLED enabled EN_EXT_B_PWM Bit 2 0 – External PWM control for BLED disabled 1 – External PWM control for BLED enabled EN_EXT_MAIN_PWM Bit 1 0 – External PWM control for MAIN disabled 1 – External PWM control for MAIN enabled EN_EXT_SUB_PWM Bit 0 0 – External PWM control for SUB disabled 1 – External PWM control for SUB enabled www.national.com 32 inches (millimeters) unless otherwise noted The dimension for X1 ,X2 and X3 are as given: • X1=2.543mm ± 0.03mm • X2=2.543mm ± 0.03mm • X3=0.60mm ± 0.075mm 25-bump micro SMD Package, 2.54 x 2.54 x 0.6mm, 0.5mm pitch NS Package Number TLA25CCA See Application note AN–1112 for PCB design and assembly instructions. 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National Semiconductor Americas Customer Support Center Email: [email protected] Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 National Semiconductor Asia Pacific Customer Support Center Email: [email protected] National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: [email protected] Tel: 81-3-5639-7560 LP5526 Lighting Management Unit with High Voltage Boost Converter with up to 150mA Serial FLASH LED Driver Physical Dimensions