LED Drivers for LCD Backlights Backlight LED Drivers for Small LCD Panels (Charge Pump Type) BD1604MUV, BD1604MVV No.11040EBT23 ●Description This LSI is a 4 white LED driver for small LCD backlight. At the charge pump type, the number of external devices is minimized. ●Features 1) 4 parallel LED driver is mounted. 2) The LED current can be controlled via an external resistance. 3) Maximum current is 120mA (30mA × 4). 4) LED1 to LED4 can be turned on or off via an external control pin. 5) The relative current accuracy among LEDs (LED1 to LED4) is 3%. 6) Automatically transition to each mode (×1.0, ×1.5, ×2.0). 7) High efficiency (90% or more at maximum) is achieved. 8) Various protection functions such as output voltage protection function, current overload limiter and thermal shutdown circuit are mounted. ●Applications This driver provides for: - Backlight using white LED - Auxiliary lights for mobile phone cameras and simplified flash ●Lineup Parameter BD1604MUV BD1604MVV 4ch 4ch 120mA 120mA VQFN016V3030 3.00mm×3.00mm SQFN016V4040 4.00mm×4.00mm Number of LED channels Maximum current Package ●Absolute Maximum Rating (Ta=25℃) Parameter Power supply voltage Symbol Ratings Unit Vmax 7 V 1 BD1604MUV Allowable loss 700 * Pd BD1604MVV 780 *2 mW Operating temperature range Topr -30~85 ℃ Storage temperature range Tstr -55~150 ℃ *1 *2 When a glass epoxy substrate (70mm×70mm×1.6mm) has been mounted, this loss will decrease 5.6mW/℃ if Ta is higher than or equal to 25℃. When a glass epoxy substrate (70mm×70mm×1.6mm) has been mounted, this loss will decrease 6.24mW/℃ if Ta is higher than or equal to 25℃. ●Recommended Operation Range Parameter Operating supply voltage www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. Symbol Limits Unit VBAT 2.7~5.5 V 1/10 Condition VBAT voltage 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV ●Electrical Characteristics Unless otherwise specified, Ta is 25℃ and VBAT is 3.6V. Parameter Symbol Limits Unit Condition Min. Typ. Max. IQ0 - 0.1 1 μA EN=0V Circuit current 1.0 IQ1.0 - 1.0 2.0 mA x1.0 Mode, Iout = 0mA Circuit current 1.5 IQ1.5 - 2.3 3.3 mA x1.5 Mode, Iout = 0mA Circuit current 2.0 IQ2.0 - 2.5 3.5 mA X2.0 Mode, Iout = 0mA [Circuit current] Circuit current 0 Unless otherwise specified, Ta is 25℃ and VBAT is 3.6V. Parameter Symbol Limits Min. Typ. Max. Unit Condition [Current driver] LED maximum current ILEDmax - - 30 mA LED current accuracy ILEDdiff - 0.5 5.0 % ILED=10mA LED current matching ILEDmatch - 0.5 3.0 % ILED=10mA *1) LED pin control voltage VLED 0.08 0.10 0.20 V Minimum voltage at LED1~LED4 pins ISET voltage ISET 0.5 0.6 0.7 V Oscillation frequency Fosc 0.8 1.0 1.2 MHz Over current limiter IOV - 600 900 mA LED current limiter ILEDOV 40 60 100 mA *1) LED current matching = (ILEDmax-ILEDmin)/(ILEDmax+ILEDmin)*100 ILEDmax : Maximum value of LED1-4 current ILEDmin : Minimum value of LED1-4 current Unless otherwise specified, Ta is 25℃ and VBAT is 5.5V. Parameter Symbol Limits Min. Typ. Max. Unit Condition [Control Signal etc.] Input ’H’ voltage VIH 1.4 - - V EN,SEL0,SEL1,SEL2 Input ’L’ voltage VIL - - 0.4 V EN,SEL0,SEL1,SEL2 Input ‘H’ current1 IIH1 - 18.3 30 μA EN=5.5V Input ‘H’ current2 IIH2 - 0 1 μA SEL0,SEL1,SEL2=5.5V Input ‘L’ current IIL -1 0 - μA EN,SEL0,SEL1,SEL2=0V Unless otherwise specified, Ta is 25℃ and VBAT is 3.6V. Parameter Symbol Limits Min. Typ. Max. 1.9 2.2 2.5 Unit Condition [Control Signal etc.] UVLO detecting voltage www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. VUVLO 2/10 V 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV ●Reference Data (Evaluation under LED VF=3.2V) 100 2 0.4 0.3 0.2 Ta=85℃ Ta=25℃ Ta=-30℃ 0.1 90 1.5 EFFICIENCY [%] Current Consumption : IQ1.0 [µA] STAND-BY Current : Istb [µA] 0.5 Ta=85℃ 1 Ta=25℃ DOWN 80 70 60 0.5 50 UP Ta=-30℃ 0 0 3 3.5 4 4.5 5 INPUT VOLTAGE : VBAT[V] 5.5 0 1 2 3 4 INPUT VOLTAGE : VBAT[V] Fig.1 Circuit Current (Standby) 40 2.5 5 100 90 90 5.5 Fig.3 Efficiency Hysteresis (20mA × 4 LEDs) Fig.2 Circuit Current (×1.0 Mode Operation) 100 3 3.5 4 4.5 5 SUPPLY VOLTAGE : VBAT[V] 100 Ta=-30℃ 90 60 50 80 70 60 Ta=25℃ 50 40 2.5 3 3.5 4 4.5 5 SUPPLY VOLTAGE : VBAT[V] 60 Ta=25℃ Ta=85℃ 3 3.5 4 4.5 5 SUPPLY VOLTAGE : VBAT[V] 40 2.5 5.5 15 10 5 0 20 Ta=25℃ LED CURRENT : ILED [mA] LED CURRENT : ILED [mA] Ta=25℃ Ta=-30℃ Ta=-30℃ 15 10 5 1.2 Ta=85℃ 20 Ta=25℃ Ta=-30℃ 15 10 5 0 0 0.3 0.6 0.9 LED VOLTAGE : VLED[V] 5.5 25 Ta=85℃ Ta=85℃ 20 3 3.5 4 4.5 5 SUPPLY VOLTAGE : VBAT[V] Fig.6 Efficiency (20mA × 4 LEDs) 25 25 LED CURRENT : ILED [mA] 70 Fig.5 Efficiency (15mA × 4 LEDs) Fig.4 Efficiency (5mA × 4 LEDs) 0 80 50 Ta=85℃ 40 2.5 5.5 EFFICIENCY [%] 70 EFFICIENCY [%] EFFICIENCY [%] Ta=-30℃ Ta=85℃ Ta=25℃ Ta=-30℃ 80 0 0.3 0.6 0.9 LED VOLTAGE : VLED[V] 1.2 Fig.8 LED Current (20mA) (VBAT=3.6V) Fig.7 LED Current (20mA) (VBAT=2.7V) 0 0.3 0.6 0.9 LED VOLTAGE : VLED[V] 1.2 Fig.9 LED Current (20mA) (VBAT=5.5V) 25 35 30 20 ILED [mA] ILED [mA] 25 20 15 15 10 10 5 5 0 0 0 50 100 RSET[kO] 150 200 Fig.10 LED Current vs. RSET (Ta=25℃) www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 0 20 40 60 PWM DUTY[%] 80 100 Fig.11 LED Current vs. PWM Duty (Cycle 100Hz) 3/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV GND C2P C2N C1N ●Block Diagram, Recommended Circuit Example and Pin Location Diagram 12 11 10 9 LED1 13 8 C1P 7 VBAT LED3 15 6 VOUT LED4 16 5 ISET LED2 14 SEL0 3 4 SEL2 2 EN 1 SEL1 BD1604MUV BD1604MVV Fig.12 Pin Location Diagram (Top View) C1P C2N C1N C2P C2 C1 Battery ×1, ×1.5, ×2 Charge pump VBAT Cin VOUT Cout Over Voltage Protect Charge Pump Mode Control EN OSC Vout Control SEL0 Control LED1 TSD SEL1 LED2 LED3 SEL2 LED4 ISET Resistor Driver ISET Rset Current Driver GND Fig.13 Block Diagram and Recommended Circuit Diagram www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 4/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV [Pin table] Pin number BD1604MUV BD1604MVV Pin circuit diagram EN 1 1 F SEL0 2 2 E SEL1 3 3 E SEL2 4 4 E ISET 5 5 G VOUT 6 6 C VBAT 7 7 H C1P 8 8 B Pin name C1N 9 9 A C2N 10 10 A C2P 11 11 B GND 12 12 I LED1 13 13 D LED2 14 14 D LED3 15 15 D LED4 16 16 D ●I/O Equivalence Circuit Diagram The following shows I/O equivalence circuits. A PAD B PAD E PAD C PAD F PAD D PAD G PAD H PAD I PAD Fig.14 Pin Diagram www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 5/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV ●Description of Block Operations 1) LED light control and current control When LED lights are controlled, H- or L-level voltage is applied to respective control pins. Current control in the BD1604MUV/MVV can take place via a resistance connected to the ISET pin. ON/OFF control SEL2 SEL1 0 0 0 0 0 1 0 1 1 0 1 0 1 1 1 1 SEL0 0 1 0 1 0 1 0 1 Rset: See the following table. 0: 0V, 1: VBAT LED1 OFF OFF OFF ON OFF OFF ON OFF LED2 OFF OFF ON OFF OFF ON ON OFF LED3 OFF ON OFF OFF ON ON ON OFF LED4 ON OFF OFF OFF ON ON ON OFF When handling pins, the LED pins must be connected to VBAT so long as LED is always OFF. Current control Rset 165kΩ 97.6kΩ 48.7kΩ ILED 3mA 5mA 10mA The LED current can be changed by the Rset value. ILED=480/Rset The above expression can be used for approximation. 32.4kΩ 15mA 24.3kΩ 20mA 16.2kΩ 30mA 2) Low supply voltage detection circuit (UVLO) When the IC-applied supply voltage drops, all the circuits including the DC/DC converter are stopped. When supply voltage drops to a detecting voltage, UVLO is activated. When it rises, UVLO is automatically released. 3) Soft start by DC/DC converter startup When a DC/DC converter is started, soft start is enabled so that output voltage can be increased gradually to prevent output voltage overshooting. ●Application Parts Selection Method Capacitor (Use the ceramics parts with good frequency and temperature characteristics.) Symbol Recommended value Recommended part Resistance Symbol 1μF GRM188B11A105KA61B(MURATA) Ceramics capacitor Recommended value Recommended part Set Current Value Rset ~ 16kΩ 30mA MCR006YZPF Series (ROHM) 240kΩ ~ Cout,Cin,C1,C2 Type 2mA Connect an input bypass capacitor (CIN) between VBAT and GND pin in proximity. In addition, connect an output capacitor between VOUT and GND pins in proximity. Connect a capacitor between C1P and C1N and also a capacitor between C2P and C2N in proximity to the chips. Connect a resistance in proximity to the ISET pin. When other than these parts are used, the equivalent parts must be used. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 6/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV ●Cautions on layout pattern When designing a layout pattern, lay out wires to a power line in a way that the layout pattern impedance can be minimized and connect a bypass capacitor if necessary. LED VOUT 1μF RSET LED GND VBAT LED 1μF 1μF 1μF GND LED The GND pin and Cin must be placed nearby. Wiring from the VBAT pin to Cin must meet a low impedance. Fig.15 Example of BD1604MUV Layout Pattern (Front, Top View) Fig.16 Example of BD1604MUV Layout Pattern (Rear, Top View) ●LED Current Control There are two methods for LED current control. One method uses an external PWM signal and another changes the resistance value of RREF (RSET) connected to the IREF (ISET) pin. For details, refer to the respective circuit examples. Don’t make the setting of 30mA or more per channel for BD1604MUV/MVV. 1) Controlling the current by using the PWM method The PWN signal must be input to the EN pin. PWM signal “H” level: 1.4V or more PWM signal “L” level: 0.4V or less When PWM Duty is used in an area of 10% or less, the PWM cycle must be a range from 100Hz to 200Hz. When extremely high-speed PWM control takes place, the linearity of LED current value to PWM duty is lost if the PWM duty is small (for example, 10% or less) or it is large (for example, 90% or more). 2) Controlling the current by changing the SET resistance value Rset-Rset1=Rset2// … //Restn. This means that the current can be adjusted more finely by adding the types of resistance values. ILED=480/Rset [A] The approximate LED current can be obtained from the above expression. Because the current of 30mA or more per LED is not permitted, make the setting in a way that the Rset resistance value can be maintained to be greater than or equal to16kΩ. C1P C2N C1N C2P C1P C2N C1N C2 C1 Battery C2P C2 C1 Battery ×1, ×1.5, ×2 Charge pump VBAT Cin VOUT ×1, ×1.5, ×2 Charge pump VBAT Cin VOUT Cout Cout Over Voltage Over Voltage Protect Protect Charge Pum p Charge Pum p Mode C ontrol Mode C ontrol EN EN OSC PWM signal input (ON for the signal set to High) SEL0 Vout Control Control SEL1 Control LED1 TSD SEL1 LED2 LED3 SEL2 Vout Control SEL0 LED1 TSD OSC LED2 LED3 SEL2 LED4 ISET Rset ISET Resistor Driver LED4 ISET Current Driver Rsetn GND www.rohm.com Rset1 ISET Resistor Driver Current Driver GND Fig.18 Controlling the Current by Changing the Resistance Value Fig.17 Controlling the Current by Using the PWM Method © 2011 ROHM Co., Ltd. All rights reserved. Rset2 7/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV ●Notes for Use (1) Absolute Maximum Ratings An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc., can break down devices, thus making impossible to identify breaking mode such as a short circuit or an open circuit. If any special mode exceeding the absolute maximum ratings is assumed, consideration should be given to take physical safety measures including the use of fuses, etc. (2) Operating conditions These conditions represent a range within which characteristics can be provided approximately as expected. The electrical characteristics are guaranteed under the conditions of each parameter. (3) Reverse connection of power supply connector The reverse connection of power supply connector can break down ICs. Take protective measures against the breakdown due to the reverse connection, such as mounting an external diode between the power supply and the IC’s power supply terminal. (4) Power supply line Design PCB pattern to provide low impedance for the wiring between the power supply and the GND lines. In this regard, for the digital block power supply and the analog block power supply, even though these power supplies has the same level of potential, separate the power supply pattern for the digital block from that for the analog block, thus suppressing the diffraction of digital noises to the analog block power supply resulting from impedance common to the wiring patterns. For the GND line, give consideration to design the patterns in a similar manner. Furthermore, for all power supply terminals to ICs, mount a capacitor between the power supply and the GND terminal. At the same time, in order to use an electrolytic capacitor, thoroughly check to be sure the characteristics of the capacitor to be used present no problem including the occurrence of capacity dropout at a low temperature, thus determining the constant. (5) GND voltage Make setting of the potential of the GND terminal so that it will be maintained at the minimum in any operating state. Furthermore, check to be sure no terminals are at a potential lower than the GND voltage including an actual electric transient. (6) Short circuit between terminals and erroneous mounting In order to mount ICs on a set PCB, pay thorough attention to the direction and offset of the ICs. Erroneous mounting can break down the ICs. Furthermore, if a short circuit occurs due to foreign matters entering between terminals or between the terminal and the power supply or the GND terminal, the ICs can break down. (7) Operation in strong electromagnetic field Be noted that using ICs in the strong electromagnetic field can malfunction them. (8) Inspection with set PCB On the inspection with the set PCB, if a capacitor is connected to a low-impedance IC terminal, the IC can suffer stress. Therefore, be sure to discharge from the set PCB by each process. Furthermore, in order to mount or dismount the set PCB to/from the jig for the inspection process, be sure to turn OFF the power supply and then mount the set PCB to the jig. After the completion of the inspection, be sure to turn OFF the power supply and then dismount it from the jig. In addition, for protection against static electricity, establish a ground for the assembly process and pay thorough attention to the transportation and the storage of the set PCB. (9) Input terminals In terms of the construction of IC, parasitic elements are inevitably formed in relation to potential. The operation of the parasitic element can cause interference with circuit operation, thus resulting in a malfunction and then breakdown of the input terminal. Therefore, pay thorough attention not to handle the input terminals, such as to apply to the input terminals a voltage lower than the GND respectively, so that any parasitic element will operate. Furthermore, do not apply a voltage to the input terminals when no power supply voltage is applied to the IC. In addition, even if the power supply voltage is applied, apply to the input terminals a voltage lower than the power supply voltage or within the guaranteed value of electrical characteristics. (10) Ground wiring pattern If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND pattern from the small-signal GND pattern and establish a single ground at the reference point of the set PCB so that resistance to the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of the small-signal GND. Pay attention not to cause fluctuations in the GND wiring pattern of external parts as well. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 8/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV (11) External capacitor In order to use a ceramic capacitor as the external capacitor, determine the constant with consideration given to a degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature, etc. (12) Not connecting input terminals In terms of extremely high impedance of CMOS gate, to open the input terminals causes unstable state. Unstable state occurs from the inside gate voltage of p-channel or n-channel transistor into active. As a result, power supply current may increase. And unstable state can also cause unexpected operation of IC. So unless otherwise specified, input terminals not being used should be connected to the power supply or GND line. (13) Thermal shutdown circuit (TSD) When junction temperatures become setting temperature or higher, the thermal shutdown circuit operates and turns a switch OFF. The thermal shutdown circuit, which is aimed at isolating the LSI from thermal runaway as much as possible, is not aimed at the protection or guarantee of the LSI. Therefore, do not continuously use the LSI with this circuit operating or use the LSI assuming its operation. (14) Thermal design Perform thermal design in which there are adequate margins by taking into account the permissible dissipation (Pd) in actual states of use. ●Thermal Loss The following conditions must be met for thermal design. (Because the following temperature is only the assured temperature, be sure to consider the margin for design.) 1. The ambient temperature Ta must be 85˚C. 2. The IC loss must be smaller than an allowable loss (Pd). ●Power dissipation character The following shows the power dissipation character. 1 0.78W 0.8 POWER DISSIPATION : Pd[W] POWER DISSIPATION : Pd[W] 1 0.6 0.4 0.2 0.8 0.70W 0.6 0.4 0.2 0 0 0 25 50 75 100 125 0 150 25 50 75 100 125 150 TEMPARATURE[℃] TEMPARATURE[℃] Fig.20 BD1604MUV Fig.19 BD1604MVV Mount board specification Material : Glass epoxy Size : 70mm × 70mm × 1.6mm www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 9/10 2011.06 - Rev.B Technical Note BD1604MUV, BD1604MVV ●Ordering part number B D 1 Part No. BD 6 0 4 Part No. 1604 M U V - Package MUV: VQFN016V3030 MVV: SQFN016V4040 E 2 Packaging and forming specification E2: Embossed tape and reel VQFN016V3030 <Tape and Reel information> 3.0±0.1 3.0±0.1 0.5 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand ) 4 5 16 13 8 12 E2 1.4±0.1 0.4±0.1 1 3000pcs (0.22) 1.4±0.1 +0.03 0.02 −0.02 1.0MAX S C0.2 Embossed carrier tape Quantity Direction of feed 1PIN MARK 0.08 S Tape 9 0.75 +0.05 0.25 −0.04 1pin Reel (Unit : mm) Direction of feed ∗ Order quantity needs to be multiple of the minimum quantity. SQFN016V4040 <Tape and Reel information> 4.0±0.1 4.0±0.1 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand ) 1 4 5 16 13 8 12 9 2.1±0.1 0.55±0.1 E2 0.65 C0.2 1.025 2500pcs (0.22) +0.03 0.02 −0.02 1.0MAX S 2.1±0.1 Embossed carrier tape Quantity Direction of feed 1PIN MARK 0.08 S Tape +0.05 0.3 −0.04 1pin Reel (Unit : mm) www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 10/10 Direction of feed ∗ Order quantity needs to be multiple of the minimum quantity. 2011.06 - Rev.B Notice Notes No copying or reproduction of this document, in part or in whole, is permitted without the consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose of introducing ROHM's products (hereinafter "Products"). If you wish to use any such Product, please be sure to refer to the specifications, which can be obtained from ROHM upon request. Examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production. Great care was taken in ensuring the accuracy of the information specified in this document. However, should you incur any damage arising from any inaccuracy or misprint of such information, ROHM shall bear no responsibility for such damage. The technical information specified herein is intended only to show the typical functions of and examples of application circuits for the Products. ROHM does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by ROHM and other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the use of such technical information. The Products specified in this document are intended to be used with general-use electronic equipment or devices (such as audio visual equipment, office-automation equipment, communication devices, electronic appliances and amusement devices). The Products specified in this document are not designed to be radiation tolerant. While ROHM always makes efforts to enhance the quality and reliability of its Products, a Product may fail or malfunction for a variety of reasons. Please be sure to implement in your equipment using the Products safety measures to guard against the possibility of physical injury, fire or any other damage caused in the event of the failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM shall bear no responsibility whatsoever for your use of any Product outside of the prescribed scope or not in accordance with the instruction manual. The Products are not designed or manufactured to be used with any equipment, device or system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury (such as a medical instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuelcontroller or other safety device). ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes. If a Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing. If you intend to export or ship overseas any Product or technology specified herein that may be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to obtain a license or permit under the Law. Thank you for your accessing to ROHM product informations. More detail product informations and catalogs are available, please contact us. ROHM Customer Support System http://www.rohm.com/contact/ www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. R1120A