THL6516_Rev.1.01_E THL6516 4 channels LED Driver Description Features THL6516 is a 4 channels LED driver. THL6516 has a built-in boost converter, since back light system can consist of 1 chip. Soft start / Over current protection / Vout short circuit protection / Under voltage lock out protection / Over voltage protection / LED short protection / LED open protection / Thermal shut down are built in. Mounted area is reducible by 16-pin QFN. ・Input voltage range : 4.2V - 24V ・Boost converter Maximum output voltage : 40V Switching frequency range : 500kHz - 2MHz ・LED driver Up to 80mA per channel Current accuracy : +/-3% Current matching : +/-1.5% ・PWM dimming control : 100Hz - 30kHz ・Protection circuit Soft start Over current protection Vout short circuit protection Under voltage lock out protection Over voltage protection LED short protection LED open protection Thermal shut down ・3mm x 3mm QFN 16pin package Application ･Mobile phone display backlight ・Car Navigator display backlight ･Laptop/Netbook/Tablet PC display backlight Pin Configuration Block Diagram OUT4 OUT3 OUT2 OUT1 16 15 14 13 VIN AGND 1 PC VCC EN 12 OVP LX UVLO Boost PGND Protect circuit OVP OSC PC 2 11 SS PGND 4 Exposed Thermal Pad REXT RT OUT1 PWM (Top view) 3 10 17 GNDEXP RT 4 9 5 6 7 8 PWM EN VCC LX OUT2 PGND LX OSC OSC 1/9 OUT3 OUT4 AGND Copyright© 2013 THine Electronics, Inc. All rights reserved. Current driver REXT THine Electronics, Inc. THL6516_Rev.1.01_E Absolute Maximum Ratings Parameter Symbol VCC VH1 VH2 VH3 Pd Tj Tstg VCC voltage LX voltage OUT[4:1] voltage EN, PWM voltage Power dissipation Junction temperature (*1) Storage temperature range Rating 27 45 43 27 2.33 -40 to +125 -55 to +150 Units V V V V W o C o C *1. The operating temperature range should perform a thermal design, after consulting the thermal characteristic. Please use it in the range which does not exceed junction temperature. Recommended Operating Conditions Parameter Min 4.2 500 3 0.1 VCC voltage OUT[4:1] voltage Switching frequency LED output current PWM dimming control Copyright© 2013 THine Electronics, Inc. All rights reserved. 2/9 Typ - Max 24 40 2000 80 30 Units V V kHz mA kHz THine Electronics, Inc. THL6516_Rev.1.01_E Pin Description Number 1 Name AGND 2 PC 3 REXT 4 RT 5 PWM 6 EN 7 VCC 8, 9 LX 10, 11 PGND 12 OVP Over voltage protection input pin. OUT1 OUT2 OUT3 OUT4 LED current sink regulation input pins. These pins are the constant current output. The constant current is determined by REXT resistor. Back side. GND EXP should be soldered to GND to improve the thermal characteristics. 13 15 17 14 16 GND EXP Function Analog ground. Boost converter error amplifier output pin. LED current set pin. Switching frequency control pin. PWM dimming control input pin. Enable pin. Input supply voltage pin. Boost converter switching output pins. Power ground. Description Analog ground of LED driver. This pin is the boost converter error amplifier output. Please connect resistance and capacitor to GND for phase compensation. LED current is set by the value of the external resistor. This pin is controlled switching frequency by external resistance. This pin is control input to LED dimming. If low level voltage is impressed, the LED driver is shutdown. Power supply pin. These pins are switching output of boost converter. Power ground pins of boost converter. This pin is the over voltage protection circuit setting input of the boost converter for LED driver. This pin is controlled by external resistance. Power Dissipation Power Dissipation [mW] 2500 2000 1500 1000 500 0 -40 -20 0 20 40 60 80 100 120 140 Operating Temperature [ ℃ ] Copyright© 2013 THine Electronics, Inc. All rights reserved. 3/9 THine Electronics, Inc. THL6516_Rev.1.01_E Electrical Characteristics Parameter （at VCC＝12V , Ta=25℃, unless otherwise noted） Symbol Input quiescent Current 1 Icc1 Input quiescent Current 2 Icc2 Standby current Ist UVLO threshold voltage Vuvlo UVLO hysteresis voltage dVuvloh PWM/EN pull down resistance PWM/EN input high voltage PWM/EN input low voltage PWM/EN minimum pulse Boost converter switching frequency Maximum duty cycle Vpc=0V(No switching) EN>1.9V Vpc=2V(Switching), EN>1.9V EN<0.8V VCC rising Min Typ Max Units - 1 1.5 mA - 2 3 mA - - 10 uA - 3.6 - V - 0.4 - V Rpwm_en - 800 - kΩ Vpwm_h 1.9 - - V Vpwm_l - - 0.8 V Tmin_pulse - 2 - us Fosc Rrt=51kΩ 0.8 1 1.2 MHz Dmax Rrt=51kΩ, Vpc=2V 91 93 95 % - 0.2 0.6 Ω LX ON-resistance Ron Minimum ON-time Ton_min LX current limit Test Conditions Rrt=51kΩ Ilim 155 - nsec 2 - A 3 - 80 mA - - 3 uA LED current per channel Iled_max OUTx pin leakage current Ileak OUTx pin regulation threshold Vout Rrext=4.75kΩ - 0.56 - V LED current accuracy Iled Rrext=4.75kΩ 19.4 20.0 20.6 mA LED current matching Dled - - 1.5 % Over voltage protection threshold Vovp 1.1 1.2 1.3 V Vscp - - 75 mV Vled_s 7 - 9.5 V OVP short circuit threshold LED short protection protection Vpwm_h>1.9V 1.7 VOUT=36V Vpwm_l<0.8V Rrext=4.75kΩ (Imax-Imin)/Iave Copyright© 2013 THine Electronics, Inc. All rights reserved. 4/9 , THine Electronics, Inc. THL6516_Rev.1.01_E voltage and output voltage becomes the largest at the Function moment of Under voltage lock out protection (UVLO) Input voltage / Output voltage being canceled. If the difference of input voltage and output voltage In this condition, most much current flows from an input. becomes large, the ON duty cycle (Don) will become When input voltage is inputted slowly, the over current small. Depending on the conditions of input and output protection circuit is operated for the above-mentioned voltage, the pulse width below the minimum pulse width, reason. In that case, please input into VCC after inputting 155nsec is needed. In this case, a pulse is skipped and EN input or PWM input. In inputting into VCC, please frequency is decreased. Please decide the input and use the conditions that it does not become an over output voltage condition with considering a maximum current. duty cycle and the minimum pulse width. Moreover, if the input voltage is unstable, please connect R-C filter to the input line. When input voltage rises Boost converter steeply, by the capacitive coupling of the inside transistor The boost converter for an LED drive is built in. The of IC, excess voltage may be built over the low resisting voltage of an LED constant current output OUTn pin is pressure element inside IC, and it may become a cause of feedback, and the suitable voltage for the anode of LED failure. If input voltage rises sharply, excess voltage is is supplied. The oscillating frequency of a boost added to a low resisting pressure element by the converter is determined by the following formula in 2 capacitive coupling of the inside transistor of IC. MHz from 500 Hz with the oscillating frequency setting Thereby, it may become a cause of failure. It by RT pin. recommends inserting the filter (Fig. 1) of 10ohm / 1uF fosc[ MHz ] in a VCC pin. 51 10 3 RRT VIN Enable The standby function is carried. When a low level signal is inputted into EN pin, it will be in a standby state. And 10Ω 1uF a boost converter and an LED constant current output are VCC suspended. The consumed current is set to less than 10uA in a standby state. EN does not have restriction of Fig. 1 Filter setup of VCC input an input sequence. If inputted into EN before the input of VCC, there is no problem. <<Notes>> This product contains the over circuit in order to protect current protection destruction of IC from the PWM dimming output abnormality of a boost converter. Please refer to The dimming function is carried. It is possible to control Over current protection (OCP) for details. After a ON/OFF of the constant current output for LED by power supply is inputted, the voltage difference of input inputting in a PWM signal. An LED output becomes Copyright© 2013 THine Electronics, Inc. All rights reserved. 5/9 THine Electronics, Inc. THL6516_Rev.1.01_E active when a PWM signal is a high level. Please input a dimming signal in 30kHz from 100Hz. The minimum Protection circuits duty cycle DPWMmin which can be set up by a PWM Under voltage lock out protection (UVLO) dimming function is determined by the following The UVLO function is carried in order to prevent formula from PWM minimum pulse width and the malfunction in the state where input voltage is low. A frequency fPWM of PWM. boost converter and an LED constant current output are suspended to the power supply voltage which can carry DPWM min [%] 2[ sec] f PWM [ MHz ] 100 out operational stability. UVLO is released by more than 3.6V input voltage. And a boost converter carries out When not use a dimming function, please input the LEDs constant current drive, after starting soft start signal of a high level to PWM pin. If a dimming signal operation. which is less than 100Hz is inputted, a boost converter is stopped and it performs the same operation as EN. PWM does not have restriction of an input sequence. If inputted Soft start (SS) into PWM before the input of VCC, there is no problem. The boost converter carries the soft start function in order to prevent the rush current at a start up. This function is to raise output voltage slowly. It is because LED constant current output setup overshooting and rush current occur when input voltage LED current is determined by resistance connected to a is inputted. REXT pin. Please use it according to the following formula in the range from, 3mA/ch to 80 mA/ch. Over voltage protection (OVP) 95 I LED [mA] 1000 R EXT Over voltage protection is built in. If LED is disconnecting, the output voltage of a boost converter is stopped and destruction of IC is prevented. In consideration of the threshold voltage of an OVP pin, LED constant current output OVP sets up in the range below a boost converter output. Please connect LED constant current output OUT1-4 to VOVP V 1.2 (1 the cathode of LED. The constant current is supplied to LEDs decided by REXT. If the current needs more than R2 ) R1 Boost converter output 80mA, please connect each output pin. If there is an LED output which is not used, please connect with GND. R2 Over voltage protection pin Fig. 2 Copyright© 2013 THine Electronics, Inc. All rights reserved. 6/9 R1 Over voltage protection setup THine Electronics, Inc. THL6516_Rev.1.01_E Over current protection (OCP) In order to restrict the over current by the abnormalities Normal Operation of load, etc., the over-current protection circuit is built in. Over current detection of pulse-by-pulse system is adopted. An output transistor is turned off if the current Check if any working channel voltage > 7V which flows into an output transistor reaches boost No Yes converter limit current (Ilim). The output transistor operates again in reset time in IC after that. An over Turn off this channel current protection circuit detects the peak current of an No inductor. Input and output voltage and not only LED If all channels voltage Yes constant current but ripple current is taken into Turn off all channels and Reset the turn-off status (Turn on allthe channels) consideration. Fig. 3 LED short protection circuit function Short circuits protection (SCP) If the output of a boost converter connects with GND and, OVP pin is arrived at less than 75 mV, short circuits LED open protection protection is carried out. In that case, operation of a When an LED constant current output opens, the opened boost converter is stopped. If a short state is canceled, it LED constant current output is separated from the will return to normal operation. feedback loop, and stops. The other LED constant current output connected continues normal operation. If an open state is canceled, it will return to normal LED short protection operation. If all the LED constant current outputs If LED line was shorted and the LED constant current become open, the output voltage of a boost converter output OUTn reaches more than 7V, an LED constant will be raised and the over voltage protection will current output will be suspended. Even if the short state operate. is canceled, an LED constant current output holds a halt condition. The LED constant current output which does not act as short continues normal operation. Short circuit Thermal shut down (TSD) of all the LED constant current outputs will stop In order to prevent destruction by heat, the thermal operation of a boost converter. If the short state is shutdown circuit is built in. If the junction temperature canceled, it returns to normal operation. (Fig. 3) Tj is 125oC or more, the thermal shutdown circuit will operate and it will stop switching operation. Moreover, the hysteresis of a thermal shutdown circuit is 15 oC. If Tj falls, output voltage will return. Copyright© 2013 THine Electronics, Inc. All rights reserved. 7/9 THine Electronics, Inc. THL6516_Rev.1.01_E Package Dimensions QFN 16-pin Recommend connecting Back Exposed Pad with GND for a thermal characteristic improvement. Copyright© 2013 THine Electronics, Inc. All rights reserved. 8/9 THine Electronics, Inc. THL6516_Rev.1.01_E Notices and Requests 1. The product specifications described in this material are subject to change without prior notice. 2. The circuit diagrams described in this material are examples of the application which may not always apply to the customer’s design. We are not responsible for possible errors and omissions in this material. Please note if errors or omissions should be found in this material, we may not be able to correct them immediately. 3. This material contains our copyright, know-how or other proprietary. Copying or disclosing to third parties the contents of this material without our prior permission is prohibited. 4. Note that if infringement of any third party's industrial ownership should occur by using this product, we will be exempted from the responsibility unless it directly relates to the production process or functions of the product. 5. This product is presumed to be used for general electric equipment, not for the applications which require very high reliability (including medical equipment directly concerning people's life, aerospace equipment, or nuclear control equipment). Also, when using this product for the equipment concerned with the control and safety of the transportation means, the traffic signal equipment, or various Types of safety equipment, please do it after applying appropriate measures to the product. 6. Despite our utmost efforts to improve the quality and reliability of the product, faults will occur with a certain small probability, which is inevitable to a semi-conductor product. Therefore, you are encouraged to have sufficiently redundant or error preventive design applied to the use of the product so as not to have our product cause any social or public damage. 7. Please note that this product is not designed to be radiation-proof. 8. Customers are asked, if required, to judge by themselves if this product falls under the category of strategic goods under the Foreign Exchange and Foreign Trade Control Law. 9. The product or peripheral parts may be damaged by a surge in voltage over the absolute maximum ratings or malfunction, if pins of the product are shorted by such as foreign substance. The damageｓ may cause a smoking and ignition. Therefore, you are encouraged to implement safety measures by adding protection devices, such as fuses. THine Electronics, Inc. [email protected] Copyright© 2013 THine Electronics, Inc. All rights reserved. 9/9 THine Electronics, Inc.