RT6030 4-CH LED Current Source Controller General Description Features The RT6030 is a current source controller, capable of driving up to 4-CH of LEDs . The part can also be used to drive an external BJT or N-MOSFET for various applications. With a wide operating voltage range from 3.8V to 13.5V, the RT6030 has the advantage of being flexible and costeffective. The RT6030 is available in an SOP-16 package. z Ordering Information Applications RT6030 z Package Type S : SOP-16 Lead Plating System G : Green (Halogen Free and Pb Free) 3.8V to 13.5V Operating Voltage z 0.8V Voltage Reference with ±2% High Accuracy z Independent Enable Control for Each Channel z Quick Transient Response z Over Temperature Protection z RoHS Compliant and Halogen Free z z z LED TV Backlight Lighting Intelligent Instruments Industrial Display Backlight Pin Configurations Note : Richtek products are : ` ments of IPC/JEDEC J-STD-020. ` (TOP VIEW) RoHS compliant and compatible with the current requireSuitable for use in SnPb or Pb-free soldering processes. Marking Information RT6030GS : Product Number RT6030 GSYMDNN YMDNN : Date Code DS6030-02 March 2011 DRI1 FB1 GND EN1 FB3 DRI3 EN3 VCC34 16 2 15 3 14 4 13 5 12 6 11 7 10 8 9 VCC12 EN2 DRI2 FB2 EN4 GND FB4 DRI4 SOP-16 www.richtek.com 1 RT6030 Typical Application Circuit VLED VCC RT6030 1 RDRI1 Q1 DRI1 VCC12 2 8 FB1 VCC34 R1 3, 11 GND RDRI2 DRI2 14 16 C34 C12 FB2 4 Chip Enable 15 7 12 R2 EN1 EN2 EN3 EN4 Q2 13 DRI3 FB3 RDRI3 6 Q3 5 R3 DRI4 9 FB4 10 RDRI4 Q4 R4 Functional Pin Description Pin No. Pin Name Pin Function st 1 DRI1 1 CH Driver Output. 2 FB1 1 CH Current Sense Voltage Feedback. 3, 11 GND Ground. 4 EN1 1st CH Chip Enable (Active High). 5 FB3 3 CH Current Sense Voltage Feedback. 6 DRI3 3 CH Driver Output. 7 EN3 3rd CH Chip Enable (Active High). 8 VCC34 CH3 and CH4 Power Supply Input. 9 DRI4 4 CH Driver Output. 10 FB4 4 CH Current Sense Voltage Feedback. 12 EN4 4 CH Chip Enable (Active High). 13 FB2 2 14 DRI2 st rd rd th th th nd CH Current Sense Voltage Feedback. nd CH Driver Output. nd CH Chip Enable (Active High). 2 15 EN2 2 16 VCC12 CH1 and CH2 Power Supply Input. www.richtek.com 2 DS6030-02 March 2011 RT6030 Function Block Diagram VCC12 EN1 VREF Voltage 0.8V + EA - DRI1 FB1 EN2 VREF Voltage 0.8V + EA - FB2 VCC34 EN3 DRI2 VREF Voltage 0.8V + EA - DRI3 FB3 EN4 GND DS6030-02 March 2011 VREF Voltage 0.8V + EA - DRI4 FB4 www.richtek.com 3 RT6030 Absolute Maximum Ratings z z z z z z z z (Note 1) VCC12, VCC34 ------------------------------------------------------------------------------------------------------------ 15V All Other Inputs ------------------------------------------------------------------------------------------------------------ 7V Power Dissipation, PD @ TA = 25°C SOP-16 ---------------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) SOP-16, θJA ---------------------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM -------------------------------------------------------------------------------------------------------------------------MM ---------------------------------------------------------------------------------------------------------------------------- Recommended Operating Conditions z z z z 1.053W 95°C/W 260°C 150°C −65°C to 150°C 1.5kV 150V (Note 4) Supply Input Voltage, VCC12 , VCC34 ----------------------------------------------------------------------------------- 3.8V to 13.5V Chip Enable Voltage, EN1, EN2, EN3, EN4 ------------------------------------------------------------------------ 0V to 5.5V Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VCC12 = 5V/12V, VCC34 = 5V/12V, TA = 25°C, unless otherwise specified) Parameter Under Voltage Lockout Threshold Under Voltage Lockout Hysteresis Symbol Test Conditions Min Typ Max Unit VUVLO VCC12 and VCC34 Rising 3.15 3.4 3.65 V ΔVUVLO VCC12 and VCC34 Falling 0.1 0.2 0.3 V VCC12 and VCC34 = 12V -- 0.6 1.6 mA VCC12 and VCC34 Supply Current Driver Source Current ISR VCC12 and VCC34 = 12V VDRI1 to VDRI4 = 6V 5 -- -- mA Driver Sink Current ISK VCC12 and VCC34 = 12V VDRI1 to VDRI4 = 6V 5 -- -- mA VCC12 and VCC34 = 12V VDRI1 to VDRI4 = 5V 0.784 0.8 0.816 V VCC12 and VCC34 = 4.5V to 13.5V -- 3 6 mV VCC12 and VCC34 = 12V, No Load -- 70 -- dB Reference Voltage (VFB1 to VFB4) Reference Line Regulation (VFB1 to VFB4) Amplifier Voltage Gain Chip Enable EN Rising Threshold VEN VCC12 and VCC34 = 12V -- 0.7 -- V EN Hysteresis ΔVEN VCC12 and VCC34 = 12V VCC12 and VCC34 = 12V VEN1 to VEN4 = 0V -- 30 -- mV -- -- 10 μA Standby Current www.richtek.com 4 DS6030-02 March 2011 RT6030 Note 1. Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. θJA is measured in natural convection at TA = 25°C on a low-effective thermal conductivity test board of JEDEC 51-3 thermal measurement standard. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. DS6030-02 March 2011 www.richtek.com 5 RT6030 Typical Operating Characteristics Supply Current vs. VCC12/VCC34 Input Voltage 1.0 1.0 0.9 0.9 0.8 0.8 Supply Current (mA) Standby Current (µA)1 Standby Current vs. VCC12/VCC34 Input Voltage 0.7 0.6 0.5 0.4 0.3 ICC12 ICC34 0.2 0.1 3.5 5 6.5 8 9.5 11 ICC12 ICC34 0.6 0.5 0.4 0.3 0.2 0.1 VEN1 to VEN4 = 0V 0.0 0.7 12.5 VEN1 to VEN4 = 3V 0.0 14 3.5 5 6.5 8 9.5 11 12.5 14 VCC12/VCC34 Input Voltage (V) VCC12/VCC34 Input Voltage (V) Supply Current vs. Temperature EN Threshold Voltage vs. VCC12 Input Voltage 1.0 1.0 EN Threshold Voltage (V) Supply Current (mA) 0.9 0.8 0.7 ICC12 ICC34 0.6 0.5 0.4 0.3 0.2 0.1 0.9 0.8 0.7 0.6 0.5 VEN1 to VEN4 = 3V 0.0 0.4 -50 -25 0 25 50 75 100 125 3.5 5 EN Threshold Voltage vs. Temperature 8 9.5 11 12.5 14 Feedback Reference Voltage vs. VCC12 Input Voltage Feedback Reference Voltage (V) 1.0 EN Threshold Voltage (V) 6.5 VCC12 Input Voltage (V) Temperature (°C) 0.9 0.8 0.7 0.6 0.5 VCC12 = 12V 0.4 0.820 0.815 0.810 0.805 0.800 0.795 0.790 0.785 VEN1 = 3V 0.780 -50 -25 0 25 50 Temperature (°C) www.richtek.com 6 75 100 125 3.5 5 6.5 8 9.5 11 12.5 14 VCC12 Input Voltage (V) DS6030-02 March 2011 RT6030 DRI Source Current vs. DRI1 Voltage Feedback Reference Voltage vs. Temperature 55 53 DRI Source Current (mA) Feedback Reference Voltage (V) 0.82 0.81 0.80 0.79 0.78 0.77 51 49 47 45 43 41 39 37 VCC12 = 12V 0.76 VCC12 = 12V, VFB1 = 0.6V, VEN1 = 3V 35 -50 -25 0 25 50 75 100 125 0 1 2 Temperature (°C) 4 5 6 7 DRI1 Voltage (V) DRI Source Current vs. Temperature DRI Sink Current vs. DRI1 Voltage 70 25 60 DRI Sink Current (mA) DRI Source Current (mA) 3 50 40 30 20 20 15 10 5 10 VCC12 = 12V, VFB1 = 0.6V, VDRI1 = 6V VCC12 = 12V, VFB1 = 1V, VEN1 = 3V 0 0 -50 -25 0 25 50 75 100 0 125 1 2 3 4 5 6 7 DRI1 Voltage (V) Temperature (°C) LED Current vs. PWM Duty PWM Dimming From EN 180 LED Current (mA) 160 VEN (5V/Div) 140 120 100 VFB1 (500mV/Div) ILED1 ILED2 ILED3 ILED4 80 60 VLED (2V/Div) I LED (100mA/Div) 40 VCC1 = VCC2 = 12V, RSET = 5.1Ω, LED = 8ea, EN = 0 to 5V/250Hz 20 0 0 20 40 60 PWM Duty (%) DS6030-02 March 2011 80 100 VCC12 = 12V, R1 = 5.1Ω, LED = 3V Time (5ms/Div) www.richtek.com 7 RT6030 Applications Information The RT6030 is a 4-CH LED current source controller. This device can also drive an external BJT or N-MOSFET for various applications. Refer to topology in Typical Application Circuit for more details. Capacitors Selection Careful selection of the external capacitors for the RT6030 is highly recommended in order to maintain high stability and performance. An input capacitor with minimum 1μF must be connected between VCC and ground. The capacitor improves the supply voltage stability for proper operation. Chip Enable Operation Pull the EN pin low to drive the device into shutdown mode. During shutdown mode, the standby current drops to 10mA(MAX). Drive the EN pin high to turn on the device again. To control LED brightness, the RT6030 can perform dimming function by applying a PWM signal to the EN pin. The average LED current is proportional to the PWM signal duty cycle. To obtain correct dimming, the magnitude of the PWM signal should be higher than the threshold voltage of the EN pin. MOSFET Selection The RT6030 is designed to drive external N-MOSFET pass element. MOSFET selection criteria include threshold voltage, VGS (VTH), maximum continuous drain current, ID, on resistance, RDS(ON) ,maximum drain-to-source voltage, VDS, and package thermal resistance, θJA. The most critical specification is the MOSFET RDS(ON). RDS(ON) can be calculated from the following formula : RDS(ON) (V − VOUT ) = IN IO For example, the MOSFET operates up to 2A when the input voltage is 1.5V and set the output voltage as 1.2V. Then, R DS(ON) = (1.5V − 1.2V) / 2A = 150mΩ. The MOSFET's RDS(ON) must be lower than 150mΩ. Philip PHD3055E MOSFET with an RDS(ON) of 120mΩ (typ.) is a suitable solution. The power dissipation is calculated as : PD = (VIN − VOUT ) x ILOAD www.richtek.com 8 The thermal resistance from junction to ambient is : (T − TA ) θJA = J PD In this example, PD = (1.5V−1.2V) x 2A = 0.6W. The PHD3055E's θJA is 75°C/W for its D-PAK package, which translates to a 45°C temperature rise above ambient. The package provides exposed backsides that directly transfer heat to the PCB board. LED Current Setting The RT6030 maintains an internal reference voltage of 0.8V. As shown in Typical Application Circuit, the LED current can be set accordingly via the Rx (x = 1, 2, 3, 4) resistor. 0.8 ILEDx = (A) Rx NPN Transistor Selection The RT6030 drives the external NPN transistor via the DRIx pin (source Base current IB). NPN transistor selection criteria include DC current gain, hFE, threshold voltage, VBE, collector emitter voltage, VCE, maximum continuous collector current, IC, and package thermal resistance, θJA. Thermal Considerations For continuous operation, do not exceed absolute maximum junction temperature. The maximum power dissipation depends on the thermal resistance of the IC package, PCB layout, rate of surrounding airflow, and difference between junction and ambient temperature. The maximum power dissipation can be calculated by the following formula : PD(MAX) = (TJ(MAX) − TA) / θJA where TJ(MAX) is the maximum junction temperature, TA is the ambient temperature, and θJA is the junction to ambient thermal resistance. For recommended operating condition specifications of the RT6030, the maximum junction temperature is 125°C and TA is the ambient temperature. The junction to ambient thermal resistance, θ JA , is layout dependent. For SOP-16 packages, the thermal resistance, θ JA , is 95°C/W on a standard JEDEC 51-3 single-layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by the following formula : DS6030-02 March 2011 RT6030 PD(MAX) = (125°C − 25°C) / (95°C/W) = 1.053W for SOP-16 package Layout Considerations There are three critical layout considerations. Maximum Power Dissipation (W)1 The maximum power dissipation depends on the operating ambient temperature for fixed T J(MAX) and thermal resistance, θJA. For the RT6030 package, the derating curve in Figure 1 allows the designer to see the effect of rising ambient temperature on the maximum power dissipation. 1.10 Single-Layer PCB 1.00 0.90 0.80 0.70 0.60 ` First the current setting resistor should be placed as close as possible to the RT6030 to prevent any noise coupling. ` Second of all CIN and COUT should be placed near the RT6030 for good performance. ` Last of all, proper copper area for the pass element should be acknowledged. Pass elements operating under high power situations can result in abnormally junction temperature. In addition to the package thermal resistance limit, the copper area should be increased accordingly to improve the power dissipation. 0.50 0.40 0.30 0.20 0.10 0.00 0 25 50 75 100 125 Ambient Temperature (°C) Figure 1. Derating Curve for RT6030 Package VLED VLED FBx node copper area should be minimized and kept far away from noise sources. VLED CIN should be placed near the IC for improve performance. VCC C12 RDRI1 DRI1 FB1 GND R1 EN1 R2 FB3 DRI3 RDRI2 EN3 VCC34 VCC 16 2 15 3 14 4 13 5 12 6 11 7 10 8 9 VCC12 EN2 DRI2 FB2 EN4 GND FB4 DRI4 C34 GND GND RDRI3 VLED R3 R4 RDRI4 The GND plane should be connected to a strong ground plane for heat sinking and noise protection. Figure 2. PCB Layout Guide DS6030-02 March 2011 www.richtek.com 9 RT6030 Outline Dimension H A M B J F C I D Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 9.804 10.008 0.386 0.394 B 3.810 3.988 0.150 0.157 C 1.346 1.753 0.053 0.069 D 0.330 0.508 0.013 0.020 F 1.194 1.346 0.047 0.053 H 0.178 0.254 0.007 0.010 I 0.102 0.254 0.004 0.010 J 5.791 6.198 0.228 0.244 M 0.406 1.270 0.016 0.050 16–Lead SOP Plastic Package Richtek Technology Corporation Richtek Technology Corporation Headquarter Taipei Office (Marketing) 5F, No. 20, Taiyuen Street, Chupei City 5F, No. 95, Minchiuan Road, Hsintien City Hsinchu, Taiwan, R.O.C. Taipei County, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Tel: (8862)86672399 Fax: (8862)86672377 Email: [email protected] Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit design, specification or other related things if necessary without notice at any time. No third party intellectual property infringement of the applications should be guaranteed by users when integrating Richtek products into any application. No legal responsibility for any said applications is assumed by Richtek. www.richtek.com 10 DS6030-02 March 2011