CAT4104 700 mA Quad Channel Constant Current LED Driver FEATURES DESCRIPTION The CAT4104 provides four matched low dropout current sinks to drive high-brightness LED strings up to 175 mA per channel. The LED channel current is set by an external resistor connected to the RSET pin. The LED pins are compatible with high voltage up to 25 V supporting applications with long strings of LEDs. 4 matched LED current sinks up to 175 mA Up to 25 V operation on LED pins Low dropout Current Source (0.4 V at 175 mA) LED current set by external resistor High frequency PWM dimming via EN/PWM “Zero” current Shutdown mode Thermal shutdown protection RoHS-compliant TDFN 8-Pad 2 x 3 mm and SOIC 8-Lead packages The EN/PWM logic input supports the device enable and high frequency external Pulse Width Modulation (PWM) dimming control. Thermal shutdown protection is incorporated in the device to disable the LED outputs whenever the die temperature exceeds 150ºC. APPLICATIONS Automotive Lighting General and Architectural Lighting LCD backlight The device is available in the 8-pad TDFN 2 mm x 3 mm package and the SOIC 8-Lead 150 mil wide package. ORDERING INFORMATION Part Number Package Quantity per Reel Package Marking CAT4104V-GT3 SOIC-8* 3,000 CAT4104V CAT4104VP2-GT3 TDFN-8* 3,000 HC * Lead Finish is NiPdAu PIN CONFIGURATION TYPICAL APPLICATION CIRCUIT VCC 3 V to 25 V TDFN 8-Pad (Top View) LED1 1 8 RSET LED2 2 7 VIN LED3 3 6 EN/PWM LEDs LED4 4 VIN 5V 5 GND VIN CAT4104 LED1 LED2 OFF ON SOIC 8-Lead (Top View) LED1 1 8 RSET LED2 2 7 VIN LED3 3 6 EN/PWM LED4 4 5 GND © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice EN/PWM LED3 LED4 RSET R1 768 Ω 1 GND 175 mA Doc. No. MD-5041 Rev. B CAT4104 ABSOLUTE MAXIMUM RATINGS Parameter Rating Unit VIN, RSET, EN/PWM Voltages -0.3 to 6 V LED1, LED2, LED3, LED4 Voltages -0.3 to 25 V Storage Temperature Range -65 to +160 °C Junction Temperature Range -40 to +150 °C 300 °C Lead Temperature RECOMMENDED OPERATING CONDITIONS Parameter Rating VIN Voltage applied to LED1 to LED4, outputs off Voltage applied to LED1 to LED4, outputs on Unit 3.0 to 5.5 V up to 25 V up to 6* V Ambient Temperature Range -40 to +85 °C ILED per LED pin 10 to 175 mA * Keeping LEDx pin voltage below 6 V in operation is recommended to minimize thermal dissipation in the package. Typical application circuit with external components is shown on page 1. ELECTRICAL OPERATING CHARACTERISTICS Min and Max values are over the recommended operating conditions unless specified otherwise. Typical values are at VIN = 5.0 V, TAMB = 25°C Symbol Name Conditions ILED-ACC LED Current Accuracy ILEDNOM − ILED ILEDNOM ILED-DEV LED Channel Matching ILED − ILEDAVG , note 1 ILED VDOUT Dropout Voltage ILED = 175 mA VRSET RSET Pin Voltage IQ Quiescent Current No LED, RSET = Float No LED, RSET = 770 Ω IQSHDN Shutdown Current VEN = 0V REN/PWM VHI VLO Min Max ±2 -5 ±1 1.2 Units % +5 400 1.17 EN/PWM Pin • Internal pull-down resistance • Logic High Level • Logic Low Level Typ % mV 1.23 0.6 6 V mA mA 1 µA 0.4 kΩ V V 200 1.3 TSD Thermal Shutdown 150 °C THYS Thermal Hysteresis 20 °C ILED/IRSET VUVLO RSET to LED Current gain ratio 25 mA LED current Undervoltage lockout (UVLO) threshold 100 2.0 V Note 1: Min and Max values are tested for ILED = 50 mA, VIN = 3.5 V, VLEDx = 0.4 V, TAMB = 25°C. Doc. No. MD-5041 Rev. B 2 © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice CAT4104 RECOMMENDED EN/PWM TIMING Min and Max values are over the recommended operating conditions unless specified otherwise. Typical values are at VIN = 5.0 V, TAMB = 25°C Symbol Name Conditions TPS Turn-On time, EN/PWM rising to ILED from shutdown ILED = 175 mA ILED = 80 mA 1.5 1.3 μs TP1 Turn-On time, EN/PWM rising to ILED ILED = 175 mA 600 ns TP2 Turn-Off time, EN/PWM falling to ILED ILED = 175 mA ILED = 80 mA 400 300 ns TR LED rise time ILED = 175 mA ILED = 80 mA 700 440 ns TF LED fall time ILED = 175 mA ILED = 80 mA 360 320 ns TLO EN/PWM low time 1 μs THI EN/PWM high time 5 μs TPWRDWN Min EN/PWM low time to shutdown delay Typ 4 Max 8 Units ms TPWRDWN THI TLO EN/PWM SHUTDOWN POWERDOWN TP2 TPS TF TP1 ILED = TR SHUTDOWN 0 mA 1.2 V x 100 RSET 90% LED CURRENT SHUTDOWN 0 mA 50% 50% 10% 0 mA QUIESCENT CURRENT SHUTDOWN 0 mA SHUTDOWN 0 mA Figure 1. CAT4104 EN/PWM Timing EN/PWM OPERATION The EN/PWM pin has two primary functions. One function enables and disables the device. The other function turns the LED channels on and off for PWM dimming control. The device has a very fast turn-on time (from EN/PWM rising to LED on) and allows “instant on” when dimming LED using a PWM signal. When performing a combination of low frequencies and small duty cycles, the device may enter shutdown mode. This has no effect on the dimming accuracy, because the turn-on time TPS is very short, in the range of 1 µs. To ensure that PWM pulses are recognized, pulse width low time TLO should be longer than 1 µs. The CAT4104 enters a “zero current” shutdown mode after a 4 ms delay (typical) when EN/PWM is held low. Accurate linear dimming is compatible with PWM frequencies from 100 Hz to 5 kHz for PWM duty cycle down to 1%. PWM frequencies up to 50 kHz can be supported for duty cycles greater than 10%. © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice 3 Doc. No. MD-5041 Rev. B CAT4104 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 5 V, VCC = 5 V, LED forward voltage = 3.5 V, CIN = 1 μF, TAMB = 25°C unless otherwise specified. Quiescent Current vs. Input Voltage (RSET Open) Quiescent Current vs. RSET Current 8.0 QUIESCENT CURRENT [mA] QUIESCENT CURRENT [mA] 1.2 No Load 1.0 0.8 0.6 3.0 3.5 4.0 4.5 5.0 INPUT VOLTAGE [V] 2.0 0.0 5.5 0.5 1.0 1.5 RSET CURRENT [mA] 2.0 LED Dropout vs. LED Pin Voltage Quiescent Current vs. Input Voltage (Full Load) 200 7.0 Full Load LED CURRENT [mA] QUIESCENT CURRENT [mA] 4.0 0.0 0.4 6.5 6.0 5.5 160 120 80 40 0 5.0 3.0 3.5 4.0 4.5 5.0 INPUT VOLTAGE [V] 0.0 5.5 LED Line Regulation 200 200 160 160 120 80 40 1.0 120 80 40 0 0 3.0 Doc. No. MD-5041 Rev. B 0.2 0.4 0.6 0.8 LED PIN VOLTAGE [V] LED Current Change vs. Temperature LED CURRENT [mA] LED CURRENT [mA] 6.0 3.5 4.0 4.5 VIN [V] 5.0 -40 5.5 4 0 40 80 TEMPERATURE [ºC] 120 © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice CAT4104 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 5 V, VCC = 5 V, LED forward voltage = 3.5 V, CIN = 1 μF, TAMB = 25°C unless otherwise specified. LED Current vs. LED Pin Voltage LED Current vs. RSET Resistor 200 LED CURRENT [mA] LED CURRENT [mA] 1000 100 120 80 40 0 10 0.1 1.0 RSET [kΩ] 0 10.0 1 2 3 4 5 6 LED PIN VOLTAGE [V] RSET Pin Voltage vs. Temperature RSET Pin Voltage vs. Input Voltage 1.30 RSET VOLTAGE [V] 1.30 RSET VOLTAGE [V] 160 1.25 1.20 1.15 1.25 1.20 1.15 1.10 1.10 3.0 3.5 4.0 4.5 5.0 INPUT VOLTAGE [V] -40 5.5 0 40 80 TEMPERATURE [ºC] 120 LED Off Current vs. LED pin Voltage LED OFF CURRENT [µA] . 1.0 0.8 0.6 -40ºC 0.4 +25ºC 0.2 +125ºC 0.0 0 5 10 15 20 25 30 LED PIN VOLTAGE [V] © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice 5 Doc. No. MD-5041 Rev. B CAT4104 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 5 V, VCC = 5 V, LED forward voltage = 3.5 V, CIN = 1 μF, TAMB = 25°C unless otherwise specified. EN/PWM Pull-down Current vs. VEN/PWM EN/PWM Threshold vs. VIN 1.4 ENABLE THRESHOLD [V] ENABLE CURRENT [uA] 25 20 15 10 5 0 1.2 -40ºC 25ºC 1.0 0.8 85ºC 0.6 0.4 0 1 2 3 4 ENABLE VOLTAGE [V] 5 3.0 3.5 4.0 4.5 5.0 INPUT VOLTAGE [V] 5.5 Power Down Power Up from Shutdown PWM 200 Hz, 1% Duty Cycle Doc. No. MD-5041 Rev. B 6 © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice CAT4104 PIN DESCRIPTIONS Name LED1 Pin SOIC 8-Lead 1 Pin TDFN 8-Lead 1 Function LED1 cathode terminal LED2 2 2 LED2 cathode terminal LED3 3 3 LED3 cathode terminal LED4 4 4 LED4 cathode terminal GND 5 5 and TAB EN/PWM 6 6 Device enable input and PWM control VIN 7 7 Device supply pin RSET 8 8 LED current set pin for the LED channels Ground reference PIN FUNCTION VIN is the supply pin for the device. A small 0.1 μF ceramic bypass capacitor is optional for noisy environments. Whenever the input supply falls below the under-voltage threshold, all LED channels are automatically disabled. RSET pin is connected to an external resistor to set the LED channel current. The ground side of the external resistor should be star connected to the GND of the PCB. The pin source current mirrors the current to the LED sinks. The voltage at this pin is regulated to 1.2 V. EN/PWM is the enable and one wire dimming input for all LED channels. Guaranteed levels of logic high and logic low are set at 1.3 V and 0.4 V respetively. When EN/PWM is initially taken high, the device becomes enabled and all LED currents are set at a gain of 100 times the current in RSET. To place the device into zero current shutdown mode, the EN/PWM pin must be held low for 4 ms typical. GND is the ground reference for the device. The pin must be connected to the ground plane on the PCB. TAB (TDFN 8-Lead Only) is the exposed pad underneath the package. For best thermal performance, the tab should be soldered to the PCB and connected to the ground plane. LED1 to LED4 provide individual regulated currents for each of the LED cathodes. There pins enter a high impedance zero current state whenver the device is placed in shutdown mode. © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice 7 Doc. No. MD-5041 Rev. B CAT4104 BLOCK DIAGRAM VIN LED1 LED2 LED3 LED4 VIN EN/PWM 1.2 V Reference RSET 4 Current Sink Regulators Current Setting GND Figure 2. CAT4104 Functional Block Diagram BASIC OPERATION The CAT4104 has four tightly matched current sinks to regulate LED current in each channel. The LED current in the four channels is mirrored from the current flowing through the RSET pin according to the following formula: 1.2 V ILED ≅ 100 × R SET Table 1 shows standard resistor values for RSET and the corresponding LED current. Tight current regulation for all channels is possible over a wide range of input voltages and LED voltages due to independent current sensing circuitry on each channel. Table 1. RSET Resistor Settings For applications requiring more than 175 mA current, LED channels can be tied together to sink up to a total of 700 mA from the one device. LED Current [mA] RSET [kΩ] 20 6.34 60 2.10 100 1.27 175 0.768 Doc. No. MD-5041 Rev. B Each LED channel needs a minimum of 400 mV headroom to sink constant regulated current up to 175 mA. If the input supply falls below 2 V, the undervoltage lockout circuit disables all LED channels. Any unused LED channels should be left open. The LED channels can withstand voltages up to 25 V. This makes the device ideal for driving long strings of high power LEDs from a high voltage source. 8 © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice CAT4104 APPLICATION INFORMATION SINGLE 12 V SUPPLY NIGHTLIGHT DETECTION The circuit shown in Figure 3 shows how to power the LEDs from a single 12 V supply using the CAT4104. Three external components are needed to create a lower voltage necessary for the VIN pin (below 5.5 V). The resistor R2 and zener diode Z provide a regulated voltage while the quiescent current runs through the N-Channel transistor M. The recommended parts are ON Semiconductor MM3Z6V2 zener diode (in SOD-323 package), and 2N7002L N-Channel transistor (in SOT23). The circuit shown in Figure 5 illustrates how to use the CAT4104 in an automatic night light application. The light sensor allows the CAT4104 to be disabled during the day and enabled during the night. Five external components are needed to properly configure the part for night detection. Resistor R3 limits the quiescent current through the N-Channel transistor M. Resistors R1 and R2 act as a voltage divider to create the required voltage to turn on transistor M, which disables the CAT4104. The recommended parts are ON Semiconductor 2N7002L N-Channel transistor (in SOT23) and the Microsemi LX1972 light sensor. For best performance, the LED light should not interfere with the light sensor. 12V C2 1µF R2 5kΩ M Z 6.2V VIN C1 0.1µF 5V LED1 CAT4104 LED2 EN/PWM LED3 RSET LED4 R3 100 kΩ VDD Light Sensor GND R1 R1 100 kΩ C2 1 µF C1 0.1 µF LED1 VIN CAT4104 LED2 VSS OFF ON Figure 3. Single Supply Driving 12 LEDs M R2 1 MΩ LED3 EN/PWM RSET R4 LED4 GND DAYLIGHT DETECTION The circuit in Figure 4 shows how to use CAT4104 in an automatic light sensor application. The light sensor allows the CAT4104 to be enabled during the day and disabled during the night. Two external components are required to configure the part for ambient light detection and conserve power. Resistor R1 sets the bias for the light sensor. The recommended part is Microsemi LX1972 light sensor. For best performance, the LED light should not interfere with the light sensor. Figure 5. Night Detection LED CURRENT DERATING The circuit shown in Figure 6 provides LED temperature derating to avoid over-driving the LED under high ambient temperatures, by reducing the LED current to protect the LED from over-heating. The positive thermo coefficient (PTC) thermistor RPTC is used for temperature sensing and should be located near the LED. As the temperature of RPTC increases, the gate voltage of the MOSFET M1 decreases. This causes the transistor M1 on-resistance to increase which results in a reduction of the LED current. The circuit is powered from a single VCC voltage of 5 V. The recommended parts are Vishay 70ºC thermistor PTCSS12T071DTE and ON Semiconductor 2N7002L N-Channel transistor (in SOT23). 5V C2 1 µF R1 100 kΩ VDD Light Sensor VIN C1 0.1 µF LED1 CAT4104 LED2 VSS OFF ON LED3 EN/PWM RSET R1 The PCB and heatsink for the LED should be designed such that the LED current is constant within the normal temperature range. But as soon as the ambient temperature exceeds a max threshold, the LED current drops to protect the LEDs from overheating. LED4 GND Figure 4. Daylight Detection © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice 9 Doc. No. MD-5041 Rev. B CAT4104 VCC power dissipation PD, and the ambient temperature, resulting in the following equation: 5V C2 1 µF RPTC VIN LED1 CAT4104 LED2 C1 0.1 µF EN/PWM LED3 RSET LED4 TJ = TAMB + PD (θJC + θCA) = TAMB + PD θJA When mounted on a double-sided printed circuit board with two square inches of copper allocated for “heat spreading”, the resulting θJA is about 90°C/W for the TDFN-8 package, and 160°C/W for the SOIC-8 package. 350 mA For example, at 60°C ambient temperature, the maximum power dissipation for the TDFN-8 is calculated as follow: GND R1 1436 Ω M1 PDmax = R2 5 kΩ Figure 6. LED Current Derating TJmax - TAMB 150 - 60 = =1W θJA 90 RECOMMENDED LAYOUT A small ceramic capacitor should be placed as close as possible to the driver VIN pin. The RSET resistor should have a Kelvin connection to the GND pin of the CAT4104. POWER DISSIPATION The power dissipation (PD) of the CAT4104 can be calculated as follows: PD = (VIN × IIN ) + Σ(VLEDN × ILEDN ) The board layout should provide good thermal dissipation through the PCB. In the case of the CAT4104VP2 in the TDFN package, a via can be used to connect the center tab to a large ground plane underneath as shown on figure 7. where VLEDN is the voltage at the LED pin, and ILEDN is the LED current. Combinations of high VLEDN voltage and high ambient temperature can cause the CAT4104 to enter thermal shutdown. In applications where VLEDN is high, a resistor can be inserted in series with the LED string to lower the power dissipation PD. Thermal dissipation of the junction heat consists primarily of two paths in series. The first path is the junction to the case (θJC) thermal resistance which is defined by the package style, and the second path is the case to ambient (θCA) thermal resistance, which is dependent on board layout. The overall junction to ambient (θJA) thermal resistance is equal to: Figure 7. CAT4104 Recommended Layout θJA = θJC + θCA For a given package style and board layout, the operating junction temperature TJ is a function of the Doc. No. MD-5041 Rev. B 10 © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice CAT4104 PACKAGE OUTLINE DRAWINGS SOIC 8-Lead 150 mil (V) (1)(2) 0F0F E1 E SYMBOL MIN A 1.35 1.75 A1 0.10 0.25 b 0.33 0.51 MAX c 0.19 0.25 D 4.80 5.00 E 5.80 6.20 E1 3.80 e PIN # 1 IDENTIFICATION NOM 4.00 1.27 BSC h 0.25 0.50 L 0.40 1.27 θ 0º 8º TOP VIEW D h A1 θ A c e b L SIDE VIEW END VIEW For current Tape and Reel information, download the PDF file from: http://www.catsemi.com/documents/tapeandreel.pdf. Notes: (1) All dimensions are in millimeters. Angles in degrees. (2) Complies with JEDEC standard MS-012. © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice 11 Doc. No. MD-5041 Rev. B CAT4104 TDFN 8-Pad 2 mm x 3 mm (VP2) (1)(2) 1F1F D A e b E2 E PIN#1 IDENTIFICATION A1 PIN#1 INDEX AREA D2 TOP VIEW SIDE VIEW SYMBOL MIN NOM MAX A 0.70 0.75 0.80 A1 0.00 0.02 0.05 A2 0.45 0.55 0.65 A3 b 0.25 A2 A3 FRONT VIEW 0.30 D 1.90 2.00 2.10 D2 1.30 1.40 1.50 E 2.90 3.00 3.10 E2 1.20 1.30 1.40 e L BOTTOM VIEW 0.20 REF 0.20 L 050 TYP 0.20 0.30 0.40 For current Tape and Reel information, download the PDF file from: http://www.catsemi.com/documents/tapeandreel.pdf. Notes: (1) All dimensions are in millimeters. (2) Complies with JEDEC standard MO-229. Doc. No. MD-5041 Rev. B 12 © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice CAT4104 EXAMPLE OF ORDERING INFORMATION (1) 2F2F Prefix CAT Device # Suffix 4104 Company ID Product Number V Package V: SOIC VP2: TDFN 4104 –G T3 Lead Finish G: NiPdAu Tape & Reel T: Tape & Reel 3: 3,000/Reel Notes: (1) All packages are RoHS-compliant (Lead-free, Halogen-free). (2) The standard plated finish is NiPdAu. (3) The device used in the above example is a CAT4104V-GT3 (SOIC, NiPdAu, Tape & Reel, 3,000/Reel). (4) For additional temperature options, please contact your nearest ON Semiconductor Sales office. © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice 13 Doc. No. MD-5041 Rev. B CAT4104 REVISION HISTORY Date Revision Description 26-Feb-09 A Initial Issue B Updated Electrical Operating Characteristics Added new Typical Performance Characteristics Updated Block Diagram Updated Application Information 13-Mar-09 ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303-675-2175 or 800-344-3860 Toll Free USA/Canada Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada Email: [email protected] Doc. No. MD-5041 Rev. B N. American Technical Support: 800-282-9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center: Phone: 81-3-5773-3850 14 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative © 2009 SCILLC. All rights reserved. Characteristics subject to change without notice