CAT3606 6-Channel Low Noise Charge Pump White LED Driver DESCRIPTION FEATURES The CAT3606 controls up to four LEDs for the main display and two LEDs for the sub-display in cellular phones. The device is capable of operating in either 1x (LDO) mode or 1.5x charge pump mode. All LED pin currents are regulated and tightly matched to achieve uniformity of brightness across the LCD backlight. An external resistor (RSET) sets the nominal output current. Drives up to 4 main LEDs and 2 sub LEDs Separate control for main and sub LEDs Compatible with supply voltage of 3V to 5.5V Power efficiency up to 90% Output current up to 30mA per LED High-frequency Operation at 1MHz 2 modes of operation 1x and 1.5x White LED detect circuitry on all channels Shutdown current less than 1µA Small ceramic capacitors Soft start and current limiting Short circuit protection 16-pad TQFN package, 0.8mm max height The device can deliver as much as 20mA per channel during low voltage operation (3V), and 30mA per channel during nominal operation (3.3V). A constant high-frequency switching scheme (1MHz) provides low noise and allows the use of very small value ceramic capacitors.. APPLICATION Cell phone main and sub-display backlight Navigation PDAs Digital Cameras A “zero” quiescent current mode can be achieved via the chip enable pin EN. The Main and Sub LEDs each have their own dedicated ON/OFF control pins ENM ¯¯¯, ENS ¯¯¯ Dimming can be achieved using either a DC voltage to control the RSET pin current, or by applying a PWM signal on the ENM ¯¯¯ and ENS ¯¯¯ pins. ORDERING INFORMATION Part Number Package Quantity per Reel Marking CAT3606HV4-T2 TQFN-16 (1) 2000 G366 CAT3606HV4-GT2 TQFN-16 (2) 2000 CDBB The device is available in a 16-pad TQFN package with a max height of 0.8mm. For Ordering Information details, see page 11. Notes: (1) Matte-Tin Plated Finish (RoHS-compliant). (2) NiPdAu Plated Finish (RoHS-compliant). TYPICAL APPLICATION CIRCUIT 1µF Li-Ion Battery C1+ C1- C2+ - CIN 1µF ON/OFF Sub Display COUT ENM ENABLE LED5-6 ENS 1µF LED1 EN LED2 LED3 LED4 20mA LED5 RSET © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Main Display CAT3606 ENABLE LED1-4 RSET 24kΩ C2VOUT VIN + 1µF GND LED6 1 Doc. No. MD-5009 Rev. C CAT3606 PIN CONFIGURATION (1) TQFN 16-lead 4 x 4mm (Top view) LED5 LED4 LED3 LED2 16 LED6 1 EN 2 15 14 13 12 LED1 11 C2+ GND PAD ENM 3 ENS 4 10 C29 C15 6 RSET VOUT 7 8 VIN C1+ PIN DESCRIPTIONS Pin Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 PAD Name LED6 EN ¯¯¯¯ ENM ¯¯¯¯ ENS RSET VOUT VIN C1+ C1 C2 C2+ LED1 LED2 LED3 LED4 LED5 GND Function LED6 cathode terminal Enable/shutdown input, active high Enable "main" input for LED1 to LED4, active low Enable "sub" input for LED5 and LED6, active low The LED output current is set by the current sourced out of the RSET pin Charge pump output connected to the LED anodes Supply voltage Bucket capacitor 1 terminal Bucket capacitor 1 terminal Bucket capacitor 2 terminal Bucket capacitor 2 terminal LED 1 cathode terminal LED 2 cathode terminal LED 3 cathode terminal LED 4 cathode terminal LED 5 cathode terminal Ground reference Notes: (1) The "exposed pad" under the package must be connected to the ground plane on the PCB. Doc. No. MD-5009 Rev. C 2 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3606 ABSOLUTE MAXIMUM RATINGS Parameter VIN, VOUT, LEDx voltage EN, ENM ¯¯¯ , ENS ¯¯¯ voltage RSET voltage RSET current Ambient Temperature Range Storage Temperature Range Lead Temperature ESD Ratings Human Body Model (HBM) Machine Model (MM) (1) Rating -0.3 to 7.0 -0.3 to VIN -0.3 to VIN ±1 -40 to +85 -65 to +160 300 Unit V V V mA ºC ºC ºC 2000 200 V V RECOMMENDED OPERATING CONDITIONS Parameter VIN Ambient Temperature Range Input/Output/Bucket Capacitors ILED per LED pin IOUT Total Output Current Range 3.0 to 5.5 -40 to +85 1 ± 20% Typical 0 to 30 0 to 150 Unit V ºC µF mA mA ELECTRICAL OPERATING CHARACTERISTICS Limits over recommended operating conditions unless specified otherwise. Typical values at TA = 25˚C, VIN = 3.5V, IRSET = 5µA. Symbol Parameter IQ Quiescent Current VRSET RSET Regulated Voltage ILED Programmed LED Current ILED ILED ILED-ACC ILED-DEV ROUT fOSC TDROPOUT Conditions VEN = 0V 1x Mode, No Load 1.5x Mode, No Load Min 1.17 IRSET = 5µA IRSET = 37µA IRSET = 78µA 3.3 ≤ VIN ≤ 4.5V LED Current Range with 6 LEDs 3.0 ≤ VIN ≤ 4.5V LED Current Range with 4 LEDs 3.3 ≤ VIN ≤ 4.5V 0.5mA ≤ ILED ≤ 3mA LED Current Accuracy 3mA ≤ ILED ≤ 30mA LED Channel Matching (ILED - ILEDAVG) / ILEDAVG Output Resistance (Open Loop) 1x Mode, 1.5x mode, IOUT = 100mA Charge Pump Frequency 1x to 1.5x Mode Transition Dropout Delay Typ 0.1 0.3 2.6 1.2 2.4 15.0 30.0 Max 1 1 5 1.23 Unit µA mA mA V mA 30 20 30 ±15 ±5 ±3 mA mA % 1.4 6.5 2.5 10 % Ω Ω 0.8 1.0 1.3 MHz 0.4 0.6 0.9 ms 1 µA IEN-CTR Input Leakage Current ¯¯¯ , ENS ¯¯¯ On Inputs EN, ENM VEN-CTR High Detect Threshold Low Detect Threshold ¯¯¯ , ENS ¯¯¯ On Inputs EN, ENM 0.8 0.7 1.3 0.4 ISC ILIM Input Current Limit Maximum Input Current VOUT = GND VOUT > 1V 30 200 45 400 60 600 V mA mA Notes: (1) Machine model is with 200pF capacitor discharged directly into each pin. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 3 Doc. No. MD-5009 Rev. C CAT3606 BLOCK DIAGRAM 1µF C1- VIN 3V to 4.2V C1+ C2- C2+ 1x mode (LDO) VIN Battery 1µF VOUT 1.5x Charge Pump CIN COUT 1µF 1µF Mode Control 1MHz Oscillator LED1 EN 20mA LED2 LED3 LED4 LED5 1.2V Ref RSET RSET 24kΩ ENM ENS LED6 Main Current Setting Sub 6 Current Sink Regulators LED Output Select GND Figure 2. CAT3606 Functional Block Diagram BASIC OPERATION At power-up, the CAT3606 starts operation in 1x mode. If it is able to drive the programmed LED current, it continues in 1x mode. If the battery voltage drops to a level where the LED current cannot be met, the driver automatically switches into 1.5x mode, to boost the output voltage high enough to achieve the nominal LED current. Doc. No. MD-5009 Rev. C The above sequence is reinitialized each and every time the chip is powered up or is taken out of shutdown mode (via EN pin). The use of the Main and Sub display enable pins (ENM ¯¯¯ or ENS ¯¯¯ ) does not affect the mode of operation. 4 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3606 LED CURRENT SETTING The unused LED channels can also be turned off by connecting the respective LED pins to VOUT. In which case, the corresponding LED driver is disabled and the typical LED sink current is only about 0.2mA. When the following equation is true on any channel, the driver turns off the LED channel: The LED current is set by the external resistor RSET connected between the RSET pin and ground. Table 1 lists various LED currents and the associated RSET resistor value for standard 1% precision surface mount resistors. VOUT - VLED ≤ 1V (LED channel OFF) Table 1. RSET Resistor Selection LED Current (mA) RSET (kΩ) 1 649 2 287 5 102 10 49.9 15 32.4 20 23.7 30 15.4 Note: The CAT3606 is designed to drive LEDs with forward voltage greater than 1V and is not compatible with resistive loads. ¯¯¯¯ and ¯¯¯¯ The enable lines ENM ENS allow to turn On or Off a group of LEDs as shown in Table 2. Table 2: LED Selection Control Lines LED Outputs Main LED1 - LED4 Sub LED5 -LED6 – – 1 – – 0 1 ON – 1 1 0 – ON 1 0 0 ON ON EN 0 ¯¯¯¯ ENM X ¯¯¯¯ ENS X 1 1 1 Notes: 1 = logic high (or VIN) 0 = logic low (or GND) – = LED output OFF X = don't care © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 5 Doc. No. MD-5009 Rev. C CAT3606 TYPICAL CHARACTERISTICS VIN = 3.6V, EN = VIN, ENM ¯¯¯ = ENS ¯¯¯ = GND, CIN = COUT = 1µF, RSET = 24kΩ (20mA per LED), TAMB = 25ºC, unless otherwise specified. Efficiency vs. Input Voltage (6 LEDs) Efficiency vs. Total LED Current (6 LEDs) 100 100 90 1x mode 80 EFFICIENCY [%] EFFICIENCY [%] 90 1.5x mode 70 60 20mA per LED 50 15mA per LED VIN = 4V 80 70 60 VIN = 3.2V (1.5x mode) 50 40 40 4.2 4.0 3.8 3.6 3.4 3.2 3.0 0 50 LED Current Change vs. Input Voltage 150 200 LED Current Change vs. Temperature 1.5 4 LED CURRENT CHANGE [%] LED CURRENT CHANGE [%] 100 TOTAL LED CURRENT [mA] INPUT VOLTAGE [V] 1.0 6 LEDs at 15mA 0.5 0.0 -0.5 -1.0 -1.5 3.0 3.2 3.4 3.6 3.8 4.0 3 6 LEDs at 15mA VIN = 4V 2 1 0 -1 -2 -3 -4 -50 4.2 -25 INPUT VOLTAGE [V] Ground Current vs. Input Voltage (1x mode) 50 75 100 125 GROUND CURRENT [mA] 0.5 0.3 0.2 6 LEDs OFF 0.1 3.2 3.4 3.6 3.8 4.0 0.4 0.3 0.2 6 LEDs OFF RSET = 500kΩ 0.1 0.0 4.2 -40 INPUT VOLTAGE [V] Doc. No. MD-5009 Rev. C 25 Ground Current vs. Temperature (1x mode) 0.4 0.0 3.0 0 TEMPERATURE [ºC] 0.5 GROUND CURRENT [mA] (1x mode ) -20 0 20 40 60 80 100 TEMPERATURE [ºC] 6 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3606 TYPICAL CHARACTERISTICS VIN = 3.6V, EN = VIN, ENM ¯¯¯ = ENS ¯¯¯ = GND, CIN = COUT = 1µF, RSET = 24kΩ (20mA per LED), TAMB = 25ºC, unless otherwise specified. Ground Current vs. Input Voltage (1.5x mode) Supply Current vs. Input Voltage GROUND CURRENT [mA] GROUND CURRENT [mA] 5.0 4.0 3.0 2.0 VIN = 3.6V all LEDs open 1.0 140 1.5x mode 120 100 1x mode 6 LEDs at 15mA 80 0.0 3.0 3.2 3.4 3.6 3.8 4.0 4.2 3.0 3.2 3.4 INPUT VOLTAGE [V] Oscillator Frequency vs. Input Voltage 4.0 4.2 1.10 CLOCK FREQUENCY [MHz] CLOCK FREQUENCY [MHz] 3.8 Oscillator Frequency vs. Temperature 1.10 1.05 1.00 6 LEDs at 20mA 0.95 0.90 1.05 1.00 0.95 VIN = 3.6V 6 LEDs at 15mA 0.90 3.0 3.2 3.4 3.6 3.8 4.0 -40 4.2 -20 0 20 40 60 80 100 TEMPERATURE [ºC] INPUT VOLTAGE [V] Output Resistance vs. Input Voltage (1x mode) Output Resistance vs. Input Voltage (1.5x mode) 10 OUTPUT RESISTANCE [Ω] 4 OUTPUT RESISTANCE [Ω] 3.6 INPUT VOLTAGE [V] 3 100mAload load 100mA 2 1 8 6 100mA load 100mA load 4 2 0 3.0 3.2 3.4 3.6 3.8 4.0 4.2 3.0 INPUT VOLTAGE [V] © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 7 3.2 3.4 3.6 3.8 INPUT VOLTAGE [V] 4.0 4.2 Doc. No. MD-5009 Rev. C CAT3606 TYPICAL CHARACTERISTICS VIN = 3.6V, EN = VIN, ENM ¯¯¯ = ENS ¯¯¯ = GND, CIN = COUT = 1µF, RSET = 24kΩ (20mA per LED), TAMB = 25ºC, unless otherwise specified. Switching Waveforms in 1.5x Mode Operating Waveforms in 1x Mode Power Up 6 LEDs at 15mA, VIN = 3V (1.5x Mode) Power Up 6 LEDs at 15mA, VIN = 3.6V (1x Mode) LED Current vs. R SET Line Transient Response in 1x Mode LED CURRENT [mA] 100.0 10.0 1.0 0.1 10 100 1000 10000 RSET [kΩ] Doc. No. MD-5009 Rev. C 8 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3606 TYPICAL CHARACTERISTICS VIN = 3.6V, EN = VIN, ENM ¯¯¯ = ENS ¯¯¯ = GND, CIN = COUT = 1µF, TAMB = 25ºC, unless otherwise specified. Foldback Current Limiting RSET Pin Voltage vs. Temperature 1.24 1x mode 4 RSET PIN VOLTAGE [V] OUTPUT VOLTAGE [V] 5 3 2 1 1.22 1.20 1.18 1.16 0 0 100 200 300 400 -50 500 -25 0 25 50 75 100 125 TEMPERATURE [ºC] OUTPUT CURRENT [mA] PWM Dimming at 1kHz on ENM and ENS RECOMMENDED LAYOUT When the driver is in the 1.5x charge pump mode, the 1MHz switching frequency operation requires to minimize trace length and impedance to ground on all 4 capacitors. A ground plane should cover the area on the bottom side of the PCB opposite to the IC and the bypass capacitors. Capacitors Cin and Cout require short connection to ground which can be done with multiple vias as shown on Figure 2. A square copper area matches the QFN16 exposed pad (GND) and must be connected to the ground plane underneath. The use of multiple via will improve the heat dissipation. Figure 2. PCB Layout © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 9 Doc. No. MD-5009 Rev. C CAT3606 PACKAGE OUTLINE DRAWING TQFN 16-Pad 4 x 4mm (HV4) (1)(2) A D DETAIL A E2 E PIN#1 ID PIN#1 INDEX AREA TOP VIEW SIDE VIEW SYMBOL MIN NOM MAX A 0.70 0.75 0.80 A1 0.00 0.02 0.05 A3 BOTTOM VIEW e b 0.20 REF b 0.25 0.30 0.35 D 3.90 4.00 4.10 D2 2.00 – 2.25 E 3.90 4.00 4.10 E2 2.00 – 2.25 e L D2 A1 L DETAIL A A 0.65 BSC 0.45 – 0.65 A3 A1 FRONT 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. (2) Complies with JEDEC standard MO-220. Doc. No. MD-5009 Rev. C 10 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3606 EXAMPLE OF ORDERING INFORMATION 1 Prefix CAT Device # 3606 Suffix HV4 – Product Number 3606 Optional Company ID G T2 Lead Finish G: NiPdAu Blank: Matte-Tin(4) Tape & Reel T: Tape & Reel 2: 2,000/Reel Package HV4: TQFN 4 x 4mm For Product Top Mark Codes, click here: http://www.catsemi.com/techsupport/producttopmark.asp Notes: (1) All packages are RoHS-compliant (Lead-free, Halogen-free). (2) The standard lead finish is NiPdAu. (3) The device used in the above example is a CAT3606HV4-GT2 (TQFN, NiPdAu Plated Finish, Tape & Reel, 2,000/Reel). (4) For Matte-Tin package option, please contact your nearest Catalyst Semiconductor Sales office. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 11 Doc. No. MD-5009 Rev. C REVISION HISTORY Date Rev. Reason 21-Jan-05 A Initial Issue 8-Jan-05 B 30-May-08 C Updated LED Current Setting Update Package Outline Drawing Delete PbSn plated finish; add NiPdAu plated finish Add Example of Ordering Information Add Top Mark Code Link Add MD- to document number Copyrights, Trademarks and Patents © Catalyst Semiconductor, Inc. Trademarks and registered trademarks of Catalyst Semiconductor include each of the following: Adaptive Analog™, Beyond Memory™, DPP™, EZDim™, LDD™, MiniPot™, Quad-Mode™ and Quantum Charge Programmable™ Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. CATALYST SEMICONDUCTOR MAKES NO WARRANTY, REPRESENTATION OR GUARANTEE, EXPRESS OR IMPLIED, REGARDING THE SUITABILITY OF ITS PRODUCTS FOR ANY PARTICULAR PURPOSE, NOR THAT THE USE OF ITS PRODUCTS WILL NOT INFRINGE ITS INTELLECTUAL PROPERTY RIGHTS OR THE RIGHTS OF THIRD PARTIES WITH RESPECT TO ANY PARTICULAR USE OR APPLICATION AND SPECIFICALLY DISCLAIMS ANY AND ALL LIABILITY ARISING OUT OF ANY SUCH USE OR APPLICATION, INCLUDING BUT NOT LIMITED TO, CONSEQUENTIAL OR INCIDENTAL DAMAGES. Catalyst Semiconductor 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 Catalyst Semiconductor product could create a situation where personal injury or death may occur. Catalyst Semiconductor reserves the right to make changes to or discontinue any product or service described herein without notice. Products with data sheets labeled "Advance Information" or "Preliminary" and other products described herein may not be in production or offered for sale. Catalyst Semiconductor advises customers to obtain the current version of the relevant product information before placing orders. Circuit diagrams illustrate typical semiconductor applications and may not be complete. Catalyst Semiconductor, Inc. Corporate Headquarters 2975 Stender Way Santa Clara, CA 95054 Phone: 408.542.1000 Fax: 408.542.1200 0Hwww.catsemi.com Document No: MD-5009 Revision: C Issue date: 05/30/08