CAT3637HV3-GT2

CAT3637 6-Channel Programmable High Efficiency ® Quad-Mode LED Driver FEATURES High efficiency 1.33x charge pump Quad-Mode charge pump: 1x, 1.33x, 1.5x, 2x Drives 6 LEDs between 30mA and 0mA each 1-wire EZDimTM interface with 2mA step Power efficiency up to 92% Low noise input ripple in all modes “Zero” current shutdown mode Soft start and current limiting Short circuit protection Thermal shutdown protection Tiny 3mm x 3mm, 16-pad TQFN package DESCRIPTION The CAT3637 is a high efficiency Quad-Mode fractional charge pump that can drive up to six LEDs programmable by a 1-wire digital interface. The inclusion of a 1.33x fractional charge pump mode increases device efficiency by up to 10% over traditional 1.5x charge pumps with no added external capacitors. Low noise input ripple is achieved by operating at a constant switching frequency which allows the use of small external ceramic capacitors. The multi-fractional charge pump supports a wide range of input voltages from 2.5V to 5.5V. The EN/SET logic input functions as a chip enable and a digital programming interface for setting the current in the LED channels. The 1-wire pulse-programming interface supports 15 linear steps from zero current to 30mA fullbrightness in 2mA steps. The device is available in a tiny 16-pad TQFN 3 x 3mm package with a maximum height of 0.8mm. Catalyst Semiconductor’s Quad-Mode 1.33x, charge pump switching architecture is patented. Package Marking JAAM APPLICATIONS LCD Display Backlight Cellular Phones Digital Still Cameras Handheld Devices ORDERING INFORMATION Part Number CAT3637HV3-GT2 Quantity per Reel 2000 (1) For Ordering Information details, see page 13. Note: (1) NiPdAu Plated Finish (RoHS-compliant) 16-lead TQFN 3mm x 3mm Package PIN CONFIGURATION (top view) EN/SET 16 LED6 LED5 LED4 LED3 1 2 3 4 5 6 7 8 TYPICAL APPLICATION CIRCUIT 1µF 1µF 15 GND LED1 14 NC 13 12 C211 C2+ 10 C19 C1+ NC VIN 2.5V to 5.5V CIN 1µF C1VIN C1+ C2C2+ VOUT VOUT CAT3637 1-Wire Programming EN/SET GND LED1 LED2 LED3 LED4 LED5 LED6 COUT 1µF © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice LED2 VOUT VIN 1 Doc. No. MD-5033 Rev. C CAT3637 ABSOLUTE MAXIMUM RATINGS Parameter VIN, LEDx, C1±, C2± voltage VOUT Voltage EN/SET Voltage Storage Temperature Range Junction Temperature Range(1) Lead Temperature Rating 6 7 VIN + 0.7V -65 to +160 -40 to +150 300 Unit V V V °C °C °C RECOMMENDED OPERATING CONDITIONS Parameter VIN Ambient Temperature Range(1) ILED per LED pin Total Output Current Range 2.5 to 5.5 -40 to +85 0 to 30 0 to 180 Unit V °C mA mA ELECTRICAL OPERATING CHARACTERISTICS Symbol IQ IQSHDN ILED-ACC ILED-DEV Name Quiescent Current Shutdown Current LED Current Accuracy LED Channel Matching (over recommended operating conditions unless specified otherwise) VIN = 3.6V, EN = High, TAMB = 25°C Conditions 1x mode, VIN = 4.2V 1.33 x mode, VIN = 3.3V 1.5x mode, VIN = 2.8V 2x mode, VIN = 2.5V VEN = 0V 2mA ≤ ILED ≤ 30mA ILED − ILEDAVG ILED 1x mode, IOUT = 120mA 1.33x mode, IOUT = 120mA 1.5x mode, IOUT = 120mA 2x mode, IOUT = 120mA 1.33x and 2x mode 1.5x mode VOUT < 0.5V Min Typ 1.5 2.8 3.7 3.8 ±3 ±1 0.5 3.5 3.5 6 0.8 1.1 80 150 VIN - Highest LED VF VOUT > 1V 1.3 0.4 150 20 2 400 120 450 100 Max Units mA mA mA mA µA % % Ω Ω Ω Ω MHz MHz mA mV mV µs mA kΩ V V °C °C V 1 ROUT Output Resistance (open loop) FOSC ISC_MAX LEDTH VHYS TDF IIN_MAX REN/DIM VHI VLO TSD THYS VUVLO Charge Pump Frequency Output short circuit Current Limit 1x to 1.33x or 1.33x to 1.5x or 1.5x to 2x Transition Thresholds at any LEDx pin 1.33x to 1x Transition Hysteresis Mode Transition Filter Delay Input Current Limit EN/DIM Pin • Internal Pull-down Resistor • Logic High Level • Logic Low Level Thermal Shutdown Thermal Hysteresis Undervoltage lockout (UVLO) threshold 0.6 0.8 1.1 1.4 Typical application circuit with external components is shown on page 1. Notes: (1) Package thermal resistance is below 50°C/W when mounted on FR4 board. Doc. No. MD-5033 Rev. C 2 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice CAT3637 RECOMMENDED EN/SET TIMING Symbol TLO THI TOFF TD Name EN/SET program low time EN/SET program high time EN/SET low time to shutdown LED current settling time For 2.5 ≤ VIN ≤ 5.5V, over full ambient temperature range -40º to +85ºC. Conditions Min 0.2 0.2 1.5 10 Typ Max 100 Units μs μs ms μs THI EN/SET TLO TD LED Current 28mA 30mA 6mA TOFF Shutdown 0mA 2mA 4mA 0mA 2mA Shutdown Figure 1. EN/SET One Wire Addressable Timing Diagram © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice 3 Doc. No. MD-5033 Rev. C CAT3637 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 120mA (6 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Efficiency vs. Input Voltage 100 90 EFFICIENCY [%] 80 70 60 50 40 4.5 4.0 3.5 3.0 2.5 INPUT VOLTAGE [V] 2.0 VF = 3.3V 1.33x 1x EFFICIENCY [%] Efficiency vs. Li-Ion Voltage 100 VF = 3.3V VF = 3.0V 1.5x 2x 90 80 70 60 50 40 Traditional 1.5x Charge Pump 4.2 4.0 3.8 3.6 3.4 3.2 INPUT VOLTAGE [V] 3.0 LED Current Change vs. Input Voltage LED CURRENT VARIATION [%] . 10 8 6 4 2 0 -2 -4 -6 -8 -10 5.5 5.0 4.5 4.0 3.5 3.0 INPUT VOLTAGE [V] 2.5 VF = 3.3V LED Current Change vs. Temperature LED CURRENT VARIATION [%] . 10 8 6 4 2 0 -2 -4 -6 -8 -10 -40 -20 0 20 40 60 TEMPERATURE [°C] 80 Quiescent Current vs. Input Voltage 6.0 QUIESCENT CURRENT [mA] 5.0 4.0 3.0 2.0 1.0 0.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 INPUT VOLTAGE [V] VF = 3.3V Doc. No. MD-5033 Rev. C 4 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice CAT3637 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 120mA (6 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Switching Frequency vs. Temperature SWITCHING FREQUENCY [MHz] 1.2 1.1 1.0 0.9 0.8 0.7 0.6 -40 -20 0 20 40 60 TEMPERATURE [°C] 80 1.33x, 2x Mode 1.5x Mode OUTPUT RESISTANCE [ Ω] . Output Resistance vs. Input Voltage 10 VF = 3.3V 8 6 4 2 0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 INPUT VOLTAGE [V] 1.5x 2x 1.33x 1x Power Up in 1x Mode Power Up in 1.33x Mode Power Up in 1.5x Mode Power Up in 2x Mode © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice 5 Doc. No. MD-5033 Rev. C CAT3637 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 120mA (6 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Power Up Delay (1x Mode) Power Down Delay (1x Mode) Operating Waveforms in 1x Mode Switching Waveforms in 1.33x Mode Switching Waveforms in 1.5x Mode Switching Waveforms in 2x Mode Doc. No. MD-5033 Rev. C 6 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice CAT3637 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 120mA (6 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Foldback Current Limit 4.0 OUTPUT VOLTAGE [V] 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0 100 200 300 400 OUTPUT CURRENT [mA] 500 1x Mode LED Brightness Levels LED Settling Time © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice 7 Doc. No. MD-5033 Rev. C CAT3637 PIN DESCRIPTION Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13/14 15 16 TAB Name LED6 LED5 LED4 LED3 LED2 LED1 VOUT VIN C1+ C1C2+ C2NC GND EN/SET TAB Function LED6 cathode terminal LED5 cathode terminal LED4 cathode terminal LED3 cathode terminal LED2 cathode terminal LED1 cathode terminal Charge pump output, connect to LED anodes Charge pump input, connect to battery or supply Bucket capacitor 1, positive terminal Bucket capacitor 1, negative terminal Bucket capacitor 2, positive terminal Bucket capacitor 2, negative terminal No connect Ground reference Device enable (active high) and 1 wire control input Connect to GND on the PCB PIN FUNCTION VIN is the supply pin for the charge pump. A small 1μF ceramic bypass capacitor is required between the VIN pin and ground near the device. The operating input voltage range is from 2.5V to 5.5V. Whenever the input supply falls below the under-voltage threshold (2V) all the LED channels will be automatically disabled and the device register are reset to default values. EN/SET is the enable and one wire addressable control logic input for all LED channels. Guaranteed levels of logic high and logic low are set at 1.3V and 0.4V respectively. When EN/SET is initially taken high, the device becomes enabled and all LED currents remain at 0mA. To place the device into zero current mode, the EN/SET pin must be held low for more than 1.5ms. VOUT is the charge pump output that is connected to the LED anodes. A small 1μF ceramic bypass capacitor is required between the VOUT pin and ground near the device. GND is the ground reference for the charge pump. The pin must be connected to the ground plane on the PCB. C1+, C1- are connected to each side of the ceramic bucket capacitor C1. C2+, C2- are connected to each side of the ceramic bucket capacitor C2. LED1 to LED6 provide the internal regulated current for each of the LED cathodes. These pins enter high-impedance zero current state whenever the device is placed in shutdown mode. TAB 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. Doc. No. MD-5033 Rev. C 8 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice CAT3637 SIMPLIFIED BLOCK DIAGRAM C1C1+ C2C2+ VIN 1x mode (LDO) 1.33x, 1.5x, 2x Charge Pump VOUT Mode Control EN/SET 100kΩ Serial Interface Reference Voltage 0.8, 1.1MHz Oscillator LED1 LED2 LED3 LED4 LED5 LED6 Registers Current Setting DAC 6 Current Regulators GND Figure 2. CAT3637 Functional Block Diagram BASIC OPERATION At power-up, the CAT3637 starts operating in 1x mode where the output will be approximately equal to the input supply voltage (less any internal voltage losses). If the output voltage is sufficient to regulate all LED currents, the device remains in 1x operating mode. If the output voltage is insufficient or falls to a level where the regulated current cannot be maintained, the device automatically switches into 1.33x mode (after a fixed delay time of about 120μs). In 1.33x mode, the output voltage is approximately equal to 1.33 times the input supply voltage (less any internal voltage losses). If the output voltage is still insufficient or falls to a level where the regulated currents cannot be maintained, the device will automatically switch to the 1.5x mode (after a fixed delay time of about 400μs). In 1.5x mode, the output is approximately equal to 1.5 times the input supply voltage (less any internal voltage losses). If the output voltage is still insufficient to drive the LEDs, it will automatically switch into 2x mode where the output is approximately equal to 2 times the input supply voltage (less any internal voltage losses). If the device detects a sufficient output voltage to drive all LED currents in 1x mode, it will revert back to 1x mode. This only applies for changing back to the 1x mode. © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice 9 Doc. No. MD-5033 Rev. C CAT3637 LED Current Setting The current in each of the six LED channels is programmed through the 1-wire EN/SET digital control input. At the initial power-up and once the EN/SET is set high, the LED current remains at zero in all channels. On the first EN/SET pulse (positive edge), the current is set to 2mA in all channels. On each consecutive pulse, the current is incremented by 2mA. On the 15th pulse, the current is equal to the full scale of 30mA. On the following pulse (16th pulse), the current goes back to zero and the previous sequence can be repeated. The EN/SET pin can be pulsed at high frequency 15 times to decrement the current by 2mA or to program the current from 0mA to 30mA. The maximum EN/SET signal frequency for programming the LED current is 2.5MHz. To power-down the device and turn-off all current sources, the EN/SET input should be kept low for a duration TOFF of 1.5ms or more. The driver typically powers-down with a delay of about 1ms. Figure 3. EN/SET One Wire Addressable Timing Diagram THI EN/SET TLO TD LED Current 28mA 30mA 6mA TOFF Shutdown 0mA 2mA 4mA 0mA 2mA Shutdown Figure 4. EN/SET Program Increasing / Decreasing LED Current by 2mA Doc. No. MD-5033 Rev. C 10 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice CAT3637 Unused LED Channels For applications with 5 LEDs or less, unused LEDs can be disabled by connecting the LED pin directly to VOUT, as shown on Figure 4. If LED pin voltage is within 1V of VOUT, then the channel is switched off and a 200μA test current is placed in the channel to sense when the channel moves below VOUT – 1V. 1µF 1µF External Components The driver requires two external 1μF ceramic capacitors for decoupling input, output, and for the charge pump. Both capacitors type X5R and X7R are recommended for the LED driver application. In all charge pump modes, the input current ripple is kept very low by design and an input bypass capacitor of 1μF is sufficient. In 1x mode, the device operates in linear mode and does not introduce switching noise back onto the supply. COUT 1µF VIN 2.5V to 5.5V CIN 1µF C1VIN C1+ C2- C2+ VOUT VOUT CAT3637 1-Wire Programming EN/SET GND LED1 LED2 LED3 LED4 LED5 LED6 Recommended Layout In charge pump mode, the driver switches internally at a high frequency. It is recommended to minimize trace length to all four capacitors. A ground plane should cover the area under the driver IC as well as the bypass capacitors. Short connection to ground on capacitors CIN and COUT can be implemented with the use of multiple via. A copper area matching the TQFN exposed pad (TAB) must be connected to the ground plane underneath. The use of multiple via improves the package heat dissipation. Figure 5. Five LED Application Protection Mode If an LED is disconnected, the output voltage VOUT automatically limits at about 5.5V. This is to prevent the output pin from exceeding its absolute maximum rating. If the die temperature exceeds +150°C the driver will enter a thermal protection shutdown mode. When the device temperature drops by about 20°C the device will resume normal operation. LED Selection LEDs with forward voltages (VF) ranging from 1.3V to 5.0V may be used with the CAT3637. Selecting LEDs with lower VF is recommended in order to improve the efficiency by keeping the driver in 1x mode longer as the battery voltage decreases. For example, if a white LED with a VF of 3.3V is selected over one with VF of 3.5V, the CAT3637 will stay in 1x mode for lower supply voltage of 0.2V. This helps improve the efficiency and extends battery life. Figure 6. Recommended Layout © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice 11 Doc. No. MD-5033 Rev. C CAT3637 PACKAGE OUTLINE DRAWING TQFN 16-Pad 3 x 3mm (HV3)(1)(2) D A e b L E E2 PIN#1 ID PIN#1 INDEX AREA TOP VIEW A1 SIDE VIEW D2 BOTTOM VIEW SYMBOL MIN NOM MAX A A1 A3 b D D2 E E2 e L 0.70 0.00 0.18 2.90 1.40 2.90 1.40 0.30 0.75 0.02 0.20 REF 0.25 3.00 – 3.00 – 0.50 BSC 0.40 0.80 0.05 A A1 A3 FRONT VIEW 0.30 3.10 1.80 3.10 1.80 0.50 For current Tape & 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-5033 Rev. C 12 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice CAT3637 EXAMPLE OF ORDERING INFORMATION(1) Prefix CAT Device # 3637 Suffix HV3 – G T2 Product Number 3637 Optional Company ID Package HV3: TQFN 3 x 3mm Lead Finish G: NiPdAu Tape & Reel T: Tape & Reel 2: 2000/Reel 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 CAT3637HV3–GT2 (TQFN, NiPdAu, Tape & Reel, 2000 pcs / Reel). (4) For additional package and temperature options, please contact your nearest ON Semiconductor Sales office. © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice 13 Doc. No. MD-5033 Rev. C CAT3637 REVISION HISTORY Date 07-Mar-08 07-Aug-08 12-Nov-08 Rev. A B C Description Initial Issue Changed “Quad-Mode™” to “Quad-Mode®” Change logo and fine print to ON Semiconductor 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: orderlit@onsemi.com 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 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative Doc. No. MD-5033 Rev. C 14 © 2008 SCILLC. All rights reserved. Characteristics subject to change without notice