CAT3604V 4-Channel Quad-Mode™ LED Driver with Open/Short LED Detection FEATURES DESCRIPTION The CAT3604V is a high efficiency Quad-ModeTM fractional charge pump that can drive up to four LEDs with input supply voltages as low as 2.5V. Quad-mode charge pump: 1x, 1.33x, 1.5x, 2x Drives up to 4 LEDs at 30mA each Pin compatible with industry standard ‘604 Open/short LED automatic detection Power efficiency up to 92% High resolution PWM dimming Low noise supply ripple in all modes Soft start and current limiting Short circuit and thermal overload protection 16-Pad TQFN package, 4mm x 4mm An external RSET resistor is used to control the LED channel brightness while channel diagnostics include automatic detection for both short and open LED channel conditions, ensuring the CAT3604V maintains the highest efficiency level in all operating modes. APPLICATION Each operating mode uses a constant high frequency switching scheme which allows the use of small form factor external ceramic capacitors while delivering excellent low noise input supply ripple up to 5.5 volts. The EN input control supports direct PWM dimming and can accommodate dimming frequencies in excess of 10kHz thereby providing extremely high resolution brightness levels. LCD Display Backlight Cellular Phones Digital Still Cameras Handheld Devices ORDERING INFORMATION Part Number The device is available in the 16-pad low profile 0.8mm thin QFN (4mm x 4mm). Package Qty per Reel Marking (1) CAT3604VHV4-GT2 TQFN-16 4 x 4mm TQFN-16 CAT3604VHV4-T2 4 x 4mm 2000 CDAK 2000 CDAF Note: (1) NiPdAu Plated Finish, RoHS compliant For other finishes, please contact factory For Ordering Information details, see page 14. PIN CONFIGURATION TYPICAL APPLICATION CIRCUIT 1µF 1µF LED1 LED2 LED3 LED4 16 EN NC 15 14 1 12 GND 2 11 C2+ CIN NC ON OFF 10 C2- 4 9 C16 RSET VOUT C2VOUT VOUT COUT 1µF CAT3604V LED1 3 5 C1- C2+ VIN 2.4V to 5.5V 1µF GND NC C1+ VIN 13 7 8 VIN C1+ © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 4.02kΩ 1 EN LED2 RSET LED3 GND 20mA LED4 Doc. No. MD-5029, Rev. B CAT3604V ABSOLUTE MAXIMUM RATINGS Parameter VIN, LEDx, C1±, C2± voltage VOUT voltage EN voltage Storage Temperature Range Junction Temperature Range Lead Temperature Rating 6 7 6 -65 to +160 -40 to +150 300 Unit V V V °C °C °C RECOMMENDED OPERATING CONDITIONS Parameter VIN Ambient Temperature Range ILED per LED pin Total Output Current LED Forward Voltage Range Rating 2.5 to 5.5 -40 to +85 0 to 25 0 to 100 1.3 to 4.3 Unit V °C mA mA V Typical application circuit with external components is shown on page 1. ELECTRICAL OPERATING CHARACTERISTICS (over recommended operating conditions unless specified otherwise) VIN = 3.6V, EN = High, TAMB = 25°C Symbol IQ IQSHDN ILED-ACC ILED-DEV Name Quiescent Current Shutdown Current LED Current Accuracy LED Channel Matching ILED Programmed LED Current VRSET RSET Regulated Voltage ROUT Output Resistance (open loop) FOSC Charge Pump Frequency ISC_MAX IIN_MAX Output short circuit Current Limit Input Current Limit LEDTH 1x to 1.33x, 1.33x to 1.5x or 1.5x to 2x Transition Thresholds at any LED pin VHYS 1x Mode Transition Hysteresis EN Pin • Internal Pull-down Resistor • Logic High Level • Logic Low Level Thermal Shutdown Thermal Hysteresis Undervoltage lockout (UVLO) threshold REN VHI VLO TSD THYS VUVLO Doc. No. MD-5029 Rev. B Conditions 1x mode, no load 1.33 x mode, no load 1.5x mode, no load 2x mode, no load VEN = 0V ILEDAVG / ILEDAVG-NOMINAL (ILED - ILEDAVG) / ILEDAVG RSET = 34.0kΩ RSET = 5.23kΩ RSET = 2.67kΩ Min Max 1 0.58 1x mode 1.33x mode, VIN = 3V 1.5x mode, VIN = 2.7V 2x mode, VIN = 2.4V 1.33x and 2x mode 1.5x mode VOUT < 0.5V VOUT > 1V Typ 1.0 1.7 2.2 2.4 0.8 1 ±2 ±1.5 2.4 15 30 0.6 0.8 5 5 10 1 1.3 50 250 mA 0.62 1.3 1.6 mV 400 mV 100 kΩ V V °C °C V 0.4 2 V Ω Ω Ω Ω MHz MHz mA mA 130 1.3 1.6 Units mA mA mA mA µA % % 150 20 1.8 2.0 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3604V A.C. CHARACTERISTICS For 2.5V ≤ VIN ≤ 5.5V, over full ambient temperature range -40 to +85°C. Symbol TLED TMD TPWRDWN Name LED current settling time from shutdown mode Mode transition time Conditions 1x mode, VIN = 4V 1.33x mode, VIN = 3.5V Device power down delay Min Typ 40 400 500 Max 0.9 1.5 Units μs µs ms TLED-ON LED on settling time 1 µs TLED-OFF LED off settling time 120 ns Figure 1. CAT3604V Timing Characteristics LED Current Setting The nominal LED current is set by the external resistor connected between the RSET pin and ground. Table 1 lists standard resistor values for several LED current settings. LED current (mA) 2 5 10 15 20 25 30 RSET (kΩ) 40.0 15.8 7.87 5.23 4.02 3.16 2.67 Table 1. Resistor RSET and LED current © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 3 Doc. No. MD-5029 Rev. B CAT3604V TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 80mA (4 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Efficiency vs. Input Voltage 100 VF = 3.3V 100 1.33x 1.5x 90 1x 80 2x 70 60 4.5 4.0 3.5 3.0 2.5 INPUT VOLTAGE [V] 60 4.2 4.0 3.8 3.6 3.4 3.2 INPUT VOLTAGE [V] 3.0 Quiescent Current vs. Temperature 4.0 4.0 QUIESCENT CURRENT [mA] VF = 3.3V 3.0 2.0 1.0 LEDs Off 0.0 2x 1.5x 3.0 2.0 1.33x 1.0 1x 0.0 -40 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 INPUT VOLTAGE [V] 0 40 80 TEMPERATURE [°C] 120 LED Current Change vs. Temperature LED CURRENT VARIATION [%] . LED Current Change vs. Input Voltage LED CURRENT VARIATION [%] . 1.33x 70 2.0 Quiescent Current vs. Input Voltage QUIESCENT CURRENT [mA] 80 40 40 VF = 3.3V 10 8 6 4 2 VF = 3.3V 0 -2 -4 -6 -8 -10 -40 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE [V] Doc. No. MD-5029 Rev. B 1x 50 50 10 8 6 4 2 0 -2 -4 -6 -8 -10 VF = 3.3V 90 EFFICIENCY [%] EFFICIENCY [%] Efficiency vs. Li-Ion Voltage 4 0 40 80 TEMPERATURE [°C] 120 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3604V TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 80mA (4 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Output Resistance vs. Input Voltage 12 1.3 1.2 OUTPUT RESISTANCE [Ω] . SWITCHING FREQUENCY [MHz] Switching Frequency vs. Temperature 1.5x Mode 1.1 1.0 0.9 1.33x, 2x Mode 0.8 0.7 -40 0 40 80 TEMPERATURE [°C] 8 6 1.33x 1.5x 4 1x 2 0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE [V] 120 Foldback Current Limit LED Current vs. LED Pin Voltage 4.0 40 1x Mode 3.5 3.0 LED CURRENT [mA] OUTPUT VOLTAGE [V] 2x 10 2.5 2.0 1.5 1.0 0.5 0.0 0 100 200 300 OUTPUT CURRENT [mA] 30 20 10 0 400 0 LED Current vs. RSET Resistance 50 100 150 200 250 LED PIN VOLTAGE [mV] 300 Line Transient Response (3.6V to 4.9V) LED CURRENT [mA] 100 10 1 1 10 RSET RESISTANCE [kΩ] © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 100 5 Doc. No. MD-5029, Rev. B CAT3604V TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 80mA (4 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. 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-5029, Rev. B 6 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3604V TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 80mA (4 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. Cold Power Up in 1x Mode Cold Power Up in 1.33x Mode Cold Power Up in 1.5x Mode Cold Power Up in 2x Mode Power Down (1x Mode) Cold Power Up (1x Mode) © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 7 Doc. No. MD-5029 Rev. B CAT3604V PIN DESCRIPTION Pin # Name Function 1 EN Device enable (active high). 2 NC Not connected inside the package. 3 NC Not connected inside the package. 4 NC Not connected inside the package. 5 RSET Connect resistor RSET to set the LED current. 6 VOUT Charge pump output connected to the LED anodes. 7 VIN Charge pump input, connect to battery or supply. 8 C1+ Bucket capacitor 1 Positive terminal 9 C1- Bucket capacitor 1 Negative terminal 10 C2- Bucket capacitor 2 Negative terminal 11 C2+ Bucket capacitor 2 Positive terminal 12 GND Ground Reference 13 LED4 LED4 cathode terminal. 14 LED3 LED3 cathode terminal. 15 LED2 LED2 cathode terminal. 16 LED1 LED1 cathode terminal. TAB GND 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 (1.8V), all the LED channels are disabled and the device enters shutdown mode. 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 LED4 provide the internal regulated current source for each of the LED cathodes. These pins enter high-impedance zero current state whenever the device is placed in shutdown mode. If an LED pin is directly tied to VOUT, that channel is disabled. EN is the enable input and the high resolution PWM dimming control. Levels of logic high and logic low are set at 1.3V and 0.4V respectively. When EN is initially taken high, the device becomes enabled and all LED currents are set according to the RSET resistor. To place the device into “zero current” shutdown mode, the EN pin must be held low for at least 1.5ms. 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. RSET is connected to the resistor (RSET) to set the current for the LEDs. The voltage at this pin regulated to 0.6V. The ground side of the external resistor should be star connected back to the GND of the PCB. In shutdown mode, RSET beomes high impedance. 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. Doc. No. MD-5029, Rev. B 8 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3604V BLOCK DIAGRAM C1- VIN VIN C1+ C2- C2+ VOUT 1x mode (LDO) 1.33x, 1.5x, 2x Charge Pump Mode Control 1, 1.3MHz Oscillator LED1 EN LED2 LED3 Reference Voltage RSET LED4 LED Channel Current Regulators Current Setting GND Figure 2. CAT3604V Functional Block Diagram BASIC OPERATION At power-up, the CAT3604V 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. mode and returning to 1x mode is called the 1x mode transition hysteresis (VHYS) and is about 500mV LED Current Selection The LED current is set to by the external resistor RSET as follows: 0 .6 V LED current = 132 × R SET If the input voltage is insufficient or falls to a level where the regulated currents cannot be maintained, the device automatically switches into 1.33x mode (after a fixed delay time of about 400μs). In 1.33x mode, the output voltage is approximately equal to 1.33 times the input supply voltage (less any internal voltage losses). The EN pin enables and disables the device. The LED driver enters a “zero current” shutdown mode if EN is held low for 1.5ms or more. As soon as the EN input goes low, all LED channels are instantly disabled, where the LED current is set to zero. As long as the CAT3604V is not in shutdown mode, the LEDs turn on as soon as the EN goes high. This sequence repeats in the 1.33x and 1.5x mode until the driver enters the 2x mode. In 1.5x mode, the output voltage is approximately equal to 1.5 times the input supply voltage. While in 2x mode, the output is approximately equal to 2 times the input supply voltage. If the device detects a sufficient input voltage is present to drive all LED currents in 1x mode, it will change automatically back to 1x mode. This only applies for changing back to the 1x mode. The difference between the input voltage when exiting 1x © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 9 Doc. No. MD-5029 Rev. B CAT3604V External Components The driver requires four 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. Unused LED Channels For applications not requiring all the channels, it is recommended to connect the unused LED pins directly to VOUT (see Figure 3). 1µF C1+ VIN CIN C1- C2+ VIN 1µF C2VOUT CAT3604V LED1 ON OFF In 1x mode, the device operates in linear mode and does not introduce switching noise back onto the supply. COUT 1µF EN LED2 RSET LED3 GND RSET 1µF 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. LED4 Figure 3. Application with 3 LEDs Protection Mode If an LED is disconnected, the device senses that, run the diagnostics, then ignores that channel and goes back to the most effective mode. When all LEDs are disconnected, the device runs diagnostics and goes to 1x mode where the output is basically equal to the input voltage. As soon as the output exceeds about 6V, the driver resets itself and reevaluate the mode. If the die temperature reaches +150°C, the device enters a thermal protection shutdown mode. When the device temperature drops to about +130°C, the device resumes normal operation. LED Selection LEDs with forward voltages (VF) ranging from 1.3V to 4.3V may be used. Selecting LEDs with lower VF is recommended in order to extend battery life and keep the driver in 1x mode longer as the battery voltage decreases. For example, if a 3.3V VF LED is selected instead of a 3.5V VF LED, the driver will stay in 1x mode for a lower supply voltage of 0.2V. Doc. No. MD-5029, Rev. B Figure 4. PCB Layout 10 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3604V PWM DIMMING The EN pin is used to provide total Shutdown of the device as well as High Resolution PWM dimming control on the LED Channels. OUTPUT CURRENT [%] 100 Shutdown of the device occurs after the EN pin has been held low for 1.5ms. During the “soft-start” powerup sequence from the shutdown mode, the LED current typically settles within 40µs (for 1X mode operation). This LED current settling time becomes 400µs if 1.33X operation is needed (i.e low battery voltage). For High Resolution PWM dimming control (typically frequencies at 2kHz or above), the device will remain powered and only the LED channels output will be switched on and off during the PWM (the rest of the device will remain powered-up). This allows the output channels to have “instant-on” response, where the LED current settles within 1µs of the applied PWM dimming signals. This “instant-on” modes makes the device suitable for extremely high frequency PWM dimming schemes. 70% DC 80 70 60 50 40 30 30% DC 20 10 0.1 1 10 100 PWM FREQUENCY [kHz] Figure 5. Output current vs. PWM frequency For best performance, the duty cycle off-time TOFF should meet the following timing limits: Figure 5 shows the output current for PWM frequencies up to 100kHz and with duty cycles of 30% and 70%. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 90 11 for slow frequency ≤ 600Hz, TOFF ≥ 800µs for fast frequency ≥ 1kHz, TOFF ≤ 400µs Doc. No. MD-5029 Rev. B CAT3604V TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6V, IOUT = 80mA (4 LEDs at 20mA), CIN = COUT = C1 = C2 = 1μF, TAMB = 25°C unless otherwise specified. 10kHz PWM waveform (1x mode) 10kHz PWM waveform (1.33x mode) 300Hz PWM waveform (1x mode) Dimming Linearity, PWM at 200Hz 100 DIMMING [%] 80 1x mode VIN = 4V 60 40 1.33x mode VIN = 3.5V 20 0 0 Dimming Linearity, PWM at 500Hz 100 Dimming Linearity, PWM at 30kHz 100 100 80 80 1x mode VIN = 4V 60 40 DIMMING [%] DIMMING [%] 20 40 60 80 DUTY CYCLE [%] 1.33x mode VIN = 3.5V 20 1x mode VIN = 4V 60 40 1.33x mode VIN = 3.5V 20 0 0 Doc. No. MD-5029, Rev. B 20 40 60 80 DUTY CYCLE [%] 0 100 0 12 20 40 60 80 DUTY CYCLE [%] 100 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice CAT3604V 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 – 2.90 E 3.90 4.00 4.10 E2 2.00 – 2.90 e L D2 A1 L DETAIL A A 0.65 BSC 0.30 – 0.60 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 satndard MO-220. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 13 Doc. No. MD-5029 Rev. B CAT3604V EXAMPLE OF ORDERING INFORMATION (1) Prefix Device # CAT 3604V Suffix HV4 Product Number Optional Company ID Package HV4: TQFN – G T2 Lead Finish Blank: Matte-Tin G: NiPdAu Tape & Reel T: Tape & Reel 2: 2,000/Reel 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 CAT3604VHV4-GT2 (TQFN, Tape & Reel, 2,000/Reel). (4) For additional package and temperature options, please contact your nearest Catalyst Semiconductor Sales office. Doc. No. MD-5029, Rev. B 14 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice REVISION HISTORY Date Rev. Reason 04-Dec-07 A Initial Release 28-Apr-08 B Update Package Outline Drawing – TQFN 16-Pad 4 x 4 (HV4) 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 www.catsemi.com Document No: MD-5029 Revision: B Issue Date: 04/28/08