CAT4134_08 CATALYST | Alldatasheet
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Catalyst Semiconductor, Inc. 1 Doc. No. MD-5021 Rev. B Characteristics subject to change without notice. 500mA Dual Channel Movie/Flash LED Driver
FEATURES
Dual Mode (Movie or Flash) operation Independent Movie/Flash LED current control Can drive 2, 3, 4 or 6 LEDs High LED Current (250mA max per channel) Power efficiency up to 85% Dual frequency mode 1.2MHz and 900kHz Soft-start inrush current Adjustable overvoltage protection Thermal shutdown protection Operating temperature range -40ºC to +85ºC 12-pad TDFN 3mm x 3mm package
APPLICATIONS
Camera flash Flash light High-power white LEDs Digital still cameras Color LCD backlighting
ORDERING INFORMATION
CAT4134HV2-T2 TDFN-12 (1) 2,000 HAAS CAT4134HV2-GT2 TDFN-12 (2) 2,000 HAAU Notes: (1) Matte-Tin Plated Finish (RoHS-compliant). (2) NiPdAu Plated Finish (RoHS-compliant). PIN CONFIGURATION 12-Pad TDFN 3mm x 3mm Top View
DESCRIPTION
The CAT4134 is a high power, dual channel boost converter which provides two matched LED currents. Output current levels are controlled by one of two resistors RSET or RFLASH. When the FLASH input pin is low (movie mode), RSET sets the current. When FLASH is high (flash mode), the resistor RFLASH sets the LED current. Each channel drives two or three white LEDs in series and provides a regulated current to control their brightness. Input supply down to 3V is supported, making the device ideal for Li-Ion battery applications. High frequency low noise operation allows the device to be used with small external inductors and ceramic capacitors while still maintain ing excellent efficiency. When not in use the device can be placed into a “zero” quiescent mode via the shutdown pin. In addition to soft-start control and current limiting, the CAT4134 include thermal shutdown protection. A dedicated overvoltage pin (OVP) allows the user to limit the maximum LED supply voltage. The device is packaged in the 12-pad TDFN 3mm x 3mm. For Ordering Information details, see page 12. TYPICAL APPLICATION CIRCUIT FLASH EN PGND AGND LED2 LED1 OVP SW SW VIN RSET RFLASH TAB is GND3 VOUT RSET 20kΩ RFLASH 18kΩ 10µF L D LED2 OVP LED1 AGND PGND CAT4134 VIN EN FLASH RFLASH RSET SW OFF ON 22µH3V to 4.2V 10µF VIN 100kΩ 1MΩ L = Sumida CDRH3D16-220 D = Central CMDSH05-4 (500mA) C2 = 10µF (rated 16V)
Doc. No. MD-5021 Rev. B 2 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice. ABSOLUTE MAXIMUM RATINGS Parameters Ratings Units SW voltage 20 V VIN voltage 8 V EN, FLASH, RSET, RFLASH voltage VIN + 0.6V V LED1, LED2 voltage 8 V Output Current per Channel 300 mA Storage Temperature Range -65 to +160 °C Junction Temperature Range -40 to +125 °C Lead Temperature 300 °C ESD Rating – Human Body Model (HBM) 2000 V RECOMMENDED OPERATING CONDITIONS Parameter Range Units VIN 2.8 to 4.2 V Ambient Temperature Range -40 to +85 °C Flash mode current per channel 25 to 250 mA Movie mode current per channel 5 to 50 mA ELECTRICAL OPERATING CHARACTERISTICS Over recommended operating conditions unless specified otherwise. VIN = 3.6V, EN = VIN and at ambient temperature of 25ºC. Symbol Parameter Conditions Min Typ Max Unit IQ Quiescent Current (not switching) VLED1 > 0.5V, VLED2 > 0.5V 100 250 µA ISD Shutdown Current EN = 0V 1 µA ISW Switch Current Limit Movie Mode (FLASH = Low) Flash Mode (FLASH = High) 0.5 1.7 2 A RSW Switch Resistance I SW = 1000mA 0.3 0.5 Ω ILK Switch Leakage Cu rrent Switch Off, V SW = 5V 5 µA FOSC Oscillator Frequency Movie Mode Flash Mode 1.2
0.9 MHz
VOVP OVP pin threshold 1.10 1.20 1.30 V η Efficiency V OUT = 10V, Load = 200mA 85 % TSD Thermal Shutdown 150 ºC THYST Thermal Hysteresis 20 ºC VUVLO Undervoltage Lock Out (UVLO) Threshold Disabled when VIN < VUVLO 1.9 2.2 V EN LOGIC CONTROL INPUT VSDHI VSDLO Logic High Threshold Logic Low Threshold EN > V SDHI Enables Device 0.4 0.7 0.7 1.5 V ISDBIAS Input Bias current EN = 3V 10 40 µA
© Catalyst Semiconductor, Inc. 3 Doc. No. MD-5021 Rev. B Characteristics subject to change without notice. ELECTRICAL OPERATING CHARACTERISTICS (continued) Over recommended operating conditions unless specified otherwise. VIN = 3.6V, EN = VIN and at ambient temperature of 25ºC. Symbol Parameter Conditions Min Typ Max Unit VRSET RSET pin voltage 22kΩ < RSET < 200kΩ 1.10 1.20 1.30 V VRFLASH RFLASH pin voltage 22kΩ < RFLASH < 200kΩ 1.10 1.20 1.30 V VLED LED1, LED2 Pin Voltage (whichever is the lower) Both Flash and Movie Mode (lower voltage pin is regulated) 400 mV ILED Programmed LED Current RSET = 21.6kΩ RFLASH = 43.2kΩ RFLASH = 21.6kΩ 100 mA ILED-RAN LED Current Adjust Range per LED output In Movie mode In Flash mode 25 50 200 mA ILED-ACC LED Current Accuracy ±5 % ILED-DEV LED Current Matching ±5 % FLASH CONTROL LOGIC INPUT VFHI VFLO Logic High Threshold Logic Low Threshold FLASH > V FHI Flash Enabled 0.4 0.7 0.7 1.5 V IINPUT Input Bias current FLASH = 3V 10 40 µA
Doc. No. MD-5021 Rev. B 4 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice. TYPICAL CHARACTERISTICS VIN = 3.6V, FLASH = VIN, C IN = 4.7µF, C OUT = 10µF, L = 22µH with 2 LEDs at 100mA, T AMB = 25ºC, unless otherwise specified. LED Current Regulation (100mA load) -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 INPUT VOLTAGE [V] LED CURRENT CHANGE [%]
1 LED
2 LEDs
LED Current Regulation (200mA load, Flash) -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 INPUT VOLTAGE [V] LED CURRENT CHANGE [%] Current Gain vs. RFLASH 1600 1650 1700 1750 1800 1850 1900 0 50 100 150 200 Rflash [kohm] CURRENT GAIN (Iout / Iflash) . VIN= 3.6V LED Current Regulation (100mA load, Flash) -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 INPUT VOLTAGE [V] LED CURRENT CHANGE [%]
2 LEDs at 100mA
Efficiency vs. Output Current (Flash mode) 0 50 100 150 200 250 TOTAL LED CURRENT [mA] EFFICIENCY (%) . VIN = 3.6V Efficiency vs. Input Voltage (Flash mode) INPUT VOLTAGE [V] EFFICIENCY (%) .
© Catalyst Semiconductor, Inc. 5 Doc. No. MD-5021 Rev. B Characteristics subject to change without notice. TYPICAL CHARACTERISTICS VIN = 3.6V, FLASH = VIN, C IN = 4.7µF, C OUT = 10µF, L = 22µH with 2 LEDs at 100mA, T AMB = 25ºC, unless otherwise specified. Power-up Transient (2 LEDs at 200mA) Power-up Transient (2 LEDs at 200mA) Power-up Transient (2 LEDs at 200mA) Power-up Transient (2 LEDs at 200mA) Switching Waveform in Flash mode (2 LEDs)
Doc. No. MD-5021 Rev. B 6 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice. TYPICAL CHARACTERISTICS VIN = 3.6V, CIN = 4.7µF, COUT = 10µF, L = 22µH with 2 LEDs at 100mA, TAMB = 25ºC, unless otherwise specified. Switching Frequency vs. Supply Voltage 800 900 1000 1100 1200 1300 INPUT VOLTAGE [V] CLOCK FREQUENCY [kHz] Movie mode 20mA per LED Flash mode 50mA per LED Enable Flash waveform
© Catalyst Semiconductor, Inc. 7 Doc. No. MD-5021 Rev. B Characteristics subject to change without notice. PIN DESCRIPTION Pin # Name Function 1 FLASH Logic input, set high to select the flash mode. 2 EN Enable control logi c input (Active High). 3 PGND Power ground reference. 4 AGND Analog ground reference. 5 LED2 LED channel 2, connected to the LED cathode.* 6 LED1 LED channel 1, connected to the LED cathode.* 7 RFLASH Resistor connection to set Flash mode LED current. 8 RSET Resistor connection to set Movie mode LED current. 9 VIN Power supply input. 10,11 SW Drain connection of low resistance power MOSFET.
12 OVP Over Voltage Protection comparator input
- LED1 or LED2 pin should not be left floating. PIN FUNCTION VIN is the supply voltage input. The device is compatible with supply voltages down to 2.8V and up to 4.2V. Internal under-voltage lockout (UVLO) circuitry will automatically prevent the device from operating whenever the supply falls below 1.9V. For operation up to maximum rated loads a bypass ceramic capacitor of 10µF is recommended between the VIN and GND pins near the device. EN is the enable logic input (active high). When the pin voltage is taken below 0.4V, the device enters shutdown mode, drawing nearly zero current. At pin voltages greater than 1.4V, the device is fully enabled. FLASH is the logic input (active high) used to control Flash mode operation. When the pin voltage is taken above 1.4V, the device transitions from Movie mode to Flash mode. When the pin voltage is taken back below 0.4V, the device returns back to Movie mode operation. RSET, RFLASH pins allow to set the LED current respectively in Movie and Flash mode. These pins, regulated at 1.2V, must be connected to a pull-down resistor tied to ground. The LED current is a function of the resistor value. GND is the ground reference for the driver. The pin must be connected to the ground plane on the PCB. SW pin is the drain terminal of the internal low resistance power switch. The inductor and the Schottky diode anode should be connected to the SW pin. Traces going to the SW pin should be as short as possible with minimum loop area. This pin contains over-voltage circuitry which becomes active above 18V. In the event of an “open-LED” fault condition, the device will enter a low power mode and the SW pin will be clamped to approximately 21V. LED1, LED2 provide the internal regulated current for each of the LED cathodes. These pins enter a high impedance zero current state whenever the device is placed in shutdown mode. In applications with only one string of LEDs, the two LED pins should be tied together. LED pins should not be left floating. OVP is the overvoltage protection input pin. When the pin voltage exc eeds the 1.2V overvoltage threshold OVP), the driver stops switching. The output VOUT then drops down. As soon as the OVP pin voltage falls under the V OVP threshold, the part starts switching again. 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-5021 Rev. B 8 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice. DEVICE OPERATION The device is powered from the input pin VIN. A switching frequency of 1.2MHz is used in Movie mode, when the FLASH input is low. Continuous LED current up to 50mA is controlled by the RSET resistor. For higher load current, the Flash mode is selected by setting the FLASH input pin high. RFLASH now controls the LED current. In flash mode, the driver efficiency is kept high even under high load current by using a lower switching frequency of 900kHz. In movie mode, the higher frequency of 1.2MHz provides a lower noise operation. Overvoltage Protection (OVP) To prevent the SW pin voltage from exceeding the internal switch maximum voltage rating, an overvoltage protection (OVP) function is supported. The OVP pin allows to set the maximum operating voltage on the output VOUT using external resistors R1 and R2. The resistor ratio sets the maximum output voltage as shown in the equation below: R1/R2 = (VOUT MAX /1.2) - 1.2 VOUTMAX should always be higher than the total LED forward voltage ( ΣVf) plus 1.2V. Also VOUT must be less than ΣVf + 8V. ΣVf + 1.2V < VOUTMAX < ΣVf + 8V < 16V If the overvoltage protection is not needed, then the OVP pin should be connected to Ground. In that case, the maximum voltage on the SW pin is set to 17V. BLOCK DIAGRAM Dual Frecuency PWM Controller SW PGND LED2 LED1 OVP AGNDRSET muxRSET RFLASH FLASH EN VIN VIN VOUT CIN COUT RFLASH
2 Current Sink
© Catalyst Semiconductor, Inc. 9 Doc. No. MD-5021 Rev. B Characteristics subject to change without notice.
APPLICATION INFORMATION
The typical application for the CAT4134 is in a camera-equipped cellular phone where the LEDs are used for illumination in flash mode with short duration high-current pulse and in movie m ode with continuous lighter load. In movie mode, the FLASH pin is set low. Note: Hot-plugging the LEDs while the output is fully charged is not recommended. If the LEDs are disconnected, the device should first be powered-down and the output discharged before reconnecting the LEDs to the output and the LED pins. TIMING DIAGRAM LED CURRENT SETTING Flash Mode The enable EN and FLASH logic input signals control the LED current. When both the EN and FLASH inputs are high, the driver is in flash or strobe mode. In this mode, the LED1 and LED2 pin currents are set by the resistor RFLASH and are regulated to 1800 times the current in the RFLASH resistor and follows the equation: LED current = 1800 x 1.2V / RFLASH Movie Mode When the EN input is high and FLASH is low, the driver is in movie mode. In this mode, the LED1 and LED2 pin currents are set by the resistor RSET and are regulated to 360 times the current in the RSET resistor and follows the equation: LED current = 360 x 1.2V / RSET Table 1 lists the various LED currents and the asso- ciated resistor values in movie and flash modes. Table 1. Resistor Selection in Movie and Flash Mode
Doc. No. MD-5021 Rev. B 10 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice. TYPICAL APPLICATIONS The CAT4134 can drive one or two strings of 2 to 3 LEDs in series resulting in combinations of 2, 3, 4, 6 LEDs. The resistor ratio R1/R2 sets the maximum VOUT during an open-LED fault condition and provides the overvoltage protection. For applications with 2 LEDs in series and VOUT MAX at 10V, the ratio R1/R2 is 7. For applications with 3 LEDs in series and VOUT MAX at 13.5V, the ratio R1/R2 is 10.
© Catalyst Semiconductor, Inc. 11 Doc. No. MD-5021 Rev. B Characteristics subject to change without notice. PACKAGE OUTLINE DRAWINGS TDFN 12-Pad 3mm x 3mm, (HV2) (1) (2) Notes: (1) All dimensions are in millimeters. (2) Complies with JEDEC standard MO-229 For current Tape and Reel information, download the PDF file from: http://www.catsemi.com/documents/tapeandreel.pdf. E2P eM R N eb A SIDE VIEW BOTTOM VIEW E D TOP VIEW PIN#1 INDEX AREA PIN#1 ID FRONT VIEW RECOMMENDED LAND PATTERN A L SYMBOL MIN NOM MAX A 0.70 0.75 0.80 A1 0.00 0.02 0.05 A3 0.178 0.203 0.228 b 0.18 0.23 0.30 D 2.90 3.00 3.10 D2 2.30 2.40 2.50 E 2.90 3.00 3.10 E2 1.55 1.70 1.75 e 0.45 BSC L 0.30 0.40 0.50 M 0.25 0.30 0.35 N 0.60 0.70 0.80 P 2.70 3.00 3.10 R2 . 2 5 T Y P
Doc. No. MD-5021 Rev. B 12 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice. EXAMPLE OF ORDERING INFORMATION(1) 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 exampl e is a CAT4134HV2-GT2 (TDFN, NiPdAu, Tape and Reel, 2,000/Reel). (4) For additional package and temperature options, please contact your nearest Catalyst Semiconductor Sales office. Prefix Device # Suffix CAT 4134 HV2 – GT 2 Package HV2: TDFN Product Number Lead Finish Blank: Matte-Tin G: NiPdAu Tape & Reel T: Tape & Reel 2: 2,000/Reel Optional Company ID For Product Top Mark Codes, click here: http://www.catsemi.com/techsupport/producttopmark.asp
REVISION HISTORY
Date Rev. Reason 18-Oct-06 A Initial Issue 13-May-08 B Add TDFN in NiPdAu plated finish. Update Package Outline Drawing. Update Example of Ordering Information. Add MD- to the 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 Quant um 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 surgica l 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 Document No: MD-5021 Fax: 408.542.1200 Revision: B www.catsemi.com Issue date: 05/13 /08