30V, 1.2A Step-down High Brightness LED Driver with 5000:1 Dimming China Resources Powtech (Shanghai) Limited WWW.CRPOWTECH.COM Page 1 PT4115_DS Rev EN_2.6 PT4115 GENERAL DESCRIPTION The PT4115 is a continuous conduction mode inductive step-down converter, designed for driving single or multiple series connected LED efficiently from a voltage source higher than the total LED chain voltage. The device operates from an input supply between 8V and 30V and provides an externally adjustable output current of up to 1.2A. Depending upon the supply voltage and external components, the PT4115can provide more than 30 watts of output power. The PT4115 includes the power switch and a high-side output current sensing circuit, which uses an external resistor to set the nominal average output current, and a dedicated DIM input accepts either a DC voltage or a wide range of pulsed dimming. Applying a voltage of 0.3V or lower to the DIM pin turns the output off and switches the device into a low current standby state. The PT4115 is available in SOT89-5 and ESOP8 packages. FEATURES ? Simple low parts count ? Wide input voltage range: 8V to 30V ? Up to 1.2A output current ? Single pin on/off and brightness control using DC voltage or PWM ? Up to 1MHz switching frequency ? Typical 5% output current accuracy ? Inherent open-circuit LED protection ? High efficiency (up to 97%) ? High-Side Current Sense ? Hysteretic Control: No Compensatio ? Adjustable Constant LED Current ? ESOP8 package for large output power application APPLICATIONS ? Low voltage halogen replacement LEDs ? Automotive lighting ? Low voltage industrial lighting ? LED back-up lighting ? Illuminated signs ? SELV lighting ? LCD TV backlighting ORDERING INFORMATION PACKAGE TEMPERATURE RANGE ORDERING PART NUMBER TRANSPORT MEDIA MARKING SOT89-5 -40 oC to 85 oC PT4115-89E Tape and Reel 1000 units PT4115 xxxxxX ESOP8 -40 oC to 85 oC PT4115-SOH Tape and Reel 2500 units PT4115 xxxxxX Note: TYPICAL APPLICATION CIRCUIT xxxxxX Assembly Factory Code Lot Number 30V, 1.2A Step-down High Brightness LED Driver with 5000:1 Dimming China Resources Powtech (Shanghai) Limited WWW.CRPOWTECH.COM Page 2 PT4115_DS Rev EN_2.6 PT4115 PIN ASSIGNMENT PIN DESCRIPTIONS PIN No. PIN NAMES DESCRIPTION 1 SW Switch Output. SW is the drain of the internal N-Ch MOSFET switch. 2 GND Signal and power ground. Connect directly to ground plane. 3 DIM Logic level dimming input. Drive DIM low to turn off the current regulator. Drive DIM high to enable the current regulator. 4 CSN Current sense input 5 VIN Input Supply Pin. Must be locally bypassed. - Exposed PAD Internally connected to GND. Mount on board for lower thermal resistance. ESOP8 4,5 NC No connection ABSOLUTE MAXIMUM RATINGS (note1) SYMBOL ITEMS VALUE UNIT VIN Supply Voltage -0.345 V SW Drain of the internal power switch -0.345 V CSN Current sense input (Respect to VIN) +0.3(-6.0) V DIM Logic level dimming input -0.36 V ISW Switch output current 1.5 A PDMAX Power Dissipation (Note 2) 1.5 W PTR Thermal Resistance, SOT89-5 JA 45 oC /W PTR Thermal Resistance, ESOP8 JA 40 oC /W TJ Operation Junction Temperature Range -40 to 150 oC TSTG Storage Temperature -55 to 150 oC ESD Susceptibility (Note 3) 2 kV 1 2 3 4 5 6 7 8 PT4115 CSN VIN SW NCNC GNDP GNDA DIM ESOP8 30V, 1.2A Step-down High Brightness LED Driver with 5000:1 Dimming China Resources Powtech (Shanghai) Limited WWW.CRPOWTECH.COM Page 3 PT4115_DS Rev EN_2.6 PT4115 RECOMMENDED OPERATING RANGE SYMBOL ITEMS VALUE UNIT VIN VDD Supply Voltage 0 30 V TOPT Operating Temperature -40 to +85 oC Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Recommended Operating Range indicates conditions for which the device is functional, but do not guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which guarantee specific performance limits. This assumes that the device is within the Operating Range. Specifications are not guaranteed for parameters where no limit is given, however, the typical value is a good indication of device performance. Note 2: The maximum power dissipation must be derated at elevated temperatures and is dictated by TJMAX, JA, and the ambient temperature TA. The maximum allowable power dissipation is PDMAX = (TJMAX - TA)/ JA or the number given in Absolute Maximum Ratings, whichever is lower. Note 3: Human body model, 100pF discharged through a 1.5k resistor. ELECTRICAL CHARACTERISTICS (Note 4, 5) The following specifications apply for VIN=12V, TA=25 oC, unless specified otherwise. SYMBOL ITEMS CONDITIONS Min. Typ. Max. UNIT VIN Input Voltage 8 30 V VUVLO Under voltage lock out VIN falling 6.8 V VUVLO, HYS UVLO hysterisis VIN rising 500 mV FSW Max. Switching Frequency 1 MHz Current Sense A type 95 98 101 mV VCSN Mean current sense threshold voltage VIN-VCSN B type 99 102