Evaluates: MAX16839 19-4942 Rev 1 5/10 MAX16839 Evaluation Kit General Description Features The MAX16839 evaluation kit (EV kit) demonstrates S Three Independent Channels for Driving three separate high-voltage, single-channel, linear high- High-Brightness LEDs brightness LED (HB LED) drivers using the MAX16839 S 100mA LED Current per Channel IC. This EV kit is configured to supply an HB LED current S Three Independent PWM Inputs of 100mA per channel and operates from a 5V to 40V rated power supply providing up to 300mA. The EV kit S PWM Dimming Control Up to 10kHz can withstand a 45V automotive load-dump condition. S Operates from a 5V to 40V Supply An input switch is included to evaluate pulse-width- S Supply Input Chopper Circuit modulation (PWM) driving with supply chopping. S Capability for Cascading Multiple Kits The EV kit eases evaluation of the MAX16839 PWM S Proven PCB and Thermal Design dimming-control feature by providing three indepen- dent PWM inputs to all three channels. Each PWM input S Fully Assembled and Tested accepts a digital signal up to 10kHz. Additionally, mul- tiple EV kits can be cascaded by using the MAX16839 Ordering Information FLTS signals. An input common-mode choke is also PART TYPE provided to facilitate EMI immunity testing. MAX16839EVKIT+ EV Kit +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION 1FF Q10%, 50V X7R ceramic 60V 1.25A p-channel MOSFET C1 1 capacitor (0805) (SOT23) P1 1 Murata GRM21BR71H105K Fairchild FDN5618P (Top Mark: 618) 0.022FF Q10%, 50V X7R ceramic C2, C3, C4 3 capacitors (0805) 65V 100mA npn transistor Murata GRM216R71H223K (SOT23) Central Semi BC846A TR 0.1FF Q10%, 50V X7R ceramic Q1 1 (Top Mark: 1A) or C5, C6, C7 3 capacitors (0805) Fairchild BC846AMTF Murata GCM21BR71H104K (Top Mark: 8AA) 60V, 1A Schottky diode (SMA) R1, R3, R5 3 4.12I Q1% resistors (0603) Central Semi CMSH1-60M LEAD D1 1 R2, R4, R6 3 2.05I Q1% resistors (0603) FREE R7, R9, R10 3 10kI Q5% resistors (1206) (Top Mark: CS60M) R8 1 2.2kI Q5% resistor (2010) 15V Q 5%, 250mW zener diode Programmable LED current (SOD523) regulators (6 TDFN-EP*) D2 1 Central Semi CMOZ15V LEAD U1, U2, U3 3 Maxim MAX16839ATT+ FREE (Pkg. Code: T633+2) (Top Mark: H0) 11 Shunts (JU1JU11) JU1, JU2, JU3 3 3-pin headers PCB: MAX16839 EVALUATION JU4JU11 8 2-pin headers 1 KIT+ 80V, 500mA common-mode choke L1 1 *EP = Exposed pad. TDK ZJYS81R5-2P24-G01 Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.MAX16839 Evaluation Kit Component Suppliers SUPPLIER PHONE WEBSITE Central Semiconductor Corp. 631-435-1110 www.centralsemi.com Fairchild Semiconductor 888-522-5372 www.fairchildsemi.com Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com TDK Corp. 847-803-6100 www.component.tdk.com Note: Indicate that you are using the MAX16839 when contacting these component suppliers. 8) Enable the power-supply output. Quick Start 9) Verify that the attached LEDs are illuminated. Required Equipment 5V to 40V, 500mA adjustable DC power supply Detailed Description of Hardware Three series-connected HB LED strings rated no The MAX16839 EV kit demonstrates three separate high- less than 100mA and a maximum forward voltage voltage, single-channel, linear HB LED drivers. Each lin- of 39V ear current driver circuit uses a MAX16839 IC in a 6-pin See the LED Load Configuration section for more TDFN surface-mount package with an exposed pad information for enhanced thermal dissipation. On the EV kit, each driver circuit is configured to supply an HB LED cur- Procedure rent of 100mA per channel at 5% current accuracy. The The MAX16839 EV kit is fully assembled and tested. MAX16839 ICs control the HB LED current by maintain- Follow these steps to verify board operation. Caution: ing a 203mV (typ) drop across each channels external Do not turn on the power supply until all connections sense resistors (R1 or R2 for channel 1, R3 or R4 for are completed. channel 2, and R5 or R6 for channel 3). Additionally, 1) Verify that shunts are installed on pins 1-2 of jumpers each channel can be reconfigured to provide down to JU1, JU2, and JU3 (100mA operation). 50mA of current. 2) Verify that shunts are not installed on jumpers The EV kit operates from a 5V to 40V rated power sup- JU4JU10 (independent operation). ply providing up to 300mA and the EV kit can with- stand a 45V load-dump condition. The input supply is 3) Verify that a shunt is installed on jumper JU11 filtered by common-mode choke L1 and capacitor C1, (bypass chopper circuit). while battery-reverse protection is provided by diode 4) Set the power-supply output to 12V and disable the D1. The input supply chopper circuit is comprised of output. If the total forward voltage of the HB LED p-channel MOSFET P1, biasing resistor/diode pair R7/ string is > 6.5V, ensure that the input supply rises in D2, and switching transistor Q1. See the Chopper-Circuit less than 14Fs, or connect the FLTS output to ground Operation section for more information on using the to disable the turn-off in case of fault feature. The IC chopper circuit. can otherwise latch in fault condition at startup. The MAX16839 PWM dimming-control feature can be 5) Connect the power-supply ground to the PGND PCB evaluated with an independent PWM input on each of pad. the three channels. Each PWM input accepts a digital 6) Connect the power-supply positive output to the VIN signal up to 10kHz at the DIM1, DIM2, or DIM3 and PCB pad. GND PCB pads. Additionally, each PWM input functions as an active-high enable for the corresponding chan- 7) Connect each HB LED string as follows: nel. Multiple EV kits can be cascaded using the FLTS1, Channel 1: Connect an HB LED string anode to FLTS2, FLTS3, and GND PCB pads and configuring the the LED1+ PCB pad and the cathode to the LED1- proper jumpers. Jumpers JU8, JU9, and JU10 disable PCB pad. the MAX16839 fault-detection features. Channel 2: Connect an HB LED string anode to Each MAX16839 IC features an exposed pad that uses the LED2+ PCB pad and the cathode to the LED2- the top-layer and bottom-layer PCB copper as a heat-sink. PCB pad. For a single-layer design, the top-layer copper would only Channel 3: Connect an HB LED string anode to be required from a thermal-design perspective. The EV the LED3+ PCB pad and the cathode to the LED3- kit PCB uses 2oz copper for optimum thermal dissipation. PCB pad. 2 Evaluates: MAX16839