Evaluates: MAX16835/MAX16836 19-4408 Rev 0 1/09 MAX16836 Evaluation Kit General Description Features The MAX16836 evaluation kit (EV kit) demonstrates a 6.5V to 40V Supply Voltage Range current-controlled, high-output-current LED driver Selectable 150mA, 250mA, or 350mA Output based on the MAX16836 current regulator. The EV kit is Current capable of supplying regulated output currents of up to 350mA and runs at supply voltages between 6.5V to 5V Regulated Output with 4mA Source Capability 40V. Wide-Range Dimming Control with PWM The MAX16836 EV kit features a PWM dimming control, Lead(Pb)-Free and RoHS Compliant user-selectable three-level output-current setting, and a 5V regulated output, which supplies up to 4mA of out- Fully Assembled and Tested put current. The MAX16836 EV kit also evaluates the MAX16835 IC contact the factory for a free sample of the MAX16835 IC. Ordering Information PART TYPE MAX16836EVKIT+ EV Kit +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION CS+, V5 2 Test points 0.82 1%, 1/4W resistor (0805) R2 1 Susumu RP2012T-R82-F 0.1F 10%, 50V X7R ceramic R3, R4 2 100k 5% resistors (0603) capacitors (0603) C1, C2 2 Murata GRM188R71H104K 350mA adjustable high-brightness TDK C1608X7R1H104K U1 1 LED driver (16 TQFN) Maxim MAX16836ATE+ JU1 1 2-pin header JU2 1 3-pin header 2 Shunts 0.56 1%, 1/4W resistor (0805) 1 PCB: MAX16836 Evaluation Kit+ R1 1 Susumu RP2012T-R56-F Component Suppliers SUPPLIER PHONE WEBSITE Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com Susumu International USA 208-328-0307 www.susumu-usa.com TDK Corp. 847-803-6100 www.component.tdk.com Note: Indicate that you are using the MAX16836 when contacting these component suppliers. 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.MAX16836 Evaluation Kit els of output LED currents by setting jumper JU2 (see Quick Start Table 1 for jumper settings). The MAX16836 EV kit also Recommended Equipment includes a connection for the 5V regulated output and Before beginning, the following equipment is needed: access to the on-board current-sense resistor. 0 to 30V or above, 0.5A power supply Output Current Setting The output current can be adjusted by replacing resis- Procedure tors R2 or R3 with values calculated using the following The MAX16836 EV kit is fully assembled and tested. equation: Follow the steps below to verify board operation. Caution: Do not turn on the power supply until all V SENSE connections are completed. R = SENSE I LED 1) Connect a DC power supply (0 to 30V or above, 0.5A) to VIN. where R is the external current-sense resistance SENSE between CS+ and GND, I is the desired output cur- LED 2) Verify that a shunt is not installed across jumper rent, and V is 200mV (typ). SENSE JU1 to enable U1. 3) Verify that a shunt is installed across pins 1-2 of PWM Dimming jumper JU2 to select 350mA output current. The PWM dimming controls the LED brightness by adjusting the duty cycle of the PWM input signal con- 4) Connect a 350mA-rated LED between LED+ and nected to the DIM input. A high at the DIM input turns LED-. on the output current and a low turns off the output cur- 5) Turn on the power supply and increase the input rent. Connect a signal with peak amplitude between 5V voltage to above 6.5V. The LED should glow with and 40V, frequency between 100Hz and 2kHz, and full brightness. Measure the LED current, which vary the duty cycle to adjust the LED brightness. LED should be 350mA 3.5%. brightness increases when duty cycle increases and 6) Increase the supply voltage and measure the LED vice versa. Duty cycle can be as low as 10% even at a current, which should be 350mA 3.5%. Note that PWM frequency of 2kHz. the maximum voltage drop between IN and OUT 5V Regulated Output should be ~7V to limit the maximum power dissipa- The 5V regulator can be used to power other compo- tion to approximately 2.5W. nents from the V5 test point. The 5V output supplies up 7) Measure the voltage across V5, which should be to 4mA of current. 5V 4%. Jumper Selection Detailed Description of Hardware Two-pin jumper JU1 controls the EN pin of the The MAX16836 EV kit demonstrates a high-output- MAX16836 and enables or disables the device. Three- current LED driver with accurate current control based pin jumper JU2 selects between three different output on the MAX16836 current regulator. The MAX16836 EV current settings. Table 1 lists the jumper options. kit is capable of supplying regulated output currents of up to 350mA and runs at supply voltages between 6.5V to 40V. If the supply voltage is above the LED Table 1. Jumper JU1 and JU2 Functions operating voltage by more than 7V, the maximum out- put current should be limited to prevent the device SHUNT POSITION AND FUNCTION JUMPER from entering into thermal shutdown due to excessive 1-2 (installed) 2-3 Open power dissipation. JU1 U1 disabled U1 enabled* The MAX16836 EV kit features PWM dimming to control JU2 350mA* 250mA 150mA the LED brightness by varying the duty cycle of the *Default position. PWM input signal. Users can select between three lev- 2 Evaluates: MAX16835/MAX16836