CAT4237EVAL2EVB CAT4237 High Voltage White LED Driver Evaluation Board User s Manual CAT4237EVAL2EVB The board also demonstrates the CAT4237 shutdown Test points T1 to T10 are available to apply the external mode and LED brightness control by using an external voltages/signal generator or to measure the output PWM signal or DC voltage. Resistors R3 and R5 voltages/signals provided by CAT4237. (R5 soldered on board by the user) are used to adjust the The component placement and the board picture are LED current using the dimming control with an external shown in Figure 2. Table 1 presents the component list for applied DC voltage on the FB pin. The ON/OFF operation this evaluation board. and dimming control can be selected using the jumper options for the J1 connector. Figure 2. CAT4237EVAL2 Board Table 1. CAT4237EVAL2 EVAL BOARD LIST OF COMPONENTS Name Manufacturer Description Part Number Units U1 Catalyst CMOS White LED Driver, TSOT23 5pin CAT4237TSI 1 C1 Taiyo Yuden (or Panasonic) Ceramic Capacitor 4.7 F/6.3 V, X5R, JMK212BJ475 1 Size 0805 (or DigiKey PCC2315CTND) C2 Taiyo Yuden (or Kemet) Ceramic Capacitor 0.22 F/50 V, X5R(X7R) (C1206C224K5RACTU) 1 L1 Sumida (or TDK) Inductor 33 H, Low DCR, High Current CDRH3D16330 1 or VLCF4018T330MR422 D1 Central Schottky Diode, Low VF, High Current, CMDSH054 1 SOD323 R1 Yageo SMT Resistor 1/16 W, 6.81 , 0603 DigiKey 3116.81HCTND 1 R2 Bourns Trimmer Pot, 1/4, 100 3329W101ND (or equiv) 1 R3 Yageo SMT Resistor 1/16 W, 1.0 k , 0603 DigiKey 3111.0KHCTND 1 R4 Yageo SMT Resistor 1/16 W, 200 , 0603 DigiKey 311200KHCTND 1 R5 Yageo Metal Film Resistor 1/16 W, 10 k DigiKey 10.0KXBKND 1 (Not Soldered on Board) L1 to L8 Nichia White LED, SMT NSCW100 or NSCW335 8 J1 6pin Header Connector, 0.1, Single Strip DigiKey S101206ND 1 (or equiv) J2 to J4 2pin Header Connector, 0.1, Single Strip DigiKey S101202ND 3 (or equiv) T1 to T10 Pin Receptacle (Test Points) 0149015013014040 10 (or equiv)