CAV4201 LED Driver, 350 mA, Step-Down Converter Description The CAV4201 is a high efficiency stepdown converter optimized to drive high current LEDs. A patented switching control algorithm CAV4201 Table 1. ABSOLUTE MAXIMUM RATINGS Parameters Ratings Units VBAT, SW, CTRL 0.3 to +40 V RSET 0.3 to +5 V Switch SW peak current 1 A Storage Temperature Range 65 to +160 C Junction Temperature Range 40 to +150 C Lead Temperature 300 C Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. Table 2. RECOMMENDED OPERATING CONDITIONS Parameters Ratings Units VBAT voltage (Notes 1, 2) 6.5 to 36 (Note 1) V SW voltage 0 to 36 V Ambient Temperature Range 40 to +125 C LED Current 50 to 350 mA Switching Frequency 50 to 1000 kHz 1. The VBAT pin voltage should be at least 3 V greater than the total sum of the LED forward voltages in order to operate at nominal LED current. 2. During powerup, the slew rate of the input supply should be greater than 1 s for every 5 V increase of VBAT. Table 3. ELECTRICAL CHARACTERISTICS (V = 13 V, ambient temperature of 25C (over recommended operating conditions unless otherwise specified)) IN Symbol Parameter Conditions Min Typ Max Units I Operating Supply Current on VBAT pin 0.4 1 mA Q I Idle Mode Supply Current on VBAT pin CTRL = GND 90 A SD V RSET Pin Voltage 2 LEDs with I = 300 mA 1.15 1.2 1.25 V FB LED I Programmed LED Current R1 = 33 k 100 mA LED R1 = 10 k 270 300 330 350 R1 = 8.25 k V CTRL Voltage for 100% Brightness 2.6 3.1 V CTRL FULL V CTRL Voltage to Enable LEDs LED enable voltage threshold 0.9 1.2 V CTRL EN V CTRL Voltage to Shutdown LEDs LED disable voltage threshold 0.4 0.9 V CTRL SD I CTRL pin input bias V = 3 V 40 80 A CTRL CTRL V = 12 V 200 CTRL R Switch On Resistance I = 300 mA 0.9 1.5 SW SW T Thermal Shutdown 150 C SD T Thermal Hysteresis 20 C HYST Efficiency Typical Application Circuit 86 %