CAT4238 LED Driver, Boost, 10 LED, series Description The CAT4238 is a DC/DC stepup converter that delivers an accurate constant current ideal for driving LEDs. Operation at a fixed www.onsemi.com switching frequency of 1 MHz allows the device to be used with small value external ceramic capacitors and inductor. LEDs connected in series are driven with a regulated current set by the external resistor 5 R . LED currents up to 40 mA can be supported over a wide range of 1 1 input supply voltages up to 5.5 V, making the device ideal for battery TSOT23 powered applications. The CAT4238 highvoltage output stage is TD SUFFIX CASE 419AE perfect for driving midsize and large panel displays containing up to ten white LEDs in series. LED dimming can be done by using a DC voltage, a logic signal, or PIN CONNECTIONS a pulse width modulation (PWM) signal. The shutdown input pin 1 allows the device to be placed in powerdown mode with zero VIN SW quiescent current. GND In addition to thermal protection and overload current limiting, the device also enters a very low power operating mode during Open SHDN FB LED fault conditions. The device is housed in a low profile (1 mm (Top View) max height) 5lead thin SOT23 package for space critical applications. MARKING DIAGRAM Features Drives High Voltage LED Strings (38 V) Up to 87% Efficiency MUYM Low Quiescent Ground Current 0.6 mA Adjustable Output Current MU = Specific Device Code 1 MHz Fixed Frequency Low Noise Operation Y = Production Year (Last Digit) Soft Start Inrush Current Limiting M = Production Month Shutdown Current Less than 1 A (19 (JanSep), O, N, D (OctDec)) Open LED Overvoltage Protection Automatic Shutdown at 1.9 V (UVLO) ORDERING INFORMATION Thermal Overload Protection Device Package Shipping Thin SOT23 5lead (1 mm Max Height) CAT4238TDGT3 TSOT23 3,000/ These Devices are PbFree, Halogen Free/BFR Free and are RoHS (PbFree) Tape & Reel Compliant Green* * Lead Finish NiPdAu Applications GPS Navigation Systems Portable Media Players Handheld Devices, Digital Cameras Portable Game Machines Semiconductor Components Industries, LLC, 2016 1 Publication Order Number: April, 2016 Rev. 5 CAT4238/DCAT4238 L D V V IN OUT 47 H C C 2 1 4.7 F 0.22 F SW VIN CAT4238 V = 300 mV FB OFF ON FB 20 mA SHDN GND R 1 15 L: Sumida CDC5D23B470 D: Central CMDSH054 C2: Taiyo Yuden UMK212BJ224 (rated 50 V) Figure 1. Typical Application Circuit Table 1. ABSOLUTE MAXIMUM RATINGS Parameters Ratings Units V , FB voltage 0.3 to +7 V IN SHDN voltage 0.3 to +7 V SW voltage (Note 1) up to 60 V Storage Temperature Range 65 to +160 C Junction Temperature Range 40 to +150 C Lead Temperature 300 C Stresses exceeding those listed in the Maximum Ratings table may damage the device. If any of these limits are exceeded, device functionality should not be assumed, damage may occur and reliability may be affected. 1. The SW pin voltage is rated up to 39 V for external continuous DC voltage. Table 2. RECOMMENDED OPERATING CONDITIONS Parameters Range Units V up to 5.5 V IN SW pin voltage 0 to 38 V Ambient Temperature Range 40 to +85 C Functional operation above the stresses listed in the Recommended Operating Ranges is not implied. Extended exposure to stresses beyond the Recommended Operating Ranges limits may affect device reliability. NOTE: Typical application circuit with external components is shown above. www.onsemi.com 2