High-Efficiency Step-Up Current Regulator for LEDsABSOLUTE MAXIMUM RATINGS VCC, SHDN to GND ..-0.3V to +6V Operating Temperature Range ...-40°C to +85°C EXT, FB, CS, ADJ, REF to GND..-0.3V to (VCC + 0.3V) Junction Temperature ..+150°C GND to PGND...±0.3V Storage Temperature Range ...-65°C to +150°C Continuous Power Dissipation (TA = +70°C) Lead Temperature Range (soldering, 10s)..+300°C 10-Pin µMAX (derate 5.6mW/°C above +70°C) ..444mW Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VCC = +3.3V, TA = 0°C to +85°C , unless otherwise noted. Typical values are at TA = +25°C.) PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS Supply Voltage VCC 2.7 5.5 V Quiescent Supply Current ICC VFB = 0.3V 260 500 µA Undervoltage Lockout Rising edge 2.25 2.4 2.55 V Undervoltage Hysteresis 80 mV MAX1698/MAX1698A ADJ = REF 285 300 315 FB Regulation Voltage VFB mV VADJ = 100mV 18 24 30 MAX1698A 2.0 2.4 2.8 CS Trip Current FB = GND A MAX1698 0.8 1.5 2.5 CS Input Current ICS 0.8 ARMS Minimum Off Time tOFF(MIN) FB = GND, ADJ = REF 0.8 1.0 1.2 µs Maximum On Time tON(MAX) FB = GND, ADJ = REF, CS = GND 10 15 20 µs ADJ Start Threshold 30 50 70 mV ADJ Input Range VADJ 0.03 REF V FB Input Bias Current IFB VFB = 300mV -15 15 nA ADJ Input Bias Current IADJ ADJ = REF -50 50 nA Shutdown Supply Current SHDN = GND 0.01 1 µA REF Output Voltage VREF IREF = 0 1.20 1.25 1.30 V REF Load Regulation ∆VREF IREF = 0 to 150µA -2 -25 mV REF Short-Circuit Current REF = GND 0.45 1 mA REF Power-Supply Rejection PSRR V Ratio CC = 2.7V to 5.5V +0.3 +2 mV/V EXT Driver Sink/Source Current VCC = 5V, EXT = 2V 0.2 A EXT Driver On-Resistance VCC = 5V 8 Ω SHDN Input High Voltage VIH VCC = 2.7V to 5.5V 2 V SHDN Input Low Voltage VIL VCC = 2.7V to 5.5V 0.8 V SHDN Input Bias Current ISHDN VCC = 2.7V to 5.5V -1 1 µA 2_______________________________________________________________________________________