MAX17062 19-1042 Rev 0 10/07 TFT-LCD Step-Up DC-DC Converter General Description Features The MAX17062 is a high-performance step-up DC-DC 90% Efficiency converter that provides a regulated supply voltage for Adjustable Output from V to 20V IN active-matrix thin-film transistor (TFT) liquid-crystal dis- plays (LCDs). The MAX17062 incorporates current- 2.6V to 5.5V Input Supply Range mode, fixed-frequency, pulse-width modulation (PWM) Input Supply Undervoltage Lockout circuitry with a built-in n-channel power MOSFET to achieve high efficiency and fast-transient response. Pin-Programmable 640kHz/1.2MHz Switching Users can select 640kHz or 1.2MHz operation using a Frequency logic input pin (FREQ). The high switching frequencies Programmable Soft-Start allow the use of ultra-small inductors and low-ESR ceramic capacitors. The current-mode architecture pro- Improved EMI vides fast transient response to pulsed loads. A com- FB Regulation Voltage Tolerance < 1% pensation pin (COMP) gives users flexibility in adjusting Small 10-Pin TDFN Package loop dynamics. The 22V internal MOSFET can generate output voltages up to 20V from an input voltage Thermal-Overload Protection between 2.6V and 5.5V. Soft-start slowly ramps the input current and is programmed with an external capacitor. Ordering Information The MAX17062 is available in a 10-pin TDFN package. PIN- PKG PART TEMP RANGE PACKAGE CODE Applications 10 TDFN-EP* MAX17062ETB+T -40C to +85C T1033-2 Notebook Computer Displays (3mm x 3mm) LCD Monitor Panels +Denotes a lead-free package. *EP = Exposed pad. LCD TV Panels T = Tape and reel. Pin Configuration Minimal Operating Circuit V IN V OUT 2.6V TO 5.5V TOP VIEW 10 9 8 7 6 67 LX LX 8 2 FB IN MAX17062 MAX17062 9 5 PGND FREQ 3 4 *EP PGND SHDN 12 3 4 5 10 1 COMP SS AGND EP TDFN (3mm x 3mm) *EP = EXPOSED PAD. 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. EVALUATION KIT AVAILABLE COMP SS FB FREQ SHDN IN PGND LX PGND LXTFT-LCD Step-Up DC-DC Converter ABSOLUTE MAXIMUM RATINGS LX to AGND............................................................-0.3V to +22V Continuous Power Dissipation (T = +70C) A IN, SHDN, FREQ, FB to AGND..............................-0.3V to +7.5V 10-Pin TDFN (derate 24.4mW/C above +70C)..........1951mW COMP, SS to AGND ....................................-0.3V to (V + 0.3V) Operating Temperature Range ...........................-40C to +85C IN PGND to AGND.....................................................-0.3V to +0.3V Junction Temperature......................................................+150C LX Switch Maximum Continuous RMS Current.....................3.2A Storage Temperature Range .............................-65C to +160C Lead Temperature (soldering, 10s) .................................+300C 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 (V = V = 3V, FREQ = 3V, T = 0C to +85C. Typical values are at T = +25C, unless otherwise noted.) (Note 1) IN SHDN A A PARAMETER CONDITIONS MIN TYP MAX UNITS V < 18V 2.6 5.5 OUT Input Voltage Range V 18V < V < 20V 4.0 5.5 OUT Output Voltage Range 20 V IN Undervoltage-Lockout V rising, typical hysteresis is 50mV 2.30 2.45 2.57 V IN Threshold V = 1.3V, not switching 0.3 0.6 FB IN Quiescent Current mA V = 1.0V, switching 1.5 2.5 FB SHDN = AGND, T = +25C 0.01 10.0 A IN Shutdown Current A SHDN = AGND, T = +85C 0.01 A Temperature rising 160 Thermal Shutdown C Hysteresis 20 ERROR AMPLIFIER FB Regulation Voltage Level to produce V = 1.24V 1.23 1.24 1.25 V COMP FB Input Bias Current V = 1.24V 75 150 225 nA FB FB Line Regulation Level to produce V = 1.24V, V = 2.6V to 5.5V 0.01 0.15 %/V COMP IN Transconductance 110 250 450 S Voltage Gain 2400 V/V Shutdown FB Input Voltage SHDN = AGND 0.05 0.10 0.15 V OSCILLATOR FREQ = AGND 500 640 780 Frequency kHz FREQ = IN 1000 1200 1400 Maximum Duty Cycle 88 91 94 % n-CHANNEL MOSFET Current Limit V = 1V, 75% duty cycle, IN = 5V 3.9 4.6 5.3 A FB IN = 5V 100 170 On-Resistance m IN = 3V 125 210 Leakage Current V = 20V 11 20 A LX Current-Sense Transresistance IN = 5V 0.09 0.15 0.25 V/A SOFT-START Reset Switch Resistance 100 Charge Current V = 1.2V 2 4 6 A SS 2 MAX17062