MAX1516A

The MAX1516A includes a highperformance step-up regulator, two linear-regulator controllers, and high-current operational amplifiers for active-matrix thin-film transistor (TFT) liquid-crystal displays (LCDs). Also included is a logic-controlled, highvoltage switch with adjustable delay.On the rising edge of the internal clock, the controller sets a flip-flop, turning on the n-channel MOSFET and applying the input voltage across the inductor. The current through the inductor ramps up linearly, storing energy in its magnetic field.

Features of the MAX1516A are:(1)2.6V to 5.5V input supply range; (2)1.2MHz current-mode step-up regulator; (3)linear-regulator controllers for VGON and VGOFF; (4)high-performance operational amplifiers; (5)logic-controlled, high-voltage switch with adjustable delay; (6)timer-delay fault latch for all regulator outputs; (7)thermal-overload protection; (8)0.6mA quiescent current.The step-up DC-DC converter provides the regulated supply voltage for the panel source driver ICs. The converter is a high-frequency (1.2MHz) current-mode regulator with an integrated 14V n-channel MOSFET that allows the use of ultra-small inductors and ceramic capacitors. It provides fast transient response to pulsed loads while achieving efficiencies over 85%.

The absolute maximum ratings of the MAX1516A can be summarized as:(1)IN, CTL to AGND:-0.3V to + 6V;(2)SUP to AGND:-0.3V to +14V;(3)storage temp:-65 to +150;(4)operating temp:-40 to 100;(5)PGND, BGND to AGND:±0.3V;(6)LX switch maximum continuous RMS output current:1.6A.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.The main step-up regulator employs a current-mode,fixed-frequency PWM architecture to maximize loop bandwidth and provide fast transient response to pulsed loads typical of TFT-LCD panel source drivers.The 1.2MHz switching frequency allows the use of lowprofile inductors and ceramic capacitors to minimize the thickness of LCD panel designs. The integrated high-efficiency MOSFET and the IC's built-in digital soft-start functions reduce the number of external components required while controlling inrush currents.