MAX783 Datasheet | Maxim Integrated

Description The MAX783 is a system-engineered power-supply controller for notebook puters or similar battery-powered equipment. It provides two high-performance step-down (buck) pulsewidth modulators (PWMs) for +3.3V/+5V and dual PCMCIA VPP outputs powered by an integral flyback winding controller. Other functions include dual, low-dropout, micropower linear regulators for CMOS/RTC back up, and two precision lowbattery-detection parators. High efficiency (95% at 2A, greater than 80% at loads from 5m A to 3A) is achieved through synchronous rectification and PWM operation at heavy loads, and Idle-Mode TM operation at light loads. The MAX783 uses physically small ponents, thanks to high operating frequencies (300k Hz/200k Hz) and a new current-mode PWM architecture that allows for output filter capacitors as small as 30µF per ampere of load. Line- and load-transient responses are terrific, with a high 60k Hz unity-gain crossover frequency that allows output transients to be corrected within four or five clock cycles. Low system cost is achieved through a high level of integration and the use of low-cost external N-channel MOSFETs. The integral flyback winding controller provides a low-cost, +15V high-side output that regulates even in the absence of a load on the main output. Other features include low-noise, fixed-frequency PWM operation at moderate to heavy loads and a synchronizable oscillator for noise-sensitive applications such as electromagnetic pen-based systems and municating puters. The MAX783 is similar to the MAX782, except the flyback winding is on the 3.3V inductor instead of the 5V inductor, the VPP outputs can be optionally programmed to 3.3V, and the device may be pletely shut down. ______________Ordering Information PART MAX783CBX MAX783RCBX TEMP. RANGE 0°C to +70°C 0°C to +70°C PIN-PACKAGE 36 SSOP 36 SSOP VOUT 3.3V 3.45V Ordering Information continued on last page. __________________Pin Configuration TOP VIEW ON3 1 SHDN 2 D1 3 D2 4 VH 5 Q2 6...