NCP1593BMNTWG

The NCP1593 is a fixed 1 MHz, high−output−current, synchronous PWM converter that integrates a low−resistance, high−side P−channel MOSFET and a low−side N−channel MOSFET. The NCP1593 utilizes internally compensated current mode control to provide good transient response, ease of implementation and excellent loop stability. It regulates input voltages from 4.0 V to 5.5 V down to an output voltage as low as 0.6 V and is able to supply up to 3 A of load current. The NCP1593 includes an internally fixed switching frequency (FSW), and an internal soft−start to limit inrush current. Other features include cycle−by−cycle current limiting, 100% duty cycle operation, short− circuit protection, power saving mode and thermal shutdown. The NCP1593 is a synchronous PWM controller that incorporates all the control and protection circuitry necessary to satisfy a wide range of applications. The NCP1593 employs current mode control to provide fast transient response, simple compensation, and excellent stability. The features of the NCP1593 include a precision reference, fixed 1 MHz switching frequency, a transconductance error amplifier, an integrated high−side P−channel MOSFET and low−side N−Channel MOSFET, internal soft−start, and very low shutdown current. The protection features of the NCP1593 include internal soft−start, pulse−by−pulse current limit, and thermal shutdown. The NCP1593 incorporates an internal reference that allows output voltages as low as 0.6 V. The tolerance of the internal reference is guaranteed over the entire operating temperature range of the controller. The reference voltage is trimmed using a test configuration that accounts for error amplifier offset and bias currents. A fixed precision oscillator is provided. The oscillator frequency range is 1 MHz with ±13% variation. The transconductance error amplifier’s primary function is to regulate the converter’s output voltage using a resistor divider connected from the converter’s output to the FB pin of the controller, as shown in the applications schematic. If a Fault occurs, the amplifier’s output is immediately pulled to GND and PWM switching is inhibited. To limit the startup inrush current, a soft−start circuit is used to ramp up the reference voltage from 0 V to its final value linearly. This soft−start time is internally set to a typical value of 500 μs, or it can be externally adjusted by adding a capacitor (C_SS) from the SS pin to GND. The maximum allowable C_SS is 10 nF. The NCP1593 includes low R_DS(on), both high−side P−channel and low−side N. −channel MOSFETs capable of delivering up to 3.0 A

Applications

• Set−Top Boxes
• DVD Drives and HDD
• LCD Monitors and TVs
• Cable Modems
• USB Modems
• Telecom/Networking/Datacom Equipment

Key features

• Wide Input Voltage Range: from 4.0 V to 5.5 V
• Internal 90 mΩ High−Side P−Channel MOSFET and 60 mΩ Low−Side N−Channel MOSFET
• Fixed 1 MHz Switching Frequency
• Cycle−by−Cycle Current Limiting
• Hiccup Mode Short−Circuit Protection
• Overtemperature Protection
• Internal Soft−Start
• Start−up with Pre−Biased Output Load
• Adjustable Output Voltage Down to 0.6 V
• Diode Emulation During Light Load
• 100% Duty Cycle Operation to Extend the Battery Life
• These are Pb−Free Devices