DESCRIPTION/ORDERING INFORMATION
The TPS65250RHAR features three synchronous wide input range high efficiency buck converters. The converters are designed to simplify its application while giving the designer the option to optimize their usage according to the target application.
The converters can operate in 5-,9-,12-and 15-V systems and have integrated power transistors. The output voltage can be set externally using a resistor divider to any value between 0.8 V and the input supply minus 1 V.Each converter features enable pin that allows a delayed start-up for sequencing purposes, soft start pin that allows adjustable soft-start time by choosing the soft-start capacitor, and a current limit(RLlMx) pin that enables designer to adjust current limit by selecting an external resistor and optimize the choice of inductor. The COMP pin allows optimizing transient versus dc accuracy response with a simple RC compensation.The switching frequency of the converters can either be set with an external resistor connected to ROSC pin or can be synchronized to an external clock connected to SYNC pin if needed. The switching regulators are designed to operate from 300 kHz to 2.2 MHz. Both Bucks 2 and Buck 3 run in-phase and 180 out of phase with Buck 1 to minimize input filter requirements.
TPS65250RHAR features a unique storage and release circuitry for dying gasp mode. The storage capacitor is separated from input capacitor during normal operation. The storage and release circuit will charge the storage capacitor with a controlled circuit to reduce the inrush current from the adaptor supply to a storage voltage of 20V to accumulate as much energy as possible taking advantage of the 2 CV2 feature.
FEATURES
· Wide Input Supply Voltage Range (4.5V-18V)
·0.8V,1% Accuracy Reference
· Continuous Loading:3A(Buck 1), 2A(Buck 2 and 3)
· Maximum Current:3.5A(Buck 1), 2.5A(Buck 2 and 3)
· Adjustable Switching Frequency 300 kHz-2.2 MHz Set By External Resistor
· External Synchronization Pin for Oscillator
· External Enable/Sequencing and Soft Start Pins
· Adjustable Current Limit Set By External Resistor
·Soft Start Pins
·Current-Mode Control With Simple Compensation Circuit
·Power Good and Reset Generator
·Storage and Release Circuit Optimized for Reduction of Storage Capacitance in Dying Gasp Mode (Option)
·Low Power Mode Set By External Signal
·QFN Package,40-Pin 6 mm x6mm RHA
APPLICATIONS
·XDSL/xPON Modems
·Cable Modems
·Power Line Modem
·Home Gateway and Access Point Networks
·Wireless Routers
·Set Top Box
(Picture:Pinout / Diagram)
