TPS65261-1RHBR

The TPS65261 and TPS65261-1 are monolithic triple synchronous step-down (buck) converters with 3A/2A/2A output current. The wide input supply voltage range of 4.5V to 18V covers most intermediate bus voltages operating from 5V, 9V, 12V, or 15V power buses. The converter uses constant-frequency peak current mode control, designed to simplify the application while enabling designers to optimize the system for target applications. The switching frequency is adjustable from 250kHz to 2MHz via an external resistor. The 180° out-of-phase operation between Buck1 and Buck 2/3 (Buck2 and Buck3 operate in phase) minimizes input filter requirements. When the MODE pin is connected to V7V and the EN1/2/3 pins are configured, the TPS65261 and TPS65261-1 feature an automatic power-up sequencing. The device also features an open-drain RESET signal for power-down monitoring. Under light load conditions, the TPS65261 automatically operates in pulse skip mode (PSM), while the TPS65261-1 operates in forced continuous conduction mode (FCC). PSM improves efficiency by reducing switching losses at light load, while FCC reduces noise sensitivity and RF interference. The device features overvoltage protection, overcurrent and short-circuit protection, and overtemperature protection. The power-good pin is asserted whenever any output voltage falls outside the regulated range.

Applications

• Digital Television (DTV)
• Set-Top Boxes
• Home Gateway and Access Point Networks
• Wireless Routers
• Security Surveillance Point-of-Sale (POS) Machines

Key features

• Operating input supply voltage range (4.5V to 18V)
• Feedback reference voltage 0.6V ±1%
• Maximum continuous output current 3A/2A/2A
• Adjustable clock frequency 250kHz to 2MHz
• Dedicated enable and soft-start pins for each buck converter
• Automatic power-up/power-down sequencing
• Pulse Skip Mode (PSM) under light-load conditions (TPS65261 only)
• Output voltage power-good indicator
• Input voltage power-fail indicator
• Thermal overload protection