Texas Instruments TPS54A20

Description

The TPS54A20 is a two-phase, synchronous seriescapacitor buck converter designed for small size, lowvoltage applications from a 12-V input rail. Thistopology uniquely merges a switched capacitor circuitwith a two phase buck converter. Advantages includeautomatic current balancing between the inductors,lower switching losses which enable high frequency(HF) operation, and voltage step-down through theseries capacitor. Small, low profile inductors usedwith the TPS54A20 significantly reduce total solutionarea and height. An adaptive on-time controlarchitecture provides fast transient response andaccurate voltage regulation at up to 10-MHz operatingfrequency. Fixed frequency operation during steadystate is maintained through the use of a phase lockloop (PLL) to lock switching signals to a referenceoscillator.

Features

Two-phase, Synchronous Series Capacitor BuckConverter

• Automatic Current Balancing Between Phases
• 2-MHz to 5-MHz Per Phase Switching Frequency
• 14-ns Minimum On-Time
• 0.51-V to 2-V Output Voltage Range with ±0.5%Feedback Reference Voltage
• Input Overvoltage Lockout for 17-V SurgeProtection
• Adjustable Current Limit with Auto Restart(Hiccup)
• Synchronizes to an External Clock
• Fixed Frequency in Steady State
• Adaptive On-Time Control
• Internal Feedback Loop Compensation
• Internal Gate Drive LDO with External SupplyOption
• EN Pin Allowing for Adjustable Input UVLO
• Selectable Soft-Start Time
• Monotonic Startup with Pre-biased Output
• Output Power Good Indicator (Open Drain)
• Output Overvoltage/Undervoltage Protection

Typical applications

• Low profile/Backside board mounting (< 2 mm height)
• Telecom, base station, and communications Equipment
• Storage, SSD, DDR memory, switches, hubs, routers, and other networking equipment