TPS40400RHLT.A中文资料德州仪器数据手册PDF规格书

1 Features

1• Input Operating Voltage Range: 3 V to 20 V

• PMBus Enabled Analog Controller

• Reference 600 mV ± 1%

• Remote Voltage Sense Amplifier

• Internal 6-V Regulator and 6-V Gate Drive

• Programmable Overcurrent Protection

• Inductor Resistance or Series Resistance Used

for Current Sensing

• Programmable Switching Frequency: 200 kHz to 2

MHz

• Powergood Indicator

• Thermal Shutdown

• Programmable Soft-Start

• Internal Bootstrap Diode

• Prebias Output Safe

• 24-Pin QFN Package

2 Applications

• Smart Power Systems

• Power Supply Modules

• Communications Equipment

• Computing Equipment

3 Description

The TPS40400 is a cost-optimized flexible

synchronous buck controller that operates from a

nominal 3-V to 20-V supply. This controller is an

analog PWM controller that allows programming and

monitoring through the PMBus™ interface. Flexible

features found on this device include programmable

soft-start time, programmable short circuit limit, and

programmable undervoltage lockout (UVLO).

An adaptive anti-cross conduction scheme is used to

prevent shoot through current in the power FETs.

Gate drive voltage is 6 V to better enhance the power

FETs for reduced losses. Short circuit detection

occurs by sensing the voltage drop across the

inductor or across a resistor placed in series with the

inductor. A PMBus programmable threshold is

compared to this voltage and is used to detect

overcurrent. When the overcurrent threshold is

reached, a pulse by pulse current limit scheme is

used to limit the current to acceptable levels. If the

overcurrent condition persists for more than 7 clock

cycles of the converter, a fault condition is declared

and the converter shuts down and goes into either a

hiccup restart mode or latches off. The behavior can

be selected through the PMBus interface. Other

PMBus interface features include programmable

operating frequency, soft-start time, overvoltage and

undervoltage thresholds and the response to those

events, output voltage change including margining as

well as status monitoring.