TPS5430X

Part: TPS5430, TPS5431 — Texas Instruments

Type: Synchronous Buck Converter

Description: The TPS543x is a high-output-current PWM converter that integrates a low-resistance, high-side N-channel MOSFET, offering up to 3-A continuous output current, adjustable down to 1.22 V with 1.5% initial accuracy, and a fixed 500 kHz switching frequency.

Operating Conditions:

• Supply voltage: 5.5–36 V (TPS5430), 5.5–23 V (TPS5431)
• Operating temperature: -40 to 125 °C
• Switching frequency: 500 kHz (typical)

Absolute Maximum Ratings:

• Max supply voltage: 40 V (TPS5430), 25 V (TPS5431)
• Max junction temperature: 150 °C
• Max storage temperature: 150 °C

Key Specs:

• Quiescent current (not switching): 3 mA (typ)
• Shutdown current: 18 μA (typ)
• Voltage reference accuracy (TJ = 25°C): 1.221 V (typ), 1.202 V (min), 1.239 V (max)
• Internally set free-running frequency: 500 kHz (typ), 400 kHz (min), 600 kHz (max)
• Current limit: 5 A (typ), 4 A (min), 6 A (max)
• Thermal shutdown trip point: 162 °C (typ), 135 °C (min)
• High-side power MOSFET switch rDS(on): 110 mΩ (typ), 230 mΩ (max)

Features:

• Up to 3-A Continuous (4-A Peak) Output Current
• High Efficiency up to 95%
• Adjustable Output Voltage Down to 1.22 V with 1.5% Initial Accuracy
• Internal Compensation Minimizes External Parts Count
• Fixed 500 kHz Switching Frequency
• Improved Line Regulation and Transient Response by Input Voltage Feed Forward
• Overcurrent Limiting, Overvoltage Protection and Thermal Shutdown
• -40°C to 125°C Operating Junction Temperature Range

Applications:

• Consumer: Set-top Box, DVD, LCD Displays
• Industrial and Car Audio Power Supplies
• Battery Chargers, High Power LED Supply
• 12-V/24-V Distributed Power Systems

Package:

• 8-Pin SO PowerPAD™ Package (HSOP)

• 1 · Wide Input Voltage Range:

• Up to 3-A Continuous (4-A Peak) Output Current

• High Efficiency up to 95% Enabled by 110 m Ω Integrated MOSFET Switch

• Wide Output Voltage Range: Adjustable Down to 1.22 V with 1.5% Initial Accuracy

• Internal Compensation Minimizes External Parts Count

• Fixed 500 kHz Switching Frequency for Small Filter Size

• Improved Line Regulation and Transient Response by Input Voltage Feed Forward

• System Protected by Overcurrent Limiting, Overvoltage Protection and Thermal Shutdown

• -40°C to 125°C Operating Junction Temperature Range

• Available in Small Thermally Enhanced 8-Pin SO PowerPAD™ Package

• TPS5430: 5.5 V to 36 V

• TPS5431: 5.5 V to 23 V

• Consumer: Set-top Box, DVD, LCD Displays
• Industrial and Car Audio Power Supplies
• Battery Chargers, High Power LED Supply
• 12-V/24-V Distributed Power Systems

TJ = -40°C to 125°C, VIN = 12 V (unless otherwise noted)

over operating free-air temperature range (unless otherwise noted) (1)(2)

• (4) Test boards conditions:

1. (a) 3 in x 3 in, 2 layers, thickness: 0.062 inch.
2. (b) 2 oz. copper traces located on the top and bottom of the PCB.
3. (c) 6 thermal vias in the PowerPAD area under the device package.

• (5) Test board conditions:

1. (a) 3 in x 3 in, 4 layers, thickness: 0.062 inch.
2. (b) 2 oz. copper traces located on the top and bottom of the PCB.
3. (c) 2 oz. copper ground planes on the 2 internal layers.
4. (d) 6 thermal vias in the PowerPAD area under the device package.

The TPS543x is a 3-A, step down regulator with an integrated high side MOSFET. This device is typically used to convert a higher DC voltage to a lower DC voltage with a maximum available output current of 3 A. Example applications are: High Density Point-of-Load Regulators for Set-top Box, DVD, LCD and Plasma Displays, High Power LED Supply, Car Audio, Battery Chargers, and other 12-V and 24-V Distributed Power Systems. Use the following design procedure to select component values for the TPS543x. This procedure illustrates the design of a high frequency switching regulator. Alternatively, use the WEBENCH software to generate a complete design. The WEBENCH software uses an iterative design procedure and accesses a comprehensive database of components when generating a design.

To begin the design process a few parameters must be decided upon. The designer needs to know the following:

• Input voltage range
• Output voltage
• Input ripple voltage
• Output ripple voltage
• Output current rating
• Operating frequency