Texas Instruments TPS40003 manual Compensation Design

Page 8

SLUU130A – September 2002 – Revised February 2003

4.7Compensation Design

The TPS40003 uses voltage mode control in conjunction with a high frequency error amplifier. For the fastest transient response, the loop crossover frequency is set at 1/10 fS, or 60 kHz. The power circuit L-C double pole corner frequency fC is situated at 24 kHz, and the output capacitor ESR zero is far higher at approximately 1MHz. The feedback compensation network is implemented to provide two zeroes and three poles. The first pole is placed at the origin to improve dc regulation.

The first zero is placed at approximately 2/3 fC, 18 kHz,

fz1

+

 

 

 

1

 

 

 

 

 

 

 

 

(6)

 

 

p

R2

C4

 

 

 

 

 

2

 

 

 

 

 

The second zero is selected at fC,

 

fz2

+

 

 

 

 

1

 

 

 

 

 

 

 

(7)

2 p

￿R4 ) R5￿

C12

 

 

 

The two poles are placed at approximately 300 kHz, which is one-half the switching frequency,

 

fp1 +

 

 

 

1

 

 

 

 

 

 

 

 

 

 

 

C4

C8

(8)

 

 

 

 

 

 

 

 

2 p R2 ￿

 

 

￿

 

 

 

C4)C8

 

and

 

 

 

 

 

 

 

 

 

 

 

 

 

 

fp2

+

 

 

 

1

 

 

 

 

 

 

 

 

(9)

 

 

p

R5

C12

 

 

 

 

 

2

 

 

 

 

 

8TPS40003-Based 5-A Converter in Less Than One Square Inch

Page 7 Page 9
Image 8
Page 7 Page 9
Contents User’s Guide EVM Important Notice Dynamic Warnings and Restrictions Features IntroductionSchematic Application Diagram for the TPS40002/3Design Procedure TPS4000X Family Device SelectionInductance Value Input Capacitor SelectionShort Circuit Protection Output Capacitor SelectionMosfet Selection Compensation Design Snubber Component Selection PowerPAD Packaging PowerPAD PCB Layout GuidelinesTest setup is shown in figure Test Results/Performance DataTypical Switch Node Waveform Efficiency Output CurrentShort Circuit Operation Output Voltage RippleStartup Waveform Transient ResponsePCB Layout List of Material Reference Qty Description Manufacturer Part NumberImportant Notice

TPS40003 specifications

The Texas Instruments TPS40003 is a versatile, high-performance synchronous buck controller designed to efficiently regulate output voltage in a range of applications. This device is particularly suited for power supply designs where space and efficiency are critical, such as telecommunications, industrial automation, and consumer electronics.

One of the standout features of the TPS40003 is its ability to operate over a wide input voltage range of 4.5V to 36V. This flexibility allows it to be effectively utilized in various scenarios, accommodating different power supply systems and ensuring compatibility with existing infrastructure. Furthermore, the output voltage can be adjusted down to as low as 0.8V, making it suitable for powering low-voltage microcontrollers and FPGAs.

The TPS40003 incorporates advanced voltage mode control, which enhances transient response and stability. This control method allows for quick adjustments in duty cycle in response to load changes, ensuring a steady output voltage even under varying loads. Coupled with a programmable soft-start feature, the controller minimizes inrush current during startup, protecting sensitive downstream components.

Another significant advantage of the TPS40003 is its integration of a high-side and low-side MOSFET driver. This synchronous operation significantly improves power efficiency by reducing conduction losses. The device operates with a high switching frequency, typically around 200 kHz, allowing for the use of smaller passive components and ultimately leading to a more compact design.

Thermal performance is another essential characteristic of the TPS40003. With built-in thermal shutdown and overcurrent protection features, it promotes reliable operation under various thermal conditions, enhancing the overall robustness of the power supply design. Additionally, the device's wide range of compensation options allows designers to fine-tune performance according to specific application requirements.

In terms of packaging, the TPS40003 is offered in a compact, thermally enhanced HTQFN package, which helps in conserving PCB space while maintaining efficient heat dissipation.

Overall, the Texas Instruments TPS40003 controller stands out as a robust, feature-rich solution for DC-DC conversion applications. With its wide operating voltage range, synchronous operation, and protective features, it provides designers with a reliable, efficient means of managing power in today's demanding electronic systems.
Top Page Image Contents